Saltwater crocodiles used to occupy a massive range that stretched across the Indian Ocean to the Seychelles, new DNA research confirms.

The now-extinct population of crocodiles in the Seychelles, an archipelago in the western Indian Ocean, was not a group of Nile crocodiles (Crocodylus niloticus), nor was it a separate species. Instead, it was likely the westernmost population of saltwater crocodiles (Crocodylus porosus), which today live in India, Southeast Asia, Australia and islands across the Western Pacific, researchers reported Jan. 28 in the journal Royal Society Open Science.

"The founders of the Seychelles population must have drifted at least 3,000 kilometers [1,864 miles] across the Indian Ocean to reach the remote archipelago, perhaps even much further," study co-author Frank Glaw, a reptile expert at the Bavarian State Collections of Natural History, said in a statement.

The Seychelles used to be home to a large population of crocodiles, according to expedition notes from more than 250 years ago. But when human settlers arrived in the late 18th century, they wiped out all of the crocodiles on the islands. The remains of a few specimens were kept in museums in the Seychelles, London and Paris.

Initially, Western scientists thought the Seychelles crocodiles were part of a population of Nile crocodiles that had migrated from Africa. But in 1994, researchers reclassified the preserved remains as saltwater crocodiles based on their physical traits.

In the new study, a different team of scientists confirmed that conclusion using genetic material. They collected mitochondrial DNA from the skulls and teeth of several older museum specimens of various crocodile species and then compared that DNA with tissue samples from modern museum specimens and living crocodiles.

The genetic markers of the Seychelles crocodiles matched closely with those of the saltwater crocodiles, the team found. That suggests that saltwater crocodiles' range stretched over 7,500 miles (12,000 km) from east to west before the Seychelles population was exterminated.

"The genetic patterns suggest that saltwater crocodile populations remained connected over long periods and across great distances, pointing to the high mobility of this species," study co-author Stefanie Agne, an evolutionary biologist at the University of Potsdam in Germany, said in the statement.

To spread as far west as the Seychelles, C. porosus would have had to cross thousands of miles of ocean. But the crocodiles are adapted to life at sea, sporting special salt glands on their tongues that let them expel excess salt. That adaptation could have helped the animals spread widely across the Indo-Pacific region and limited further speciation, the researchers wrote in the study.

But future work could still uncover differences among groups of saltwater crocodiles. Mitochondrial DNA is inherited only from the mother, and it might not capture subtle genetic differences driven by male crocodiles. Future studies using DNA from the nuclei of crocodile cells could help unpack any regional differences among populations, the researchers wrote.

Researchers have identified two new crocodile species living on isolated islands in the Caribbean — and they're both threatened with extinction, a new study has found.

The reptiles, previously thought to be American crocodiles (Crocodylus acutus), separately inhabit the island of Cozumel and the atoll of Banco Chinchorro off Mexico's Yucatán Peninsula. Both populations have around 500 individuals.

Scientists identified the as-of-yet unnamed species while studying the genetics of crocodiles across Mexico's Pacific coast, Central America and the Caribbean. The team found stark genetic differences between the Cozumel and Banco Chinchorro populations and the rest of the American crocodile species, concluding that the island crocodiles were separate species, according to a statement released by McGill University in Canada.

"These results were totally unexpected," study lead author José Avila-Cervantes, who carried out the genetics research during his graduate studies at McGill University, said in the statement. "We assumed Crocodylus acutus was a single species ranging from Baja California to Venezuela and across the Caribbean."

The researchers' findings will appear in the upcoming June volume of the journal Molecular Phylogenetics and Evolution — they were first published online on March 28.

Related: Crocodiles are overheating due to climate change — and it's changing their behavior

American crocodiles live across 18 countries, ranging from the southern tip of Florida to the Caribbean and northern South America. They share some of that range with Cuban crocodiles (C. rhombifer) in Cuba and Morelet's crocodiles (C. moreletii) in Mexico, Guatemala and Belize.

The researchers were studying variation across all three species when they identified the two new species on Cozumel and Banco Chinchorro. Their work involved capturing and releasing crocodiles to extract blood and tissue samples for DNA analysis. The team also used genetic data from previous studies and compared physical differences between the crocodiles, according to the study.

The main physical difference between the different species is that their skulls vary in length and shape. For example, the Banco Chinchorro crocodiles have a longer and broader snout compared to those of Cozumel Island, according to the study.

The discovery of two new species could be important from a conservation perspective. Crocodiles in the region are already under threat from human activities including urbanization, pollution and tourism. The researchers found the populations on Cozumel and Banco Chinchorro appear to be stable, but that they are vulnerable due to their small size and restricted habitat, according to the statement.

"Now that we recognize these crocodiles as distinct species, it’s crucial to protect their habitats," Hans Larsson, a biology professor at McGill University and the study's principal investigator, said in the statement. "Limiting land development and implementing careful conservation strategies on Cozumel and Banco Chinchorro will be key to ensuring their survival."

Crocodile quiz: Test your knowledge on the prehistoric predators

Climate change may be pushing crocodiles to their limit, a new study finds.

In Australia, estuarine crocodiles (Crocodylus porosus) are struggling due to global warming. Like most reptiles, crocodiles are ectothermic (cold-blooded), which means their body temperatures are determined by the external environment rather than by internal processes — in contrast to endothermic (warm-blooded) animals, such as birds and mammals.

When crocodiles need to warm up, they lie in the sun. And when they need to cool down, they may lie in the shade, retreat to cool streams and pools, or bask on the shore at night.

But a warming climate has increased these crocs' body temperatures, which in turn appears to be changing their behavior. In a paper published Feb. 12 in the journal Current Biology, scientists report that over a 15-year period, the average body temperature of the crocodiles increased by a small but significant amount. Further, they spent more days at their critical thermal limit — 89.6 degrees Fahrenheit (32 degrees Celsius).

Previous research on captive crocodiles has shown that body temperatures of 89.6 F or higher lead to reduced swimming and diving performance. When their bodies get too hot, crocodiles spend more time attempting to cool themselves and reduce their activity.

"A hotter croc has a higher metabolism," lead author Kaitlin Barham, a doctoral candidate studying crocodile movement and behavior at the University of Queensland, Australia, told Live Science. "Higher metabolism means burning oxygen more rapidly. Lab research found that they just couldn't hold their breath for as long. It would take them a bit longer to recover at the surface."

Related: Why can't you suffocate by holding your breath?

Between 2008 and 2023, the researchers studied 203 estuarine crocodiles (also called saltwater crocodiles) at the Steve Irwin Wildlife Reserve in Queensland. They tracked the reptiles' body temperatures using acoustic devices implanted under the skin. These devices sent signals to nearby receivers and additional trackers were used to monitor when the crocodiles submerged themselves, and for how long.

If a crocodile was not detected for a period ranging from 30 minutes to 24 hours and then was detected again with a higher or lower body temperature, the scientists assumed that the croc had altered its behavior to regulate its body temperature — either basking in the sun to raise it or finding a cool spot to lower it.

"The croc would disappear for a few hours, and then come back 1 or 2 degrees [C, or 1.8 to 3.6 F] cooler," Barham said.

During the study period, the researchers recorded nearly 6.5 million temperature readings from the crocodiles. The highest body temperatures increased by 0.99 F (0.55 C). Of the crocodiles that were monitored, 135 showed body temperatures exceeding 89.6 F at least once, and one individual showed body temperatures above 89.6 F for more than a month in 2021.

The highest body temperatures were linked to El Niño periods, during which unusually warm Pacific currents led to hot, dry spells on land. The frequency of these periods is believed to be increasing as a result of climate change.

Cooling behaviors were detected more frequently when ambient temperatures were hotter. The crocodiles also submerged themselves for shorter periods when temperatures were high, according to the tracking data.

It is unclear how these alterations to the crocodiles' behavior are affecting their survival. They are certainly adapted to high temperatures already, but it is possible that increasing periods of hot weather may reduce their ability to hunt. Crocodiles are stealth predators and usually submerge themselves to ambush prey on the shores of rivers.

"Every minute that they're up on the bank trying to bring their body temperature down is a minute that they're not spending traveling, reproducing or looking for food," Barham said. "That could result in future indirect effects on their health."

Crocodile quiz: Test your knowledge on the prehistoric predators

Name: Cave-dwelling dwarf crocodiles (Osteolaemus tetraspis)

Where it lives: Abanda cave system, Ogooue-Maritime Province, Gabon

What it eats: Cave crickets and bats

Why it's awesome: Deep inside one of Gabon's cave systems lives an unusual population of orange dwarf crocodiles. They live in complete darkness, feast on bats and swim in liquid guano (aka bat poop.)

It's unknown how many crocodiles are living in these caves, or when they adopted this subterranean lifestyle, but they may have been down there for thousands of years — and scientists say they may even be in the process of evolving into a new species.

The cave-dwelling crocodiles were only studied for the first time in 2010, and a 2016 study that compared them to their forest-dwelling counterparts showed a number of differences between the two. Their diets are very different, with the cave crocs feeding almost exclusively on the bounty of crickets and bats that cling to the cave walls. They found the cave crocodiles were generally in better condition than those living in the forest, which the team say is likely due to the abundance of prey available and a lack of predators.

They suggest the cave crocodiles lay their eggs at the mouth of the caves, then the juveniles venture into the darkness. Once they reach adulthood, it's thought they barely leave the caves again.

Orange skin and genetic changes

The unusual orange skin seen on adult crocodiles may be the result of their time swimming in bat guano, which is rich in urea, lead author Matthew Shirley, a conservation biologist from Florida International University, told National Geographic in 2018. Over time, this exposure appears to cause chemical bleaching of the crocodiles' skin, the study authors wrote.

Intriguingly, genetic analysis of the crocodiles — which has not been published — suggests the orange cave crocodiles may be mutating, according to a Guardian article in 2018. Researchers told the newspaper that one haplotype (a group of DNA variants inherited from a parent) found in the cave crocs wasn't present in the forest crocodiles. "The [crocodiles in the] caves of Abanda stand out as an isolated genetic group," study co-author Richard Oslisly, a researcher at France's Institute of Research for Development, told the Guardian.

This genetic change is evidence that the cave crocodiles are evolving into a new species. "As a result of that isolation and the fact that few individuals come in or go out, they're in the process of [becoming] a new species," Shirley told National Geographic. "Whether that happens soon or not is anyone's guess."

Crocodile quiz

Henry the world's oldest known crocodile is celebrating his 124^th birthday at a conservation center in South Africa today (Dec. 16).

The Nile crocodile (Crocodylus niloticus) has lived at the Crocworld Conservation Centre in Scottburgh, South Africa since 1985. He was originally captured in the Okavango Delta in Botswana in 1903.

Henry, now a vigorous senior resident at the Crocworld Conservation Center, is said to have fathered over 10,000 offspring with numerous partners since he arrived there almost 40 years ago.

While his exact birthday is unknown, Crocworld representatives estimate he was born around 1900 and celebrate his birthday on Dec. 16 each year.

"He's clearly old," Steven Austad, a biologist studying animal aging at the University of Alabama, told Live Science. "Whether he's 100 or 130, we don't really know. An age of 124 is not inconceivable for a crocodile."

Reptiles are known for their impressive longevity. Usually, a good rule of thumb for an animal's lifespan is to look at their size — smaller animals typically live shorter lives because they have higher metabolisms, meaning that they burn more energy and age more rapidly as a result.

But even compared with other animals of roughly the same size, reptiles tend to be much longer-lived. Austad said that being cold-blooded allows them to conserve energy by relying on external heat sources to regulate their body temperature.

"A crocodile that was the same size as a person would only need to eat about 4% as much as a mammal like us," he said.

Crocodiles, like some other reptile species, continue growing with age. Henry weighs 1,540 pounds (700 kilograms) and measures 16.4 feet (5 metres), which is on the larger end for his kind. Their huge size keeps them safe from potential predators in their old age.

Related: Scientists to read Cassius the giant crocodile's bones to find out exactly how old he was when he died

Henry's life in captivity has also likely helped him reach such an old age, keeping him well fed and safe from accidents and disease.

"Animals that for whatever reason, happen to live in a safe environment, tend to live longer," Austad said.

Reptiles, compared to many other vertebrates, also do not show signs of noticeable decline in physiological abilities as they age.

Other biological traits may also contribute to Henry's longevity. Theories posit that proteins found in the blood of Nile crocodiles may have antibacterial properties and help them fight off infections and disease. Similarly, some researchers claim that their gut microbiomes could contribute to their robust immune system.

Studying the aging of crocodiles like Henry can be challenging since researchers have to catch them in their infancy, tag them, then follow them throughout their lives. Because of this, many theories around the secrets to reptilian aging are speculative, like the role of their immune system and microbiome, Austad said. "[Crocodiles] live longer than the careers of the scientist studying them," he said.

Name: Gharial (Gavialis gangeticus)

Where it lives: Freshwater rivers in India and Nepal

What it eats: Fish. Juveniles also eat insects, frogs and crustaceans.

Why it's awesome: The gharial is known for its long, skinny snout, which looks like it got slammed in a door.

An adult male has a "ghara" at the end of its snout: a lightbulb-shaped bump, named after a bulbous Indian pot. This bizarre lump looks attractive to females and helps males woo their mates by blowing bubbles and creating a strange love song.

This ghara "partially covers the crocodile's nostrils and acts as a vocal resonator, creating a loud, buzzing sound when the gharial vocalizes," according to Smithsonian’s National Zoo and Conservation Biology Institute.

If these crocodilian pickup lines are successful and the male attracts a female — or several, as gharials are polygamous — the pair mate. This usually happens in December or January. In March or April, when the dry season arrives, females dig nests and lay around 40 eggs.

Related: Low-flying helicopter sparks massive crocodile orgy in Australia

These large eggs are the biggest of all crocodilian eggs. Weighing up to 6 ounces (170 grams), they're about the same weight as a hockey puck. Once fully grown, adults can reach 15 feet (4.5 meters) and, on average, weigh around 350 pounds (160 kilograms).

"As with all crocodilians, the sex of the hatchlings is determined during incubation," according to Smithsonian. Incubation can take between 60 and 80 days. Babies stay with their mother for several weeks, or sometimes months, after hatching.

Although they look like crocodiles or alligators, gharials split off from other crocodilian species over 40 million years ago.

Unlike crocs and gators, gharials don't ambush their prey. Instead, swiping their snout from left to right allows them to detect vibrations in the water. Using this method, they find nearby fish and chomp on them with their interlocking teeth.

These animals are well-adapted to watery habitats but can’t move well on land because their leg muscles are too weak, so they slide on their bellies to get around above water.

Gharials were once plentiful between Pakistan and Myanmar, with an estimated 5,000 to 10,000 individuals in the wild in the 1940s. They are now critically endangered as a result of hunting, fishing and habitat loss, with around 650 mature individuals left. Captive breeding, nest monitoring and other conservation activities helped boost this number from around 250 in 2006.

Crocodiles are among the world's most impressive, deadly predators. They are masters of camouflage, waiting patiently for unsuspecting prey to approach before lunging at high speeds. They have thick, rigid skin and dozens of sharp teeth inside jaws that deliver some of the biggest bite forces of any living animal. Other than humans, adult crocs have no natural predators.

They've existed for millions of years, now inhabiting five of Earth's seven continents.

But how much do you know about crocodiles? Take our science quiz to find out.

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Scientists in Australia may soon learn exactly how old the giant crocodile Cassius was when he died after performing a necropsy on the record-breaking predator.

Cassius, who was the world's largest living captive crocodile, died in Australia this month after 40 years in captivity. Experts estimated the gigantic saltwater croc (Crocodylus porosus) could have been over 120 years old — but they don't know for sure.

Sally Isberg, founder of the Centre for Crocodile Research in Australia’s Northern Territory, told ABC News that "all indications at this stage indicate that he has died of [old age]."

But further tests following the animal autopsy, which will be carried out imminently, may also reveal the 17 feet and 11.75 inch (5.5 meters) croc's exact age, something that even his keepers — who made up his birthday — had never been sure of.

When Cassius was captured in the Finniss River, near Darwin, in 1984, researchers believed he may have been up to 80 years old. But once crocodiles fully mature, their growth rates slow down, making it impossible to determine his exact age.

"There is no way of knowing Cassius' actual age as he was born in the wild and the age is just an estimate," Toody Scott, one of Cassius' keepers at Marineland Crocodile Park, previously told Live Science.

Related: World's largest captive croc turns 120, giving scientists 'serious knowledge on longevity'

The only way to find out the animal's age involves cutting into its bones to count the growth rings, which can only be done after death. Scientists plan to cut into Cassius' back and right femur bone to take samples that will be sent away for testing.

"My plan is to send it to a lab that can cross-section it and look for growth rings, just like in trees," Isberg told ABC News. However, it could take months before the results are back and the process isn't guaranteed to work, she added. "I'm a little bit concerned that those growth rings might not be quite as easily discernible."

Grahame Webb, a zoologist and leading crocodile researcher, helped capture Cassius from the wild in 1984 after the aggressive croc started attacking cattle and boat propellers. He told ABC News that counting growth rings might not give an accurate age estimate. "These animals stop growing and they can live for decades afterwards without growing," he said.

Cassius measured just under 18 feet (5.5 m) long when he died. However, he was also missing part of his snout and the end of his tail. Without these battle scars, Webb believes the crocodile would have reached a total length of 19 feet (5.8 m).

Cassius, the world's largest captive crocodile, has died in Australia after his health started declining in mid-October.

"It is with deep sadness that we share the passing of our beloved mate Cassius," Marineland Melanesia Crocodile Habitat & Gift Shop wrote in a Facebook post announcing his death. "He was more than just a Crocodile, he was a cherished member of our family and brought joy and companionship to his best mate George for over 37 years."

The saltwater crocodile (Crocodylus porosus) — who was 17 feet and 11.75 inches (5.48 meters) long — received the Guinness World Record as the largest living captive crocodile in 2011. But, as no one measured him since, he could have grown even bigger. The species can grow up to 23 ft (7 m) long.

Cassius had lived at Marineland Melanesia Crocodile Habitat on Australia's Green Island since 1987. He was captured in the Finniss River, near Darwin, in 1984 because he was acting aggressively and causing problems.

"As an apex predator, this big crocodile was getting into all sorts of trouble, from catching and eating cattle to attacking boat propellers," Marineland Melanesia's representatives wrote on its website. "It is believed this is where and how he sustained his many battle scars, including losing his front left leg, part of his snout and around 15 cm [6 in] off the end of his tail."

Related: The longest-living animals on Earth

Cassius was moved to an "assisted care residence" in Cairns on Oct. 5 and his health started declining shortly after. He died on Nov. 2. "He was very old and believed to be living beyond the years of a wild croc," according to Marineland Melanesia's post.

Although experts aren't sure, they think this massive croc may have been over 120 years old when he died. When he was caught, Cassius was estimated to be between 30 and 80 years old. Crocodile growth rates slow significantly once they reach adulthood.

"There is no way of knowing Cassius' actual age as he was born in the wild and the age is just an estimate," Toody Scott, one of Cassius' keepers at Marineland Crocodile Park, previously told Live Science, adding that his birthday "was essentially made up."

Despite his enormous size, Cassius wasn't the largest crocodile ever kept in captivity. This record goes to a saltwater crocodile named Lolong, who was caught in the Philippines in September 2011, and measured over 20 ft (6.17 m) before his death in 2013.

Australia has a crocodile problem. In the last two decades, attacks have risen sharply after the population exploded. Along with safety messaging, government officials are increasing the number of permitted crocodile kills, but experts say the move isn't likely to work given how mobile crocodiles are — kill one, and another will immediately move into its territory.

But a new, stealthy way of preventing attacks may be on the horizon. The tool involves using the genetic fingerprints of crocodiles to identify areas where these predators are present. By harnessing environmental DNA (eDNA), wildlife officials could test waterways and warn swimmers, boaters and campers to avoid areas where crocodiles are, or have recently been.

The croc problem is partly the result of one of conservation's greatest success stories. In the early 20th century, thanks to overhunting, the Australian crocodile population plummeted to around 3,000. After protections were introduced in the 1970s, the population surged, and now an estimated 100,000 live in waterways across the country.

Because of this rise, both crocodile attacks and retaliatory attacks by humans are increasing. In the latest incident, on Aug. 3, 40-year-old David Hogbin fell into the Annan River in Queensland and was killed by a 16-foot-long (5 meters) saltwater crocodile (Crocodylus porosus), which was later killed by wildlife officials. And in 2023, a 13-foot (4 m) crocodile was found beheaded on a beach. A few months later, a 40-year-old female croc was also found dead, having been butchered with just her head and spine remaining.

Related: 'Eyes coming straight for me': Huge crocodile launches itself into boat with jaws wide open in strange attack

One reason it's hard for people to avoid croc attacks is that they are some of the world's ultimate ambush predators. They can sit completely still underwater for up to eight hours, waiting for unsuspecting prey to pass by before they strike. From the surface, the water may seem croc-free, but people should "assume crocodiles are present in all waterways," according to advice from the Northern Territory Government.

So researchers are developing tests that will show where crocodiles are — without ever needing to see them.

"Environmental DNA (eDNA) relies on detecting trace amounts of DNA that all living organisms leave behind … things like hair, skin cells, feces or urine," Elise Furlan, a molecular ecologist with the University of Canberra (UC) who works on the program, told Live Science in an email.

To test for eDNA, the team collects water samples and filters them. The scientists then extract any detectable DNA in the lab, amplifying it and searching for evidence of croc DNA, Furlan said.

To check the test's accuracy, the team searched for eDNA in water from crocodile-holding ponds at a Queensland Department of Environment, Science and Innovation (DESI) facility and compared the results with those from water that never housed crocodiles. After the crocodiles were removed from the pond, they tested the water to establish how quickly the DNA degrades, according to a statement from the DESI. This should reveal how long a crocodile needs to be in a body of water for it to be picked up by the tests, and how long after it has left the area its traces remain.

The program is in its early stages. Right now, samples need to be analyzed in the lab, but the researchers hope that as the work progresses, they can develop a spot-test to detect crocodiles in real time, Furlan said. The tests are not 100% accurate and there's a risk of false negative detection, but it's still likely to be better than traditional detection methods, Furlan said..

The hope is eDNA tests could be used in conjunction with other attack-prevention tools, such as public safety messaging.

In future work, the team plans to sample rivers and other water bodies in Queensland where crocodiles are present to establish the tests are effective in real-world environments.

"This research absolutely has the potential to have a very practical application," Furlan said.

In this adapted extract from "Bite: An Incisive History of Teeth, from Hagfish to Humans" (Algonquin Books, 2024), author and vertebrates zoologist Bill Schutt investigates the extraordinary bite force of living crocodilians, as well as their formidable predecessors, Deinosuchus and Sarcosuchus — the "most forceful biters in history."

"There are no 'pretty good' crocodilian researchers, Gregory Erickson quipped. “In my business, if you're not very good, you're missing an arm or something." Erickson, a professor of anatomy and vertebrate paleobiology at Florida State University, also emphasized that it takes a team of experienced handlers to secure the larger specimens. "We always have four or five people who really know their stuff."

Though Erickson has a range of research interests, I’d contacted him because of his research into the biting behavior of alligators, crocodiles and their relatives,

Once strapped down, a tap on the snout usually causes the test subject to open its mouth, after which the bite bar is placed onto the rear teeth. That's because the laws of physics dictate that a measurement taken closest to the jaw joint will provide the greatest bite force.

This placement also stimulates something akin to the knee-jerk reaction you might have experienced while being examined by a rubber-mallet-wielding physician. Here, though, the reflexive response by the crocodilian is to chomp down on the bite bar with full force. Although Erickson's first experiments centered on alligators (which makes perfect sense, given his Florida location), eventually he and his coworkers were able to obtain bite-force data on all 23 species of extant crocodilians, a group that includes crocodiles, alligators, caimans (alligator relatives from Central and South America), and gharials (narrow-snouted piscivores).

"We try to do three to five [individuals] of each species," Erickson said, emphasizing that this practice increased the chances of obtaining a true indication of the bite forces for that species. Ultimately, the largest animals they measured were several 17-foot (5.2 meters) saltwater crocodiles (Crocodylus porosus), which, along with the Nile crocodile (Crocodylus niloticus), happen to be the species involved in the greatest number of fatal and nonfatal attacks on humans.

Erickson and his fellow researchers were interested in determining how bite forces varied between species. Before their study, there had been several hypotheses predicting that bite forces in crocodilians would vary depending on factors like tooth shape, or the length or width of the jaw — variables that were readily observable traits commonly used to identify the species in question.

In something of a surprise, though, Erickson and his colleagues found that bite force was solely dependent on body size. "We got the same regression lines pound for pound," he told me. In other words, if you had a crocodile, alligator and caiman, each weighing 100 pounds (45 kilograms), their bite forces would be the same.

All the smaller species had smaller bite forces. The 17-foot saltwater crocodiles generated a bite force of 3,700 pounds (1,680 kg), but when those numbers were scaled up to the historically recorded 23-footers (7 m), Erickson said, "7,700 pounds [3,500 kg] is not infeasible."

There were, however, two exceptions to the size/bite force correlation: the two species of gharials (Gavialis gangeticus and Tomistoma schlegelii), whose long, skinny snouts look oddly out of place attached to a body that can reach 12 to 15 feet (3.7 to 4.7 m) in length or more and weigh in at up to 2,000 pounds (900 kg).

Their extremely elongated jaws are equipped with 110 interlocking, needle-like teeth, and the whole setup is wonderfully well adapted for slashing through the water with little resistance. But their bite force is significantly below expected values for critters of that size. Erickson believes the gharials' specialized fishing tackle is the cause, and that it resulted in an evolutionary trade-off in which greater bite force was sacrificed for the sake of rapid fish-snatching ability, made possible by an extremely long set of toothy jaws.

Unfortunately, the two living species of gharials are critically endangered. Within the gharials' riverine habitats on the northern Indian subcontinent, their numbers may have fallen to levels measured in the hundreds of individuals. Except for the narrow-nozzled gharials, all crocodilians, no matter their size, come equipped with some seriously powerful jaws.

Erickson hypothesizes that this adaptation evolved in ancestral crocodilians during the age of dinosaurs, enabling them to carve out an ecological niche along the water's edge that they've successfully held for over 100 million years. He compared crocodilian diversity to starting out with a big, powerful engine, then tweaking the attachments you could add to that megaforce-generating machine — tweaks that would include variation in the length, width and shape of the "stuff out in front of the eyes" (Erickson's term for the jaws and teeth). These attachments helped the different crocodilians become better adapted to prey on a variety of creatures, from mollusks to fish, and from birds to big game.

When considering the bite of a crocodilian, Erickson stressed the fact that just as important as the total force a crocodilian jaw might produce is the surface area where that force is being applied — in other words, the force per unit area, or pressure. That's because this measurement not only factors in the forces generated but also the shape of the tooth.

Erickson compared a pointy tooth like a crocodile canine to a shoe with a stiletto heel, which he described as more capable of damaging a wooden floor than a shoe with a flat sole. The force applied to the ground by the high-heel wearer is distributed across a smaller unit of area (the tip of the high heel) than it would be across the broad, flat sole of a sneaker. In pointy canine teeth, the bite force is distributed over a small surface area at the tooth tip, making them effective for piercing a prey's skin or hide.

Conversely, flat teeth, like premolars and molars, distribute bite forces over a greater surface area, making them ideal for turning large chunks of food into smaller chunks.

Of course, I was interested in the greatest bite force ever generated by an animal, extinct or extant, so I asked Erickson. He told me that was a tough question (presumably in part due to the scarcity of researchers during the age of dinosaurs) but that data points to a pair of prehistoric apex predators.

The first is Deinosuchus, a now-extinct crocodilian relative of modern alligators. Deinosuchus lived around 82 million to 75 million years ago in what is now the United States, where it reached lengths of almost 33 feet (10 m). "I don't think that any animal that has ever lived could have broken the grip of Deinosuchus," Erickson told me.

"So, what about escaping the grasp of an adult American alligator (Alligator mississippiensis) nowadays?" I wondered. "How hard would that be?"

"The bite force of a very large alligator is about 3,000 pounds [1,360 kg], about the weight of a small car," Erickson said. "So if you can bench press a car, you are good to go … If not, you're lunch."

The second contestant in the Greatest Bite Force of All Time Contest is Sarcosuchus. With a body length of about 40 feet (12 m), this behemoth lived in what is now South America and Africa 133 million to 112 million years ago. Sarcosuchus is classified as a crocodyliform (a "crocodile-like" creature). This means that although it certainly had the look of a card-carrying crocodilian, Sarcosuchus is not believed to be an ancestor of modern crocodiles and their relatives.

Still, Erickson believes that, like Deinosuchus, Sarcosuchus was generating a bite force of 20,000 pounds (9,000 kg), a number that his team estimated by scaling up the data from extant crocodilians. "I think they were right up there with the most forceful biters in history," he told me.

There are apparently limits, though, on the amount of bite force that can be generated. These relate to how much stress can be placed on the enamel covering of a tooth before it shatters. But, Erickson reminded me, this type of creature has a safeguard against that potential disaster. "Crocodilians all break their teeth," he said. "But they have one advantage over mammals — they can replace their teeth throughout their lives."

From "Bite: An Incisive History of Teeth, from Hagfish to Humans" by Bill Schutt. Used with permission of the publisher, Algonquin Books. Copyright © 2024 by Bill Schutt. This excerpt has been edited for space and clarity.

Alligators in North Carolina and Texas are surviving a cold snap by suspending their bodies in pond water and letting it freeze solid around them, videos show. Only their snouts and front teeth poke through the ice, allowing the alligators to breathe while they wait for the water to thaw.

"People keep asking how the swamp puppies are doing — I'm happy to report that they are frozen solid," a representative of the Swamp Park in southern North Carolina, said in a video on Facebook. "We literally have 'gatorcicles' right now."

Several alligators were found frozen inside giant ice cubes at the Swamp Park, a tourist attraction and alligator sanctuary near Ocean Isle Beach, North Carolina. Another alligator was spotted suspended in an icy pond at the Gator Country rescue center in Beaumont, Texas.

Both states have experienced dips in temperature below 30 degrees Fahrenheit (minus 1 degrees Celsius) in the past week, with a cold snap of 17 degrees Fahrenheit (minus 8 degrees Celsius) recorded in North Carolina.

A TikTok video taken at Gator Country this weekend shows an alligator lying motionless in a murky pond with its snout sticking out from below the icy surface. "He has pushed his snout up through the yuck to breathe," Gary Saurage, the owner of the rescue center, said in the video.

Alligators survive frigid temperatures by entering a state of torpor called brumation — the cold-blooded, reptilian equivalent to hibernation in mammals.

Related: Pinky-white leucistic alligator with blue eyes born in Florida is 1 of only 8 in the world 

When it gets so cold that water freezes, alligators "instinctively tilt their nose up" so it sticks out of the water to stop them suffocating, the Swamp Park representative said in the video.

When ice crystals start to form, alligators' metabolism slows down and their lethargic bodies gradually become suspended in the frozen water with their eyes closed. Unlike mammals that hibernate, alligators and other reptiles don't fall into a deep sleep during brumation and still have periods of activity, so they can drink.

During brumation, an alligator's heart can slow down to as few as three beats per minute, Saurage said in the Tiktok video. "Folks, that's amazing," he added. "That's how alligators survive in the ice."

A fisher experienced the shock of a lifetime when a large crocodile launched itself onto his boat with its jaws wide open in Australia.

The incident occurred at Jane Creek — a stream northeast of Mackay in Queensland — on the morning of Dec. 31, 2023. The man was identified by ABC News as 45-year-old Richard Brookman, a local who has fished at this creek for decades. He had been on the water for around four hours when, at 10 a.m. local time, he spotted a crocodile swimming toward his small aluminum boat, or tinnie. 

Brookman told ABC he had an "eerie feeling" of being watched: "I turned the headlight on and had to look up the creek and there's these eyes coming straight for me," he said. Brookman estimated the crocodile was around 13 feet (4 meters) long, while his boat was 10 feet (3 m) long, according to ABC. 

The fisher moved to the back of the tinnie to start the engine, but the crocodile suddenly leapt into the air and crashed onto the boat.

"The crocodile [swam] under the tinnie, then turned and launched itself up and into the vessel with its jaws wide open," Jane Burns, a senior wildlife officer with the Queensland Department of Environment, Science and Innovation (DESI), said in a statement. "The man then jumped the crocodile to get to the bow of the tinnie and retrieve the anchor, and the crocodile pivoted, over-balanced and fell back into the water, bending the rails of the tinnie."

Related: Watch rare footage of huge crocodile eating baby hippo with umbilical cord still attached

The crocodile was only in the tinnie for a few moments, and the fisher returned safely to shore, according to the statement. "This would have been a frightening incident," Burns said.

Speaking to wildlife officers on Monday (Jan. 1), the fisher said he had never seen such a large crocodile behaving this way in the region before. Burns also told ABC this was an unusual incident. "To launch themselves at a boat near a boat or at a person, it's not what we would call typical [crocodile] behavior," she said. "It is concerning behavior, so it is definitely getting investigated and we'll look further into this animal's behavior."

She added that crocodiles jumping onto boats is normally accidental and often occurs when they are trying to get back into the water. 

The DESI said in the statement it will conduct daytime surveys to find the crocodile and install warning signs until the animal is located. "Should we not confirm the presence of a crocodile during our daytime search, we will conduct a nighttime spotlight assessment in Jane Creek," Burns said. "If a crocodile is in the vicinity, we will assess its behavior and the risks posed to public safety."

If wildlife officers locate the croc and believe it poses a threat, they will remove the animal from the wild, Burns added. Brookman told ABC News he would like to see the crocodile relocated.

Crocodile attacks in Queensland are rare, although officials warn there is a risk in waterways where they are present. Between December 1985 and July 2023, there were 47 reported attacks in the state, 13 of which were fatal.

In June 2023, a man narrowly escaped from the jaws of a saltwater crocodile (Crocodylus porosus) that attacked him from behind while he was snorkeling off the coast of Queensland. 

An exceptionally rare light-pink alligator has been born at Gatorland, a wildlife park in Orlando, Florida.

The female American alligator (Alligator mississippiensis) has a genetic condition known as leucism, which results from a mutation in the genes that leads to reduced pigment in feathers, hair or skin. Unlike albinism, which results in  pink eyes and a complete loss of skin pigment, animals with leucism only have a partial loss of pigment and normally have blue eyes and white, translucent or pale pink skin. 

The newly born reptile is believed to be one of only eight leucistic alligators in the world. They are very occasionally born in the wild, but rarely survive beyond infancy due to health problems.

Because leucistic alligators lack normal skin pigmentation and thus sunburn easily, they cannot be exposed to sunlight for long periods and are at higher risk of sun damage and skin cancer. Leucistic alligators are also rarely seen as adults because their skin means they are easily spotted by predators.

However, the baby alligator is in good health and currently measures 19.2 inches (49 centimeters) long and weighs 3.3 ounces (96 grams), park representatives said.

Related: Extremely rare white killer whale spotted off California coast 

It was born to a mother who did not have leucism but carried the genetic mutation for the condition and a leucistic father. (Because leucism is a recessive condition, two copies of the genetic variant — one from the mother and one from the father — are needed for the condition to result in observable traits.) The leucistic alligator was born alongside a non-leucistic male, who is the same size.

Footage shared by Gatorland showed the pink leucistic alligator freshly emerged from its shell.

The color of leucistic alligators may change over time because, unlike albino animals, they still have the genes for pigmentation.

A study published in 2020 detailed the extraordinary finding of six leucistic American alligator hatchlings in South Carolina in 2014. The animals were underweight when they were found, and three died shortly after being collected. The remaining three alligators lived in captivity for several years until their deaths.

"They weren’t going to survive," lead author Thomas Rainwater, a research scientist at Clemson University in South Carolina, said in a statement released at the time. "They were all fairly emaciated, often have congenital health defects, and are easily detected by predators. 

"Rather than letting nature take its course in this case, or having the hatchlings possibly poached by reptile traders, we collected the alligators in an attempt to nurse them to better health and potentially capitalize on their value in wildlife education and conservation," he added.

Paleontologists in Spain have unearthed a 4.5 million-year-old tooth that likely belonged to one of the last crocodiles in Europe.

The tooth is the only crocodilian fossil excavated from a site called Baza-1 in the southern province of Granada and indicates the predator looked similar to Nile crocodiles (Crocodylus niloticus) that live in Africa today.

Baza-1 was first excavated in the early 2000s and has yielded more than 2,000 fossils, despite only covering an area of 323 square feet (30 square meters), according to a translated statement. 

"The tooth we found at the site of Baza-1 corresponds to a true crocodile," said Bienvenido Martínez Navarro, a paleontologist with the Catalan Institution for Research and Advanced Studies (ICREA) and research professor at the Catalan Institute of Human Paleoecology and Social Evolution (IPHES) who co-led the recent excavations. "We have classified it as Crocodylus because, at the moment, the only evidence of its presence at this site is this tooth, and we don't have enough anatomical resolution to be more precise," Martínez Navarro told Live Science in an email.

Related: 'They mated like mad': Low-flying helicopter sparks massive crocodile orgy in Australia

This is the most recent evidence of a crocodile ever found in the fossil record in Europe, Martínez Navarro said. Until now, fossils suggesting crocodiles roamed the continent came from earlier deposits, including from the Miocene (23 million to 5.3 million years ago) and from very early on during the Pliocene (5.3 million to 2.6 million years ago).

Crocodiles likely crossed over from Africa to Europe around 6.2 million years ago, just before the Mediterranean Sea dried up during what is known as the Messinian salinity crisis, Martínez Navarro said.

The Messinian salinity crisis was partly triggered by a global cooling event that locked ocean water up in glaciers and icebergs, lowering sea levels by about 230 feet (70 meters), according to the University of Maryland. This drop resulted in less water flowing from the Atlantic Ocean into the Mediterranean. Meanwhile, tectonic shifts also caused the ocean floor around the Strait of Gibraltar to rise, isolating the Mediterranean, which ultimately became disconnected from the world's oceans and dried up.

This left behind a vast expanse of salt up to 2 miles (3 kilometers) thick in some places, which scientists found buried beneath hundreds of feet of sediment in the 1970s.

"It was possible to walk from northern Africa to the Iberian Peninsula," Martínez Navarro said, adding that several species would have crossed this expanse.

The Messinian salinity crisis lasted roughly 700,000 years and ended abruptly when a gigantic surge of water known as the Zanclean flood — triggered by evaporated water returning to the oceans and erosion of the strip of land around Gibraltar — replenished the Mediterranean Sea.

African crocodiles that found their way to modern-day Spain and Portugal likely disappeared when the climate became colder and drier during the Pliocene, Martínez Navarro said. The early Pliocene, however, was characterized by a tropical climate that supported a rich assemblage of animals — including now-extinct elephants, reptiles, amphibians and fish — whose remains were also unearthed at the site where the tooth was found.

Researchers hope the fossils unearthed at Baza-1 will help them reconstruct a critical moment in paleohistory, when species migrated from Africa to Europe, Martínez Navarro said.

Rare footage has captured the moment before a huge crocodile began feasting on a newborn hippo in Kenya's Maasai Mara. The hippo appeared to still have its umbilical cord attached as the crocodile held its body in its jaws and thrashed the carcass around. 

Frankie Adamson, a wildlife photographer who was working as the resident photographer for the safari operator Governors' Camp Collection, filmed the incident from the banks of the Mara River. 

"It's generally accepted that crocodiles would not approach or threaten an adult hippo, but I have heard that they are opportunists and if it's possible they would take a chance to snatch a baby," Adamson told Live Science in an email. "It is something I had never seen with my own eyes, however."

Adamson was alerted to the crocodile with the hippo calf by a colleague. 

Related: Indian crocodiles seen saving dog from feral pack attack, but scientists divided over what it means

"The crocodile already had the baby hippo held in its jaws by the time I approached, and I was fairly certain it was already dead," she said. "This raised questions in my mind as to whether the crocodile had killed it, or whether it had been still-born and the carcass snatched as I later saw the baby's umbilical cord still attached."

Adamson said there were no other hippos in this section of the river. The crocodile was initially still in the water, holding the carcass in its jaws, but it began throwing the corpse around when it was disturbed by catfish. "It started lifting the carcass up out of the water and very violently thrashing it around," Adamson added.

Crocodiles thrash their heads from side to side to kill prey or to break it into smaller chunks. Adamson said she watched the crocodile with the hippo for around 45 minutes but did not see it eat any of the carcass. Eventually it swam away with its meal downriver. 

Nile crocodiles (Crocodylus niloticus) grow up to around 16 feet (5 meters) long and are aggressive and opportunistic apex predators. They generally feed on fish but will also target terrestrial mammals like zebras, impalas and buffalos. But adult hippopotamuses (Hippopotamus amphibius) can grow to 16.5 feet (5 m) long and weigh up to 9,920 pounds (4,500 kilograms) and could easily kill a crocodile. Crocs sometimes prey upon hippo calves, but then run the risk of being attacked by the mother hippo. 

"It's certainly not often that these ruthless and most efficient apex predators snatch baby hippos from their mothers — in fact as opportunistic as crocodiles are — they will often avoid hippos as they know just how aggressive an angry hippo can be," Governors Camp Collection wrote in an Instagram post. 

A large-scale saltwater crocodile mating frenzy was recently triggered by an unlikely suspect in Australia — a low-flying Chinook helicopter. Ranchers from the Koorana Crocodile Farm in Queensland, which is home to over 3,000 crocodiles, said their scaly residents became aroused after the flyby and "mated like mad." 

John Lever, owner of the farm, told ABC that the Chinook pilots use his farm as a marker point to change course mid-flight, with one pilot recently coming especially low so the people on board could snap a few photos of the crocs.

"All of the big males got up and roared and bellowed up at the sky, and then after the helicopters left they mated like mad," Lever said. "There's something about the sonic waves that really gets them stirred up." 

So what is it about low-flying helicopters that gets crocs in the mood? Herpetologist Mark O'Shea from the University of Wolverhampton in the U.K., told Live Science there are a few reasons why a helicopter might spark a crocodile sex frenzy.

Related: World's largest captive croc turns 120, giving scientists 'serious knowledge on longevity'

One reason may be tied to helicopters simulating many of the warning signs of an incoming thunderstorm.

Heavy rains are known to have an aphrodisiac effect on many species of crocodilians. And saltwater crocodiles (Crocodylus porosus) appear to time mating so new hatchlings do not drown in flood water after heavy rains and storms, O'shea said. They mate during thunderstorms so offspring are more likely to hatch in more moderate conditions.

"Usually, mating is a seasonal thing because [crocodiles] want to coincide with the best time to lay their eggs in a burrow or nest," O'Shea said.

Warm and wet weather usually triggers mating behaviors, and October is just about the right time for crocodile romance in Northern Australia, where Lever's crocodile farm is located.

But the low-flying helicopters' rotors may produce the same signals that tell crocodiles a storm is close.

Crocodiles have multi-sensory organs called integumentary sensory organs (ISOs) that are used to detect changes, such as movements in the water, atmospheric pressure and sounds at extremely low frequencies.

"I imagine that the downdraft from a large, heavy helicopter would create a change in pressure that the ISOs on crocodile skin can detect," O'Shea said. "Dropping barometric pressure from a downdraft may resemble the change in pressure from a storm.

Another potential explanation, O’Shea says, is that the Chinooks could be producing infrasound – sounds so low in frequency that they are undetectable to the human ear. Such vibrations can also be picked up by ISOs.

“Chinooks may artificially recreate the sound of the start of a thunderstorm,” he said.

Such vibrations play an important function in crocodilian communication, O'Shea said. The sound of a Chinook's powerful rotors may resemble the sound of competing crocodilian males, such as the low bellowing sounds of males looking for a mate, or the sound of males slapping the water with their jaws — another territorial and courting behavior.

So, is a Chinook helicopter all it takes to get crocodiles in the mood? O'Shea says he is not so sure. Crocodiles may need to already be picking up subtle cues, like changes in temperature, that signal their traditional mating season is about to start in order to be swayed by the large aircraft.

Editor's note: The original image on this article was of American alligators (Alligator mississippiensis). The image has been updated to show a saltwater crocodile. 

Scientists in India have observed mugger crocodiles engaging in some strange behaviors, including hunting in packs, using sticks as bait to lure herons and egrets within striking range, showing interest in flower garlands floating in the river and even saving a feral dog that had been chased by other dogs. 

The new study, published Aug. 26 in the Journal of Threatened Taxa, suggests that mugger crocodiles (Crocodylus palustris) inhabiting the Savitri River in Maharashtra, India are more cognitively advanced than scientists currently believe. 

As tantalizing as these observations are, though, an expert Live Science contacted is skeptical, noting that while the hunting behaviors have previously been reported — anecdotally — the latter two claims are almost certainly anthropomorphic conjecture. 

"Crocodilians do have a sophisticated suite of behaviors," said Duncan Leitch, a biologist specializing in the neurophysiology of reptiles at the University of California, Los Angeles, who was not involved in the research. "But some of these conclusions are using a human definition of intelligence and trying to find that in crocodilians."

Related: Crocodiles and gharials are getting bizarre orange 'tans' in Nepal. Here's why.

The new study recorded several instances in which groups of mugger crocodiles swam in circles around schools of fish, creating a vortex. Their movement was presumed to have corralled the fish, and the crocodiles were observed consuming them while engaging in this behavior. Similar behaviors have previously been observed in other crocodilians. 

The recent paper said mugger crocodiles appear to use sticks to lure wading birds such as cattle egrets (Bubulcus ibis). These birds use sticks in constructing their nests, and competition for prime twigs can be intense. So, a branch positioned on a crocodile snout might seem a tempting option.

A 2013 paper also chronicled a series of anecdotal observations of crocodilians using sticks to entice wading birds. 

"Crocodilian sensory systems are incredibly sophisticated. They have a very good sense of vision. Their sense of touch is among the finest in the animal kingdom," Leitch said. "They're definitely tuned to picking up signals from their environment. Whether or not this is intelligence in the way that we see crows using tools — it's difficult to say."

He added that the anecdotal evidence cited is not widely accepted among crocodile researchers. 

The authors also said that mugger crocodiles appear to be attracted to  garlands of marigold (Tagetes erecta) flowers dropped into the river during funeral rites. The researchers suggested the crocodiles may be enticed by both the color of the flowers and their antibacterial properties. 

However, the crocodiles were not observed interacting with or consuming the flowers — they were simply found in proximity to them. Though the authors cited incidents in which captive crocodilians were observed playing with bougainvillea flowers, no such behavior was observed in the muggers. 

Crocodile empathy?

The researchers also reported an incident in which a young dog was chased into the river by a pack of adult feral dogs. Rather than eating the dog, three mugger crocodiles seemed to nudge it back to shore. 

"[The crocodiles] guided the dog away from the site where it would have been vulnerable to being attacked by the pack of feral dogs waiting on the river bank," they wrote. "These crocodiles were actually touching the dog with their snout and nudging it to move further for a safe ascent on the bank and eventually escape."

The authors interpreted this action as empathic — suggesting the crocodiles may have been concerned for the dog's safety. While it is certainly interesting that they did not consume an obvious prey item, there is little evidence that crocodilians are capable of empathy for other species, Leitch said.  

"They [the authors] may be coming from an anthropomorphic perspective and trying to ascribe abilities that they potentially might not have," Leitch said.

Anecdotal findings like the ones offered in this paper may offer prospects for additional investigation. But in the absence of more rigorous research they are just that: anecdotal, Leitch said.

A huge alligator weighing almost 1,000 pounds (455 kilograms) has been caught in Florida — the second heaviest in state history. The supersized reptile, which was likely between 60 and 90 years old, measured over 13 feet long (4 meters) when hunters hauled it in on Aug. 26. 

U.S. Coast Guard Capt. Kevin Brotz, a hunting guide from Florida Gator Hunting and Get Bit Outdoors, was with friends on a lake near Orlando when they noticed a huge alligator (Alligator mississippiensis) swimming away from them, he told Field and Stream. They spent around four hours battling with the alligator, and at one point it leapt 3 to 4 feet (0.9 to 1.2 m) out of the water. "It looked like a blue whale when it breached," Brotz told the site. 

Related: 120-year-old Cassius is pushing limit of crocodile longevity — and he's got 'years to come,' expert says

After pulling the alligator on board, they killed it and took it to shore where it was weighed and measured. It came in at 920 pounds (417 kg) and 13.06 feet. That makes it the second heaviest ever caught in Florida. The heaviest weighed 1,043 pounds (473 kg) and was caught in 1989. 

Brotz told Live Science in an email that catching alligators of this size is extremely rare. "I've guided hundreds — if not close to a thousand gator hunts — and this one is absolutely in a league of its own."

Florida is home to an estimated 1.3 million gators. This one was killed as part of Florida's statewide alligator harvest program, which has run since 1998 and helps to keep the population in check. 

The hunting season generally runs between August and November. Around 7,000 permits are issued each year, with the Florida Fish and Wildlife Conservation Commission issuing tags that authorize holders to kill two alligators. In 2022, 7,804 alligators were killed as part of the program. 

Brotz's catch follows the capture of an 802-pound (364 kg) alligator that was 14 feet and 3 inches (4.34 meters) long — the longest ever caught in Mississippi. This alligator was killed during Mississippi's 10-day alligator hunting season.

Hunters have killed the longest alligator ever captured in Mississippi in the state's Yazoo River.

The record-breaking animal measured 14 feet and 3 inches (4.34 meters) long and weighed in at 802.5 pounds (364 kilograms), according to the Mississippi Department of Wildlife, Fisheries and Parks (MDWFP). The previous record for the "longest male alligator taken by a permitted hunter in Mississippi" belonged to a 14-foot, 0.75-inch-long (4.29 m) animal weighing 766.5 pounds (347.5 kg) that hunters captured in 2017 near the western city of Natchez.

Hunters caught the new record-size male on Saturday (Aug. 26) during Mississippi's 10-day alligator hunting season, which kicks off on the last Friday of August each year, according to the MDWFP.

"It was a calm night," Donald Woods, who participated in the hunt, told Clarion Ledger, a Jackson, Mississippi news outlet. "We saw a lot of 8-footers, 10-footers, but that's not what we were after."

Related: Human remains found inside 500-pound alligator. How common are alligator attacks?

The hunters spotted the humongous alligator and got a hook on it around 9 p.m. local time, Woods said, but it took the team seven hours to subdue and kill the beast. "We hooked him eight or nine times and he kept breaking off," Woods said. "It was more mentally exhausting than anything because he kept getting off."

Only after hoisting the alligator onto their boat did the hunters realize how gigantic it was. "We were just amazed at how wide his back was and how big the head was," Woods said. "It was surreal, to tell you the truth."

The team notified MDWFP Alligator Program coordinator Andrew Arnett, who officially measured and weighed the animal before announcing the new record. The hunters posed with their catch at Red Antler Processing, a wild game processing facility in Yazoo City.

Alligators (Alligator mississippiensis) are native to the southeastern U.S. and found all across Mississippi. It is illegal to hunt and capture alligators outside of the hunting season and without a special permit from the MDWFP. Permit holders may catch two alligators over 4 feet long (1.2 m) and one over 7 feet long (2.1 m), so as to distribute the hunting pressure across adult and juvenile animals.

The biggest American alligator ever recorded was a 15-foot, 9-inch giant caught in Alabama in 2014 that weighed 1,011.5 pounds (459 kg). Alligators' growth rates slow as they get older and depend on the animal's sex, age and habitat. Male alligators usually grow faster and larger than females, but they rarely exceed 13 feet (4 m) in length. 

Cassius, the largest living crocodile in captivity, could be even bigger than previously thought.

The saltwater crocodile — who is thought to be 120 years old — entered the record books in 2011, when he measured nearly 18 feet (5.48 meters) long. But his keepers haven't measured him since, meaning Cassius may have grown even bigger since then.

"It's very possible Cassius may have grown bigger since 2011, however we have not attempted to remeasure him," Toody Scott, who looks after Cassius at Marineland Crocodile Park in Australia, told Guinness World Records. "We may attempt this in the near future to provide some insight into growth rates of large crocodiles or of course if his record was being challenged."

Saltwater crocodiles (Crocodylus porosus) can grow up to 23 feet (7 m) long, with another record holder — a 50-year-old, captive animal in the Philippines named Lolong — measuring more than 20 feet (6.17 m). Lolong was captured in 2012 and briefly replaced Cassius as record-holder, but the crocodile died one year later after flipping over with a bloated stomach and Cassius was reinstated as the world's largest captive croc.

Related: Crocodiles are drawn to the wails of crying human babies and infant primates

Despite having likely lived more than twice as long, Cassius probably won't catch up with his predecessor. "As crocodiles get larger than 5 m [16.4 feet], growth rates seem to slow to as little as 1 cm [0.4 inch a year] and in many instances the crocodile may stop growing," Scott said.

But Cassius might also be missing a few inches as a result of injuries he sustained in the wild. When researchers captured him in 1984, the gigantic croc had been fighting other crocodiles over territory and attacking boat engines, resulting in him losing bits of his snout and tail. These missing body parts were not factored into his 2011 measurements and could have added an extra 6 to 10 inches (15 to 25 cm) to his length, according to Guinness World Records.

Based on the size of crocodiles that have lived in the Marineland park since birth, Cassius' keepers estimate the colossal croc was born in 1903. This year therefore marks the saltwater giant's 120th birthday, and his keepers say Cassius may have "years to come."

"Becoming a Guinness World Record holder certainly shot Cassius to 'croc-stardom,'" Scott said.

Nile crocodiles respond to the sound of human babies crying, as well as the cries of infant chimpanzees and bonobos, a new study finds.

What's more, the crocodiles seemed to be most responsive to higher-intensity cries — and may even be better at picking up on the level of distress in those cries than humans are.

It's unclear from the study whether this behavior was motivated by the crocodiles trying to hunt vulnerable prey or for some other reason, like confusing these infants' cries with the cries of juvenile crocodiles, for example, which can sound like squeaking or cooing. But these results give researchers more insight into how these reptilian giants perceive the world.

Researchers played cries from human, chimpanzee and bonobo infants to a group of Nile crocodiles (Crocodylus niloticus) at a zoo, recording how many of the crocodiles turned their heads or moved toward the speaker in response to the sounds. They published their results Aug. 8 in the journal Proceedings of the Royal Society B.

The crocodiles responded to cries from human, bonobo and chimp infants. But not all crying sounded the same. 

Related: How are alligators and crocodiles different?

The researchers used sound recordings of human babies from two contexts: during bathtime at home with their parents, which resulted in a low-intensity crying, and vaccination at the doctor's office, which resulted in higher-intensity crying.

Some of the more intense baby cries caused a much higher percentage of the crocodiles to respond. To see if there were specific qualities of those sounds that made the crocodiles perk up, the researchers also analyzed some of the acoustic properties of the cries they tested.

They found that the crocs were more responsive to crying sounds with more energy in higher sound frequencies, as well as crying sounds with some irregularities in the sound wave patterns, both of which are associated with higher levels of distress, the authors noted.

Think about a crying baby who’s really upset — the sound of that crying is irregular and all over the place as the baby is screaming and losing their breath, Miriam Boucher, a doctoral candidate at Clemson University who was not involved in the new research, told Live Science.

Humans tend to rank higher-pitched calls as more distressed, but that doesn't always lead to an accurate assessment, the study authors noted. For example, because bonobo cries are generally higher-pitched than those of humans, people tend to overestimate how distressed the bonobo cries are, the authors said. Crocodiles, on the other hand, did not seem to respond all that differently to cries of different pitches.

"Crocodiles thus seem particularly adapted at estimating the degree of distress encoded in an infant's cry regardless of the hominid species considered," the authors noted.

It's possible that these animals picked up on distress as a cue to spot a potential meal nearby, and the researchers noted that some of the crocodiles responded to the calls by swimming underwater, which could be a predatory maneuver. Swimming underwater could also just mean that the animals were being cautious as they investigated the sound, Boucher said.

And the crocodiles could also have been responding to these cries for some reason other than predation. The study didn't compare the crocodiles' response to these cries to another kind of sound, such as the distress cry of a juvenile crocodile or a neutral sound. Kent Vliet, a retired biologist formerly at the University of Florida who was not involved in the new research, told Live Science that he’s seen crocodilians (a group of animals that includes crocodiles, alligators and caimans) respond intensely to juvenile distress calls, even when they were coming from other crocodilian species.

In addition, these animals might simply have been curious about a new sound nearby.

"What I've seen in my own work," Boucher said, "is crocodilians can be pretty curious about things in general."

Cassius, a 120-year-old crocodile living in captivity in Australia, is "happy and healthy" and will live "for years to come," experts who conducted his annual health check say.

"Cassius is such a magnificent, beautiful boy," Sally Isberg, managing director at the Center for Crocodile Research in Australia who led the assessment, said in a video shared with Live Science. "He's just an absolutely fascinating character."

At 18 feet (5.5 meters) long, Cassius is the world's largest crocodile living in captivity and recently turned 120, or thereabouts. A health assessment conducted June 19 found "no reason to believe Cassius will not live for years to come," Toody Scott, a crocodile keeper at the Marineland park where Cassius now lives, told Live Science in an email.

Researchers don't know how long saltwater crocodiles (Crocodylus porosus) can live for, but they can die of old age, said Adam Rosenblatt, an assistant professor of biology at the University of North Florida.

"My own educated guess is that the maximum lifespan for crocodilians as a group is in the range of 100-120, but they would only attain those ages in captivity," Robenblatt told Live Science in an email. "In the wild most crocodilians probably don't live past 60."

Related: 'Virgin birth' recorded in crocodile for 1st time ever

Cassius has spent more than 35 years at the Marineland Crocodile Park on Green Island. He was captured on a cattle ranch in 1984 after he attacked livestock, having roamed in the wild for up to 80 years. 

The researchers noted that the gigantic croc becomes skittish when keepers use machinery around the park, which may stem from trauma he suffered during his time in the wild.

Keepers told Isberg that Cassius "exhibits funny behavior" and "reacts badly" when they use loud equipment and machinery near his enclosure.

"He was taken from a situation in the wild where I feel that he wasn't very happy," Isberg said.

Cassius was missing the tip of his snout when he was caught, leading researchers to believe he was responsible for attacks on boats that — at the time — were pinned on another crocodile called Sweetheart. 

"He had the tip of his snout broken, which you can get from attacking a propeller," Grahame Webb, a crocodile researcher who participated in the capture, told ABC News.

Crocodiles have extremely sensitive mouths, and Cassius may be more delicate than most. 

"The scales on the front of their mouth are all about pressure receptors; they're all about honing in on prey," Isberg said. "Maybe those boat motors [created] extra vibration that quite irritated him. When a croc gets irritated by something, the only way he can express that irritation is to go to bite at it," Isberg said.

But now, in captivity, Cassius appears to be "a happy, healthy boy," Isberg said.

The ancient crocodile will undergo another checkup next year. Assessments are typically done through observation to avoid causing the animal stress. "Crocs are apex predators and have a very heightened fight or flight response," Scott said. "If restrained, the flight response is triggered and it can take some time for the crocodile to recover."

In the meantime, keepers will make sure Cassius gets enough sunlight to stay healthy by clearing the tree canopy over his pen.

"A stress-free crocodile generally will self-heal any injuries and be free from disease, as they have a stronger immune system [than stressed crocodiles]," Scott said.

Cassius, the world's largest crocodile living in captivity, just turned 120 years old. Or at least that's his estimated age, scientists say. 

It's difficult to determine a crocodile's age based on its size. Once they reach adulthood, the rate at which crocodiles grow slows down and eventually grinds to a halt. The largest crocodiles are usually the ones that grow in irregular spurts as juveniles, with males typically growing bigger than females.

"There is no way of knowing Cassius' actual age as he was born in the wild and the age is just an estimate," Toody Scott, a crocodile keeper who looks after Cassius at Marineland Crocodile Park on Green Island, told Live Science in an email. The nearly 18-foot-long (5.5 meters) saltwater giant's birthday "was essentially made up a few years ago" and this time of year is actually "the wrong time of year for a crocodile to be born in northern Australia," Scott added.

In 1984, researchers captured the crocodile on a cattle ranch southwest of Darwin, Australia, after the ranch owners complained they were losing livestock. Even then, when Cassius was estimated to be between 30 and 80 years old, he was the biggest crocodile ever caught alive in Australia.

"He was 16 feet, 10 inches [5.13 m] with at least another 6 inches [15 centimeters] of tail missing and a bit of a snout missing," Grahame Webb, a crocodile researcher who participated in the capture, told ABC News. "He was a big old gnarly crocodile then. Crocs of that size are not normal."

Related: Crocodile murder mystery deepens following discovery of 2nd corpse with 'fileted' head

Nearly 40 years later, and after 35 years living on Green Island, the colossal crocodile is still growing, "which is unusual for a big croc" and is providing scientists with "serious knowledge on longevity," Webb said.

Cassius was a difficult catch for Webb and his colleagues back in the 1980s. Large crocodiles had been prime targets for hunters, so researchers rarely had the opportunity to study them. "Adult crocodiles that survived the hunting period were very wary," Webb said. (Australia's Northern Territory banned crocodile hunting in 1971.) 

Now, Cassius is anything but wary, according to his keepers. "He still has a lot of spark in him" and is "always up for an interaction," Scott told ABC News. While other old reptiles tend to be docile and uninterested, "he's one of the liveliest crocs and very engaging."

Saltwater crocodiles (Crocodylus porosus) typically live for more than 70 years, according to the nonprofit conservation organization Oceana. The largest saltwater crocodile ever captured was Lolong, a 20.3-foot-long (6.17 m) beast from the Philippines.

A massive "salty" crocodile was captured in Australia in 2018, but the 15.4-foot-long (4.7 m) animal was nowhere near the size of Cassius, who has been holding onto the Guinness World Record for the largest captive crocodile since 2011. 

Trouble is brewing in Australia's "Croc Country" after a female crocodile was found "fileted," with only her head and spine left behind.

Local tour guides spotted the butchered carcass on May 18 on the banks of the Daintree River, Queensland. The death marks the second mysterious crocodile killing in recent months, following the discovery of a gigantic male with its head torn off on a beach in Cow Bay. 

The latest crocodile corpse was found 5 miles from the site of the beheaded crocodile. 

A local wildlife tour guide told Live Science he received an anonymous phone call from a person claiming they killed both crocodiles to prove that humans are the apex predator. "He knew exactly where her body was left, the exact position, and also said he fileted her up but didn’t want her head as he had the bigger head already," David White, the operator of Solar Whisper Daintree River Crocodile and Wildlife Cruises, said in an email.

The Queensland Department for Environment and Science (DES) said experts were unable to determine the recently killed crocodile's cause of death. Crocodiles in Queensland are a vulnerable species and are protected by law. "It is unlawful to deliberately harm or kill crocodiles or be in possession of a deceased crocodile or parts of a deceased crocodile," a DES spokesperson told Live Science in an email.

When the Daintree River guides first saw the latest carcass, they thought that a male crocodile vying for territory had slaughtered the female. But upon closer inspection, they became doubtful. "Some other guides that saw her remains and some experienced croc people asked for the photos and thought it was strange," White said.

Related: Man survives crocodile attack by prying its jaws off his head. How did he escape such a powerful bite?

White said he last saw the crocodile — a nearly 9-foot-long (2.7 meters) female he had named "Lizzie" — alive on May 11. Her head and spine were found a week later, dumped beside his boat on a riverbank that neither she nor other crocodiles were known to frequent.

White noted it was surprising that Lizzie was missing for a week before the carcass was found, as crocodile carcasses tend to float on the water’s surface or wash up soon after the animal has died. "This river is used a great deal and there was no bloated body."

The clean-picked remains also raised eyebrows. "The state of her body was strange, she was just an intact spine and a face and nothing else," White said. It didn't look as if another crocodile had attacked Lizzie, because they "break off bits by twisting, turning and smashing the prey, so we think that if she was killed by a croc, the head would have been damaged and the spine eaten," White added.

Then came the phone call from someone claiming to have slaughtered both Lizzie and the crocodile in Cow Bay. White said the caller knew details about where Lizzie's remains were found that he had not made publicly available. The caller claimed to have "fileted her like a fish and fed her to his dogs," White said.

Removing a large, mature crocodile from an ecosystem can cause an imbalance in the local croc society. When the headless Cow Bay crocodile was found, Cameron Baker, a postdoctoral researcher at Charles Darwin University in Australia, told Live Science: "It will likely represent a period of social unrest and change in the population as individuals try to determine where they sit in the new social hierarchy resulting from this large male's loss." 

The loss of a female has different implications. Lizzie was a roughly 40-year-old breeding female — "the best mom of any croc on the river," White said. "She once had some runts that never grew and she remained with the creche for seven months instead of the 1-3 months average. She also adopted a baby in a year she didn’t nest and sat with it every day."

The removal of a mature, breeding female from the ecosystem could mean that younger females start nesting sooner, according to a 1989 IUCN report.

White said the other crocodiles on the river seem unsettled of late, but he added this could be due to an ongoing power struggle between two males, including one they initially thought had killed Lizzie. "I am of course worried about all the other crocs on the river," he added. "They are habituated to ignore us, so every one of them is a sitting duck." 

Scientists have announced the first ever recorded case of a crocodile "virgin birth" after a female that had been isolated for 16 years was discovered with a clutch of eggs. The discovery provides "tantalizing insights" into the evolutionary origins of the trait, potentially shedding light on the reproductive capabilities of dinosaurs, a new study finds. 

The American crocodile (Crocodylus acutus) was taken into captivity in 2002 when she was 2 years old and placed in an enclosure at Parque Reptilandia in Costa Rica. She remained alone for the next 16 years. But in January 2018, a clutch of 14 eggs was found in the enclosure. 

Virgin births, also known as facultative parthenogenesis (FP), is a type of asexual reproduction in species that would normally reproduce sexually. Scientists have documented it in birds, sharks, lizards and snakes in captivity, among other species. Until now, it had never been recorded among Crocodilia — the order that includes crocodiles, alligators, caimans and gharials. 

Related: Mystery of what, or who, butchered Australian crocodile deepens following discovery of 2nd corpse

In a study published on Wednesday (June 7) in the journal Biology Letters, researchers said seven of the 14 eggs produced by the crocodile in Costa Rica were viable. Zoo caretakers incubated these eggs, but they didn't hatch, so after three months, they opened the eggs. The contents of six of the eggs was "not discernable," but one contained a fully-formed, but non-viable fetus. Genetic analysis showed it was almost identical to the mother. 

The team, led by Warren Booth, an entomologist at Virginia Tech, wrote in the study that it was "disappointing" the egg failed to hatch, but that it is not unusual for offspring born this way to suffer abnormalities and fail to thrive. FP, they added, may be more common in species on the brink of extinction, and studies investigating wild populations could reveal more cases. 

They also said the discovery of a virgin birth in a crocodile means FP has now been found in both birds, which descended from dinosaurs, and a crocodilian, suggesting a common evolutionary origin. Birds and crocodilians are the remaining representatives of archosaurs — the group that also included dinosaurs and pterosaurs. 

"This new evidence offers tantalizing insights into the possible reproductive capabilities of extinct archosaurian relatives of crocodilians, notably the Pterosauria and Dinosauria," they wrote. 

A man in Australia recently escaped from the reptilian jaws of death after a crocodile clamped down on his head. 

Marcus McGowan was snorkeling about 25 miles (40 kilometers) from the Cape York coast in Queensland when a saltwater crocodile (Crocodylus porosus) attacked him from behind. These reptiles have the strongest measured bite force of any animal on Earth. But McGowan pried open the reptile's jaws before it could snap down even harder. 

"I was able to lever its jaws open just far enough to get my head out," McGowan said in a statement released by the Cairns and Hinterland Hospital and Health Service. "The crocodile then attempted to attack me a second time, but I managed to push it away with my right hand, which was then bitten by the croc."

He was then taken to hospital and treated for scalp lacerations and puncture wounds on his head and hand — relatively minor injuries considering he went head to head with one of the planet's most powerful predators. 

Related: How are alligators and crocodiles different?

Powerful bite

Crocodiles are well known for their vice-like jaws. "It might look like they have really fat necks, but actually that's extra jaw muscle," Paul Gignac, an anatomical researcher at the University of Arizona, told Live Science. 

This gargantuan neck muscle — known as the ventral pterygoideus muscle — enables adult saltwater crocodiles to clamp down on their prey with a force of 3,700 pounds per square inch (16,460 newtons), according to a 2012 study co-authored by Gignac. In comparison, jaguars (Panthera onca) can bite down with a force of around 1,500 psi. 

McGowan believes the crocodile that attacked him was about 6.5 to 10 feet (2 to 3 meters) long, which suggests it was a juvenile. However, even young crocodiles can pack a serious punch, generating around 250 psi (1,112 newtons) of bite force at the back of their jaws, Gignac said. 

"It is generally surprising [McGowan survived]," Gignac said. Crocodiles are "not known to let go once they hold on."

Gignac noted that "this man's probably especially lucky that the juvenile was either too small or didn't have a positioning to start rolling," a behavior known as a "death roll," in which crocodiles violently twist in the water while holding their prey to disorient or dismember it. "Otherwise, it might be the case that this person would have lost a limb." 

Staring death in the face

So how exactly did McGowan escape the crocodile's vice-like grip? There could be a few factors at play. For one, the crocodile may not have been able to wrap its entire jaw around McGowan. 

"The bite force gets lower as you go out away from the jaw joint," Gignac said. "So the tip of their snout will typically have about 40% lower bite force, and that's just due to the engineering or the physics behind the way levers work."

The croc's stamina may also have played a part. Reptiles are cold blooded, or ectothermic, meaning they largely rely on external heat sources to manage their body temperatures and have slower metabolisms than warm blooded, or endothermic animals. As a result, they typically have smaller reserves of energy than most endothermic animals. So even though a crocodile's attack may be vicious at first, "they do become tired relatively quickly," Gignac said, adding that crocodiles need rest before reaching peak performance again.

Under these conditions, then, it may be possible for a human to dislodge themselves from a crocodile's mouth. When attacked, humans often release massive amounts of adrenaline, which speeds up the heart and breathing rate. This reaction increases the oxygen sent to muscles, giving someone a temporary energy boost. 

"A full grown man with adrenaline could — in that situation — pry open a 200-pound vise essentially," Gignac said. "I think it would be difficult but, you know, when you don't really have any other choice, you go for it. So it's not out of the realm of possibility." 

So what should you do if you find yourself in a fight with this apex predator? 

"If you have an object with you, and you have the wherewithal to go for the eyes, that's probably the most sensitive place on [the] head of a crocodile or an alligator," Gignac said. "My best advice is to not get yourself into a scenario where you have to fight off an alligator or a crocodile."

Freshwater mugger crocodiles and gharials are turning orange in Nepal, and scientists think it's down to iron in the waters where they hang out.

The orange crocs were spotted in Chitwan National Park, a protected area of the Himalayan foothills. "Have these crocs been drinking too much Sunny D? Messily eating Cheetos? Or could they be taking fashion advice from Donald Trump?" Phoebe Griffith, a postdoctoral researcher at the Leibniz Institute of Freshwater Ecology and Inland Fisheries, wrote in a Twitter thread on May 29. 

To find out why the crocs have become tangerine-colored, researchers collaborated with Project Mecistops — a conservation project working to preserve and reintroduce critically endangered West African slender-snouted crocodiles (Mecistops cataphractus) in Côte d'Ivoire and throughout western Africa. 

It turns out some of the rivers and streams in the park have extremely high levels of iron, which could explain why some crocodilians are sporting orange coats.

"Gharial and mugger crocodiles who spent lots of time in some streams, or near the mouths of them, were getting a serious fake tan," Griffith explained on Twitter. "Turns out some areas of Chitwan have seriously high levels of iron in the water, and iron reacts with oxygen to form an orange substance called iron oxide."

Related: How are alligators and crocodiles different?

As these crocs spend most of their time in the water — gharials are not well-suited to walking on land and typically only crawl onto sandbanks to bask in the sun or nest — the iron-rich rivers could have coated their scales and teeth in a temporary layer of rusty particles.

Gharials (Gavialis gangeticus) are critically endangered freshwater crocodiles that have a long, narrow snout tipped with a bulbous growth. Males can grow to be around16 feet (5 meters) long and weigh up to 550 pounds (250 kilograms). 

The gharial population in Nepal has plummeted by 98% since the 1940s due to overhunting, according to the Zoological Society of London. Most of the 200 remaining gharials live in Chitwan National Park, where they face additional threats linked to pollution, mining and declining fish populations.

Mugger crocodiles (Crocodylus palustris) are more widespread and inhabit marshes and waterways stretching from southern Iran to the Indian subcontinent. They are broad-snouted and similar in size to gharials, but they can weigh twice as much due to their girth. 

The discolored gharials’ and crocodiles’ new orange look is temporary, and the rusty particles could wash off in less iron-rich waters. "It should go off automatically in clean(er) water," Lala Aswini Kumar Singh, a zoologist and wildlife researcher in India, wrote in a comment on Twitter.

These aren't the first rust-colored reptiles on record. A 2016 study in the African Journal of Ecology reported that orange dwarf crocodiles (Osteolaemus tetraspis) living in caves in Gabon may have turned orange after being exposed to bat guano, which contains high levels of urea — a substance with a bleaching effect that forms when protein is broken down in the liver.

Iron oxide may also have tinted an orange-hued alligator in South Carolina in 2017, after it spent the winter in a rusty iron culvert. 

An idyllic beach in Australia turned into a nightmare scene earlier this week, when locals discovered an enormous, beheaded crocodile rotting in the sand.

Some residents think the mutilation could have been an act of vengeance following a recent spate of crocodile attacks against humans along the Queensland coast between Port Douglas and Cooktown, according to news.com.au. But it's still unclear how the 13-foot-long (4 meters; including the head) giant died, according to the Queensland Department for Environment and Science (DES).

The carcass was in such a state of decay that staff were unable to conduct a necropsy, the government agency said. "Due to the state of decomposition, it cannot be determined if there has been any human interference," the DES told Live Science in a prepared statement. "It may be that the crocodile was decapitated (pre- or post-mortem) due to natural predation."

Some locals, however, doubt that another crocodile decapitated the enormous animal and suspect that it was slaughtered in a trophy killing.

"The DES claim is absolutely ridiculous," Tom Chalmers Hayes, a crocodile photographer and conservationist who went to the scene following reports of the dead animal, told Live Science in a message on social media. "I was with the body for three hours and there is absolutely no marking to suggest a crocodile has killed this male and torn it up, very clear machete marks are on the body and around the neck area where the head has been removed."

Related: Giant 14-foot-long crocodile found with human remains in stomach 

The headless crocodile was found on Cow Bay Beach, north of the Daintree River. Based on its size, the large male is considered an "icon" crocodile under Queensland's conservation laws, which means that it is more strictly protected than smaller individuals. Herpetologists estimate it was at least 30 to 40 years old and a top predator.

The loss of a gigantic male like this one could unsettle the social order of other crocodiles in the area. "As we're only beginning to understand the social system of crocodiles, it is difficult to predict how the removal of a single large male crocodile will impact the remaining crocodiles in the area," Cameron Baker, a postdoctoral researcher at Charles Darwin University in Australia who is not involved in the beheading investigation, told Live Science in an email. "However, it will likely represent a period of social unrest and change in the population as individuals try to determine where they sit in the new social hierarchy resulting from this large male's loss."

Conflict could arise between several males vying to replace the dead individual, although crocodiles may not be as territorial as scientists once thought, Baker said.

The killing could also have a ripple effect on the coastal ecosystem. "As top predators, crocodiles potentially play several crucial roles in their environment," Baker explained. "For instance, by limiting the population density and behavior of their prey species, crocodiles inadvertently enhance the survival of their prey's prey. As such, the removal of crocodiles through hunting may unintentionally alter the composition of the ecosystem, reducing its overall health and productivity."

Crocodiles in Queensland have come back from the brink of extinction since the 1970s, when hunters killed them for their skins, according to a 2020 DES report. But they are still listed as a vulnerable species by the DES under the state's Nature Conservation Act 1992.

The beheading follows three serious but non-fatal crocodile attacks on people in the area since February. The last incident occurred on April 8, when a nearly 15-foot-long (4.5 m) croc repeatedly bit a man and nearly drowned him at Archer Point, south of Cooktown. The man managed to escape by sticking his fingers in the animal's eyes.

On Aug. 4, Port Charlotte resident Tammy Shaw was paddleboarding in Silver Springs State Park in Florida, when she discovered a gruesome scene of cannibalism and carnage. A sizable alligator crouched in the spring just a short distance from Shaw's inflatable boat, and clasped in its jaws was the limp body of another alligator — the bigger predator's next meal, News 6 Orlando reported.

As Shaw watched, the large gator lifted its head higher and then slammed its unresponsive prey into the water. 

Shaw captured a short video of the gators and posted it in the Facebook group Alligators of Florida on Aug. 10. Commenters were shocked that an alligator would eat another alligator. "I never knew they would actually eat one of their own," one person wrote.

Yet cannibalism is not at all uncommon in alligators, Adam Rosenblatt, an assistant professor of biology at the University of North Florida who studies American alligators (Alligator mississippiensis), told Live Science in an email. Alligators eat other alligators for the same reason they eat anything else, he explained — they get hungry.

Related: Human remains found inside 500-pound alligator. How common are alligator attacks?

"Alligators will eat anything they can fit their jaws around, including mammals, birds, reptiles, amphibians, fish, insects, crustaceans, snails, and even fruits and seeds sometimes," he said.

It's also possible for alligators to eat other alligators that invade their territory, Rosenblatt added. Large male alligators, in particular, are often solitary and territorial, according to the conservation nonprofit Defenders of Wildlife.

Alligators are master hunters, and not only when it comes to eating other alligators. They often simply swim directly up to small prey, like crabs and shrimp, and immediately gulp them down, Rosenblatt said, but with larger prey, such as pigs and deer, alligators can be very stealthy. Gators sometimes wait in the water for hours for big animals to approach to get a drink, before slowly advancing to avoid notice and then suddenly striking when they are 3 or 4 feet (about a meter) away.

"They'll grab the prey by the head or by a leg, whatever the gator can get its mouth on, then drag the prey into the water to drown it," Rosenblatt said. Alligators also sometimes do a "death roll," where they quickly roll while holding prey, often breaking the prey's neck or legs. Gators also kill turtles by using their powerful jaws to crush the turtles' shells, he said. Alligators devour small prey whole, but with large prey, they vigorously shake it — as demonstrated by the bigger alligator in Shaw's video — so that it will more easily break up into smaller pieces, according to the Smithsonian's National Zoo and Conservation Biology Institute. If the prey is very large, alligators use their death roll to tear it apart.

Though cannibalism is taboo in most modern human cultures, it's very common among many animals, Rosenblatt said. For example, lions and chimpanzees are also known to eat their own kind. But even if people are squeamish about such observations, alligators won't be changing their cannibal dining habits anytime soon.  

"Alligator cannibalism has occurred for millions of years and will continue to occur," Rosenblatt said. "There's no reason to expect its frequency to change in the near future."

Originally published on Live Science.

Most people think of fishing as a relaxing way to pass an afternoon. But for YouTuber and conservationist Payton Moore, a recent fishing excursion was instead an intrepid monster hunt.

Last week, the Texan set sail down a Houston bayou in search of a truly gargantuan alligator gar (Atractosteus spatula) stretching over 8 feet (2.5 meters) long and tipping the scales at an estimated 300 pounds (136 kilograms). He found what he was looking for —and he even managed to catch the gigantic fish. "It felt like somebody's car had just started up and was rolling out of the driveway, and I’m hanging on to the end of it," Moore told the Houston Chronicle in an interview.

After hauling the fish ashore and measuring it, he released the gar back into the wild. Then he uploaded a video of the catch to his channel, WILD LIFE on May 7.

Related: Amazon 'river monster' turns up dead in Florida

"This was an excellent specimen," Nate Smith, a research biologist at the Texas Parks and Wildlife Department who researches alligator gar, told Live Science. "It’s hard to say what the exact weight was without more precise measurements or an official scale, but it's obviously a big fish." 

Officially, the largest alligator gar ever caught in Texas weighed in at 302 pounds (137 kg), according to Texas Parks and Wildlife. It was captured in 1953 on a trotline — a heavy line with shorter baited lines attached along its length at regular intervals. Moore's catch may have outweighed the previous champ, but since he did not seek official certification, his fish isn't record-eligible.

Gars belong to an ancient lineage of fish that were once widespread across the globe. Fossil remains of extinct gar dating back to the Cretaceous period (145 million to 66 million years ago) have been unearthed in Europe, Africa and south Asia, according to the Florida Museum. Only seven species are still around today.

Alligator gar, the largest of the extant gar species, are among the biggest freshwater fish in North America, according to National Geographic. They live exclusively in the lower Mississippi River Valley, where they chow down on smaller fish, blue crabs, waterfowl and the occasional turtle. While a fully-grown alligator gar may look intimidating, they pose no threat to humans. However, like other gar, their eggs are toxic to people and should not be eaten.

Historically, gar have been targeted by culling efforts by various state and federal agencies to make more room for game fish. But recent years have seen an increase in conservation efforts from organizations like the Texas Parks and Wildlife Department. Though there are few prohibitions on gar fishing (aside from a one-fish-per-day limit on alligator gar), Smith recommended that anglers interested in catching gar take a catch-and-release approach.

"One cool thing about alligator gar is that they can actually breathe air," Smith said. "For that reason, it's OK to have the fish out of the water for a few minutes for measurements or photos, just be sure to keep them cool and wet, especially in the hot sun."

Moore hopes that by sharing his video of the gargantuan gar he will help spark an appreciation for nature in all who see the massive fish. "They're so rare now, unfortunately," he said in his video. "It's an honor to share a wild space like this with an incredible wild animal like that."

Originally published on Live Science.

Crocodiles are large reptiles found in tropical regions of Africa, Asia, the Americas and Australia. They are members of the order Crocodilia, which also includes caimans, gharials and alligators. 

There are 13 crocodile species, and they range in size. The smallest, the dwarf crocodile (Osteolaemus tetraspis), grows to about 5.6 feet (1.7 meters) in length and weighs 13 to 15 pounds (6 to 7 kilograms), according to the Zoological Society of London. The largest, the saltwater crocodile (Crocodylus porosus), can grow up to 23 feet (6.5 m) in length and can weigh up to 2,000 pounds (907 kg), according to Oceana.org.

What do crocodiles eat?

Crocodiles are carnivores, which means they eat only meat. In the wild, they feast on fish, birds, frogs and crustaceans. Occasionally, crocs cannibalize each other. In captivity, they eat small animals that have already been killed for them, such as rats, fish or mice. They also eat live locusts, according to The Australian Museum.

In the wild, crocodiles clamp down on prey with their massive jaws, crush it and then swallow the prey whole. They cannot chew or break off small pieces of food as some other animals do.

To help with digestion, crocodiles swallow small stones that grind up the food in their stomachs. Thanks to their slow metabolism, crocodiles can survive for months without food.

Where are crocodiles found?

About 100 million years ago, during the Mesozoic era, the Crocodilia order included some of the top animals in the food chain. Today, crocodiles are found in tropical regions of Africa, Asia, Australia and the Americas. They normally live near lakes, rivers, wetlands and even some saltwater regions. 

Crocodiles live in tropical climates because they are cold-blooded and cannot generate their own heat. During colder months, they enter a hibernation-like state of inactivity known as aestivation, which involves slowing down all bodily processes, according to Animalia. Crocodiles also aestivate during long periods of drought. To create a place to hibernate, they dig out a burrow in the side of a riverbank or lake and settle in for a long sleep.

Are crocodiles dinosaurs?

Though they share many characteristics and appeared on the planet during the Mesozoic era, crocodiles and dinosaurs are not the same. 

Dinosaurs and crocs both belong to a reptile subclass known as archosaurs, which first appeared in the fossil record about 250 million years ago, during the Triassic period. By the end of the Triassic, archosaur evolution split into two paths: One branch of archosaurs evolved into the oldest relatives of crocodiles and alligators, and the other branch evolved into dinosaurs, birds and flying reptiles (also known as pterosaurs). 

About 66 million years ago, at the end of the Cretaceous period, a mass extinction wiped the nonavian dinosaurs and flying reptiles off the planet. Today, crocodilians and birds are the only surviving archosaurs.  

Baby crocodiles

Crocodiles lay an average of 12 to 48 eggs at a time. The hatchlings stay in their eggs for 55 to 100 days. The sex of each crocodile baby depends on the temperature of its egg during a critical moment during the first half of its incubation period.

Crocodile babies measure about 7 to 10 inches (18 to 25 centimeters) long when they are born and don't mature until they are 4 to 15 years old. How long a crocodile lives depends on its species; some, such as the Dwarf crocodile, live to around 40 years, while others, such as the Nile crocodile, live up to 80 years, according to Animalia.

Are crocodiles endangered?

The Cuban crocodile is one of the world's most endangered species of crocodile. It is considered critically endangered and has a population of only about 4,000, according to the International Union for Conservation of Nature (IUCN). Poaching is a constant threat to the species. 

The American crocodile is considered vulnerable by the IUCN, but its population is increasing.

Alligators vs. crocodiles

How are alligators and crocodiles different? For one, an alligator's jaw is U-shaped, while a crocodile's is V-shaped, Live Science previously reported. In addition, crocodiles' teeth stick up over their upper lip when their mouths are closed, whereas alligators' teeth do not.

Another difference between alligators and crocodiles is that crocs have salt glands on their tongues. These modified salivary glands help crocs tolerate life in salt water. Alligators and caimans have lost the ability to secrete excess salt through the tongue glands and, therefore, prefer to live in freshwater areas, according to the Crocodilian Biology Database.

Crocodile taxonomy

Here is the taxonomy of crocodiles, according to the Integrated Taxonomic Information System (ITIS):

Facts about crocodiles

• When a crocodile loses a tooth, it is quickly replaced. These reptiles can go through 8,000 teeth over a lifetime, according to the San Diego Zoo.
• Crocodiles don't sweat. To keep cool, they open their mouths in a process called "mouth gaping," which is a lot like panting.
• "Crying crocodile tears" refers to a person expressing insincere remorse. It is a saying that goes back to about the 16th century. However, crocodiles do in fact produce tears, according to the Crocodilian Biology Database. Their lacrimal glands secrete a fluid behind their third eyelid, called a nictitating membrane. The fluid helps clean the eye, lubricate it and reduce bacteria. Crocodile tears aren't usually noticeable unless the croc has been out of the water for a while and the eyes begin to dry out.
• A crocodile's jaws can apply 3,700 pounds of pressure per square inch, according to National Geographic. This means that they can bite through a human arm or a leg with no problem. For comparison, a human jaw produces only about 100 pounds of pressure per square inch. The crocodile jaw has very little opening strength, though; a crocodile's mouth can be held shut with just a rubber band.
• In addition to their strong jaws, crocodiles have very keen hearing. It is so good, in fact, that they can hear their babies calling from inside their eggs.
• Crocodiles are very fast swimmers, which helps them catch their prey. They can swim up to 18 mph (29 km/h) and hold their breath underwater for around one hour, according to Australia’s Northern Territory government. Crocodiles aren't as fast on land, where they can run only up to 11 mph (18 km/h) for a short distance.

Nina Sen contributed to this article. This article was updated on Mar. 4, 2022, by Live Science Senior Writer Brandon Specktor.

Additional resources

Learn more fun crocodile facts from the San Diego Zoo's crocodilian info page. Read more about crocodile conservation and the conservation status of different crocodile species via the IUCN. Concerned about crocodile attacks on humans? Check out CrocBITE, the worldwide database of crocodilian attacks.

Bibliography

Britton, A. (n.d.). Crocodilian Biology Database. Retrieved February 28, 2022, from http://crocodilian.com/cnhc/cbd-faq-q1.htm

Handwork, B. (2012, March 15). Crocodiles have strongest bite ever measured, hands-on tests show. National Geographic. https://www.nationalgeographic.com/animals/article/120315-crocodiles-bite-force-erickson-science-plos-one-strongest

Integrated Taxonomic Information System. (n.d.). Crocodylus. Retrieved February 28, 2022, from https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=174360#null

Northern Territory Government. (2016, July 4). Be CrocWise. https://becrocwise.nt.gov.au/about-crocodiles/did-you-know 

Ross, J. P. (2008, June 13). Crocodile. Britannica. https://www.britannica.com/animal/crocodile-order 

San Diego Zoo Wildlife Alliance. (n.d.). Crocodilian. Retrieved February 28, 2022, from https://animals.sandiegozoo.org/animals/crocodilian 

Targarona, R. R., Soberón, R. R., Cotayo, L., Tabet, M. A. & Thorbjarnarson, J. (2008). Cuban Crocodile. The IUCN Red List of Threatened Species 2008. https://dx.doi.org/10.2305/IUCN.UK.1996.RLTS.T5670A11516438.en. Retrieved on February 28, 2022.

Zoological Society of London. (n.d.). Dwarf crocodile. Retrieved February 28, 2022 from http://www.edgeofexistence.org/species/dwarf-crocodile/

A 13-foot-long (4 meters) crocodile on an Indonesian island has been freed from an unflattering and potentially harmful motorbike tire that had been stuck around its neck for at least six years. A local man who captured the behemoth in a handmade trap managed to remove the rubbery necklace. 

The lengthy crocodile lives in a river near the city of Palu on the island of Sulawesi and is known by locals as "buaya kalung ban," meaning "crocodile with a tire necklace." Individuals first spotted the croc in 2016, and since then local conservationists have made two failed attempts to catch the animal and remove the tire. Professional crocodile wranglers from Australia also flew to Indonesia to try to catch the elusive reptile, but came up empty-handed, according to ABC News. 

On Feb. 7, a 35-year-old local man named Tili finally managed to catch the crocodile in a makeshift trap, which consisted of a rope tied to a log with live chickens and ducks being used as bait. Tilli had been tracking the croc for the previous three weeks and came close to catching his target on two occasions before finally snagging the slippery critter, according to Reuters.

Related: How did the massive 'Salty' crocodile captured in Australia get so freaking big?

"Many people were skeptical about me and thought I was not serious," Tili told Reuters. "I was asking for help from people here, but they were scared."

After Tili caught the crocodile and dragged it to shore, a large group of locals, including firefighters, assembled to watch and assist in cutting the tire free from the reptile's scaly neck. After being liberated, the crocodile was released back into the river. Video of the rescue was shared on Twitter by RTE News.

In January 2020, a local conservation group offered a reward to anyone who could catch the crocodile and help free it. However, Tili claims he did not do it for the money. "I just can't stand to see animals hurt," Tili told Reuters. "Even snakes, I will help."

Originally published on Live Science.

Around 155 million years ago in what is now Wyoming, a crocodile relative clamped its jaws around a thrashing animal and dragged it below the water's surface, and the ancient reptile could still breathe comfortably as its prey slowly drowned.

That's because the croc had specialized structures that prevented water from flowing through its mouth and into its airway. This feature is known in modern crocodilians — crocodiles and their close relatives — and scientists recently identified the same mechanism in a newly described species of croc cousin that lived during the Jurassic period (201.3 million to 145 million years ago).

This is the earliest evidence of crocodilian adaptations for submerging their heads (and prey) underwater while still being able to breathe through nostrils on top of their snouts; this ability is an important part of the group's deadly feeding habits today, and may have helped crocodilians survive the Cretaceous extinction that wiped out most of the dinosaurs.

Related: Crocs: Ancient predators in a modern world (photos)

Scientists named the newfound species Amphicotylus milesi, and it belongs to a group of early crocodile relatives called goniopholidids, which lived in the Northern Hemisphere from the Jurassic through the early Cretaceous period (145 million to 66 million years ago) and had a body plan suggestive of a semiaquatic lifestyle. 

The near-intact skeleton, discovered in 1993 in Wyoming's East Camarasaurus Quarry, is the most complete goniopholidid fossil ever found. When it was alive, the reptile would have measured about 7.5 feet (2.3 meters) long and weighed up to 500 pounds (227 kilograms), study co-author Michael J. Ryan, an adjunct research professor in the Department of Earth Sciences at Carleton University in Ontario, told Live Science in an email. 

A. milesi also has one of the biggest known skulls among this group of early crocs, measuring 17 inches (43 centimeters) long, and the broad, elongated snout accounts for about 60% of the skull length, the scientists reported Dec. 8 in the journal Royal Society Open Science. However, unfused sutures in some of the bones hint that the reptile was a youngster that was still growing, according to the study. 

"I believe that it was approximately adult size, but reptiles like this would have had indeterminate growth — continuing to grow through their lives, but slowing down after maturity," Ryan said. "A conservative estimate would be that an 'adult' could have been half again as long and heavy," measuring nearly 12 feet long (3.7 m) and weighing up to 750 pounds (340 kg), he added. 

Breathe deep

Modern crocodilians — crocodiles, alligators, caimans and gharials — can breathe through their mouths and through nostrils on top of their snouts. The nostrils have protective valves at the openings, and air travels through canals and down the back of the throat, where it passes through another valve, according to the IUCN-Species Survival Commission's Crocodile Specialist Group (CSG), a global network of experts involved in crocodilian conservation.

When a crocodilian basks on land, it typically breathes through its open mouth, and the palatal valve in the throat (also known as a gular flap) is open. However, when it is holding prey in the water, the crocodilian breathes through its nostrils and the flap is closed, which prevents the animal from inhaling water through its open mouth, according to the CSG. When this flap isn't in use, it rests in the underside of the throat, and a network of muscles lifts the flap into place to block the flow of water.

Related: Photos: Early dinosaur cousin looked like a croc

As the researchers examined the size, shape and curvature of skull structures in A. milesi, they found similarities to certain features in modern crocodiles with the gular flap, such as an extension in the roof of the mouth toward the back of the throat and a shortened bone called the ceratobranchial, which lies in the throat and supports the tongue. This combination of anatomical features in A. milesi suggests that this ancient croc relative also had a flap that would have kept it from inhaling water while drowning its prey, so long as it kept its nostrils above the water, the study authors reported. 

Other crocodilian relatives dating to the late Jurassic and early Cretaceous periods have similar modifications, "suggesting that they, too, may have had a similar ability," Ryan said. "But this combination of anatomical features is unique to Amphicotylus."

Adaptations for underwater dining could help to explain why the ancestors of modern crocodiles were able to weather the mass extinction event at the end of the Cretaceous period while their nonavian dinosaur contemporaries died out, Ryan explained.

"The features now recognized in Amphicotylus allowing for a feeding strategy that nonavian dinosaurs did not have might have contributed to their survival of the Cretaceous extinction — by staying and feeding in the water," Ryan said.

Originally published on Live Science

All alligators and crocodiles belong to a taxonomic order called Crocodylia. Crocodylia is then split up into three major families; Alligatoridae (alligators), Crocodylidea (crocodile) and Gavialidae (gharial), according to the journal Pathology of Wildlife and Zoo Animals. 

These Crocodylia share a common evolutionary ancestor; however, around 80 million years ago - during the Late Cretaceous period - Alligatoridae and Crocodylidae diverged and continued along their own evolutionary journey, according to the New York Times. Over millions of years of evolution, both crocodiles and alligators have remained relatively similar in their appearance, but there are some surprising differences that are easy to spot. 

Related: Mystery of extinct horned crocodile solved after 150 years

Do alligators and crocodiles look different?

At first glance, crocodiles and alligators look quite similar; however on closer inspection, the two have very different snouts. There is one quick-fire way to distinguish a crocodile from an alligator: Look at their jawline. Alligators have an overbite, and so the teeth on the bottom jaw fit into sockets in the top jawline and are concealed. The teeth on the bottom row of a crocodile's jaw, on the other hand, sit on the outside of the mouth and slot into grooves along the top jaw, according to Biology and Evolution of Crocodylians. The shape of their heads is also a key identifier. Alligators have a U-spaced rounded snout that is  wide and short, whereas crocodiles have a longer pointed, V-shaped snout. There are some exceptions to the rule, such as the mugger crocodile (Crocodylus palustris), which has a rounded snout reminiscent of an alligator, according to San Diego Zoo Wildlife Alliance. 

Both of these reptiles have tiny black specks called integumentary sense organs (ISOs) on their heads. These sensory organs allow the predators to detect pressure changes in the water caused by potential prey. ISOs can be found solely on the head and around the mouth of alligators; crocodiles have ISOs on almost every scale on their body, according to the Journal of Experimental Biology.

Differences between the two reptiles are also much more than skin deep. In a study published in 2018 in the journal Royal Society Open Science, researchers found that, compared with crocodiles, the forelimbs of alligators have a shorter humerus bone and hindlimbs have shorter femurs.

Where do crocodiles and alligators live?

One major difference between alligators and crocodiles is where they live. Crocodiles have lingual salt glands - on their tongues - which allow them to expel excess salt from their bodies, according to a study published in the Journal of Comparative Physiology. This ability allows them to live in salty marine environments, such as Australia's saltwater crocodiles (Crocodylus porosus) - which reside throughout mangroves, swamps and deltas. Although alligators have the same salt gland, that gland is not very effective and limits the alligator's tolerance for salt water. Therefore, alligators stick to freshwater habitats, such as lakes and marshes. 

This difference in salt tolerances could also explain differences in their global distribution. Crocodile species can be found across the Americas, Africa, Asia and Australia, whereas alligators are predominantly found in North and South America, according to National Geographic. 

Related: Alligators can regrow their tails, surprising scientists

Additional resources

• For more information about the evolution of crocodiles and alligators check out: The Rise of Reptiles: 320 Million Years of Evolution
• Herpetology: An Introductory Biology of Amphibians and Reptiles
• Discover the population status for crocodiles and alligators at the International Union for Conservation of Nature (IUCN) Red List

An enormous alligator is suspected of killing a man in Louisiana, according to news reports. 

Officials from the U.S. Fish and Wildlife Service and the Louisiana Department of Wildlife and Fisheries recently captured the alligator around the neighborhood of Avery Estates, not far from where 71-year-old Timothy Satterlee Sr. went missing on Aug. 30, the St. Tammany Parish Sheriff's Office wrote on its Facebook page. The 12-foot-long (3.7 meters), 504-pound (229 kilograms) alligator had "what appears to be human remains inside its stomach," according to the post.

Satterlee's wife reported to the police that an alligator had attacked her husband outside their home in floodwaters from Hurricane Ida, according to The Charlotte Observer. She tried wrestling him from the alligator's grip and pulled him onto the front steps of their house, before leaving to look for help. But when she came back to the house, he was gone. The investigators will now work with the coroner's office to confirm the remains belong to Satterlee, according to the Facebook post.

How common are such tragic alligator attacks?

Related: Alligator alley: Pictures of monster reptiles

"People getting killed by alligators is extremely rare," said Adam Rosenblatt, an assistant professor of biology at the University of North Florida who studies how alligators respond to changing environments. 

Between 1999 and 2019, alligators killed 10 people in the southeastern U.S., according to data from the Centers for Disease Control and Prevention. In that same time period and in the same area, nearly five times as many people were killed by dogs, and nearly 12 times as many people were killed by lightning, he said.

"A lot of human-alligator conflict occurs when alligators get provoked, both intentionally and unintentionally, or when alligators go after people's pets," Rosenblatt told Live Science. When hungry, alligators might go after people, but those types of situations are "rarer," he said.

Worldwide, alligators are responsible for less than 6% of fatal attacks by animals in the group called crocodilians (which includes crocodiles, alligators, caimans and gharials), according to the University of Florida. Around 4% of alligator attacks on humans in the U.S. have led to death.

There's no evidence to suggest that alligators change their behaviors and actively hunt during hurricanes in Florida, according to the University of Florida. But they may show up in unexpected places due to widespread flooding after a hurricane.

Though rare, fatal alligator attacks do occur from time to time. People can limit their chances of such a conflict by not approaching alligators when they see them; walking pets at a distance from lakes and ponds; avoiding swimming in areas that are known to have alligators, especially at night; and never feeding them, Rosenblatt said.

Originally published on Live Science.

What's tiny, toothy and devoid of pigment? Two new baby albino alligators born at a wildlife attraction in Florida. 

The rare reptiles hatched this summer at Wild Florida in Kenansville, Florida. They're the babies of 27-year-old Snowflake and 16-year-old Blizzard, a pair of albino alligators the zoo and safari park purchased in 2017. This is the second set of hatchlings born to Snowflake and Blizzard, who also had a pair of babies last year according to Wild Florida.

Albinism is a condition marked by a lack of pigmentation in the skin, eyes, claws and (in mammals, at least) hair. There are probably only about 200 albino alligators in the world, according to the South Florida Sun-Sentinel. Not only does their pink-white skin predispose them to dangerous sunburns, but their lack of camouflage is a real disadvantage.

"They're like candy canes," said Joe Wasilewski, a wildlife biologist and member of the International Union for Conservation of Nature (IUCN) crocodilian specialist group. In other words, they're highly visible and tasty to predators ranging from birds to adult alligators. 

Rare find 

The hatchlings' eggs were two of 18 collected from their mother Snowflake on April 30, 2021. The eggs were put in an incubator for about 60 days to keep them at a stable temperature and increase the chances of survival. The genetic mutations that cause albinism tend to make animals less hardy in general, Wasilewski told LIve Science. 

The new babies are part of a decades-long history of albino alligators at attractions in Florida, Louisiana and other gator farms. Alligators were once endangered, Waskilewski said, but conservation and management has grown their numbers to high levels — 1.2 million in Florida alone. For that reason, many states now issue permits for alligator hunting and egg collection from the wild. This keeps alligator population numbers sustainable in the amount of habitat available to them, Wasilewski said. As part of this program, some licensed facilities and individuals are allowed to harvest, purchase and breed alligators.

The family line of the new babies hails from Louisiana, where a permitted egg collector found a nest with several albino babies in the 1990s. The Saint Augustine Alligator Farm Zoological Park in Florida bought the rights to harvest the nest in subsequent years (gators nest in the same area year after year). Wild Florida purchased Snowflake and Blizzard from the Saint Augustine Alligator Farm.

There's no real conservation advantage to owning or breeding albinos or other alligators with unusual coloration, Wasilewski said, but they're a tourist draw.

"It's kind of like designer alligators, you can buy a regular alligator, if you're licensed, for $50 or you can buy an albino for $15,000," he said.

Alligators on display

The new babies are small enough to be picked up in one hand, with red eyes and barely visible yellow and pinkish stripes along their white backs. They're not on public display yet, but they will soon be moved to an aquarium in the gift shop, according to the Sun-Sentinel. The babies can't be kept with their parents, zoo co-owner Sam Haught told the newspaper, lest the mother decide to snack on them. 

Albino alligators have to be sheltered more than non-albino alligators do, Haught added, so they'll live in climate-controlled habitats. 

"Because of their albino skin, they get sunburned really easily. And they don’t know they’re albino," Haught told the Sun-Sentinel. "So, they’ll sit out in the sun all day and get sunburned and kill themselves, basically."

Zoos like Wildlife Florida have to abide by regulations such as caging requirements, according to the state Fish and Wildlife Conservation Commision. Because of their decreased hardiness, it's hard to breed albino alligators, Wasilewski said. The fact that Snowflake and Blizzard have produced viable eggs suggests they're healthy and being treated well, he said. Similar wildlife attractions in Florida also have odd-colored alligators, Wasilewski said. Gatorland in Orlando, for example, is home to several albino alligators as well as a pair of leucistic alligators, which have a partial loss of pigmentation. Albino alligators have a total loss of pigmentation, causing their eyes to turn pink, while leucistic alligators have white bodies and blue or black eyes. In captivity, these unusual alligators can live for decades. 

The zoo posted a video of the brand-new babies on Facebook on Aug. 10.

Originally published on Live Science.

After almost 150 years of controversy, scientists have finally solved the classification mystery surrounding the extinct horned crocodile and determined exactly where this cryptic croc belongs on the tree of life.

The extinct horned crocodiles (Voay robustus) were endemic to Madagascar as far back as 9,000 years ago and lived as recently as 1,300 to 1,400 years ago, according to fossil evidence. First discovered in 1872, the beasts are named for the distinctive horns on their skulls. Since their discovery, they have been classified in several different families, confused for other species and given several different names, with no clear evolutionary origin of their own.

In the new study, researchers from the American Museum of Natural History (AMNH) in New York City used DNA analysis to shed light on these ambiguous reptiles and determine whether they belong to their own unique group. 

Related: Top 10 deadliest animals (photos)

"The DNA tells a different story," lead author Evon Hekkala, an AMNH associate at Fordham University in New York, told Live Science. "It tells us over and over again that appearances can be deceiving."  

Complicated history 

Madagascar is currently home to Nile crocodiles (Crocodylus niloticus), which are invasive to the island nation. The earliest evidence of Nile crocodiles in Madagascar is 300 years old, but Malagasy tales suggest that they may have migrated there much earlier and lived alongside horned crocodiles, Hekkala said.

Horned crocodiles were not particularly large crocs, but their heavyset skulls suggest they were likely a'robust,a' which led to their species name robustus, Hekkala said. "We don't have any complete skeletons, but they weren't spectacularly long," Hekkala said. "Based on the size of their skulls, they were likely similar in overall size to Nile crocodiles."

A number of other larger animals — including giant tortoises, elephant birds, dwarf hippos and several lemurs — also went extinct on the island around the same time as horned crocodiles did, but it is unclear what caused their demise, according to an AMNH statement. 

It may have been due to the arrival of the invasive Nile crocodiles or more likely the arrival of the first humans on Madagascar as late as 2,500 years ago, according to the researchers. However, natural climate change also may have played a role.

"Some recent studies have indicated that parts of the island became drier," Hekkala said. "It could be that this benefited the newly arrived Nile crocodile and made the island more inhospitable to the endemic horned crocodile."

Classification nightmare 

The limited fossil record and incomplete ecological history of Madagascar partly explain why it has taken almost 150 years to successfully place the horned crocodiles in their own evolutionary group. In addition, crocodile species are very similar physically, especially in their skulls, which scientists have historically used to classify them. But skull variations between individuals within the same species can be high, which can often make them appear to be from another species.

"Crocodile head shape varies dramatically with age, sex and even diet," Hekkala said. "So a large, old crocodile skull might look really distinct."

When the horned crocodiles were originally discovered, scientists classified them as true crocodiles — a subfamily containing Nile crocodiles and other modern-day crocodiles like the American crocodile (Crocodylus acutus) and saltwater crocodile (Crocodylus porosus) — and were given the name Crocodylus robustus.

This confusion was magnified in 1910 when a popular illustration of what a horned crocodile may have looked like was released in a scientific article, Hekkala said. Unfortunately, the image actually depicted a modern-day Nile crocodile, but it helped to solidify the theory that the horned crocodiles were true crocodiles. Some even argued that the horned crocodiles may just have been an ancestor of Nile crocodiles. 

This remained the general consensus until 2007 when researchers analyzed the skulls of horned crocodile fossils to reveal significant physiological differences compared with those of Nile crocodiles. After this revelation, the horned crocodiles were put into a new subfamily called dwarf crocodiles — smaller crocodiles with short, stout skulls that diverged from the true crocodiles millions of years ago. The horned crocodiles were also given a new genus name, Voay, which means "crocodile" in the Malagasy language.

In the new study, AMNH researchers instead analyzed DNA evidence to determine which group the horned crocodiles really belonged to.

A new group 

DNA analysis revealed that the horned crocodiles were not dwarf crocodiles like the 2007 study had suggested nor were they true crocodiles like earlier naturalists assumed. Instead, they belong to their own unique genus.

"What surprised us at that point was that it was not grouped within the true crocodiles, but adjacent to it," Hekkala said. "This makes it a bit like a long-lost lineage that was isolated on an island."

The fact that this new group, which is closely related to true crocodiles, was endemic to Africa also suggests that this may be where crocodiles first evolved, which is the leading theory in the field. "Our data support the hypothesis that the modern crocodiles we see today originated in Africa," Hekkala said.

Getting to the bottom of the evolutionary mystery surrounding horned crocodiles is important because it helps scientists to build a better picture of how modern-day animals evolved and how they may be able to adapt to change, Hekkala said.

"Extinct species can act as bridges over knowledge gaps," Hekkala said. "They help us to time travel and to reconnect evolutionary histories to tell the story of life and extinction on Earth."

The study was published online April 27 in the journal Communications Biology. 

Originally published on Live Science.

Oklahomans came face-to-face with popsicle-like alligators — reptiles whose snouts were sticking straight out of the icy water — when the cold snap hit the American South this month.

But why were these alligators "snorkeling" in such cold weather? Why weren't they sunning on the banks or hiding in their burrows?

And who knew Oklahoma even had alligators? The news of the snorkeling alligators sparked a debate on Facebook over whether alligators (Alligator mississippiensis) were a native or introduced species to the state. According to an 1866 description of an alligator written in an Oklahoman man's diary, it appears that they are native, although other alligators have been introduced to wetlands in the state's southeastern corner since then, said Jena Donnell, the Wildlife Diversity Communication Specialist with the Oklahoma Department of Wildlife Conservation.

As for the alligator's weird snorkeling behavior, it's completely normal, Donnell told Live Science. "Whenever it ices over, this is a natural response [seen in alligators]," she said. "Since the water they were in froze over, they had to create a 'snorkel,' so they tipped their nose out of the water to keep some ice-free water, so they're still able to breathe."

Related: Alligators vs. crocodiles: Photos reveal who's who

Alligators are cold-blooded, or ectothermic creatures, which means their body temperature fluctuates with the ambient temperature. That's why alligators are often found basking in the sun or camping out in burrows with air pockets that they've dug into the banks of lakes and waterways.

When freezing temperatures hit their habitats, gators don't bask on the bank, as cold air can be colder than the water. Instead of hanging out in their burrows, where they might become trapped underwater if the water freezes over, alligators often swim to the surface to go snorkeling, ensuring that they'll have enough oxygen. 

If the water is cold, but not yet frozen, alligators will often swim to deeper waters, which are warmer than the shallows, Donnell said.

Unfortunately, not all of the alligators survived the cold snap at the Red Slough Wildlife Management Area, a 5,800-acre (2,300 hectares) refuge in southeastern Oklahoma that's managed by the Oklahoma Department of Wildlife Conservation, U.S. Forest Service and the Natural Resources Conservation Service. 

Donnell didn't immediately know how many alligators had died during the cold snap, but those that did were young. "Most of the adults were able to survive the cold-weather event," she said. "It's always fascinating how animals will adapt and how they can bring out different survival techniques."

Freezing temperatures and icy conditions aren't uncommon in southeastern Oklahoma; on average, McCurtain County, where Red Slough is located, has about 60 days a year with temperatures below 32 degrees Fahrenheit (0 degrees Celsius), according to a 2017 study in the journal Herpetological Review. 

Nor are snorkeling alligators unique to Oklahoma; they've also been spotted in North Carolina in 2018 and 2019, Live Science previously reported. 

Originally published on Live Science.

Human remains have been found inside the stomach of a 14-foot-long (4.2 meters) crocodile on an island north of Queensland, Australia. According to local authorities, the remains likely belong to Andrew Heard, a 69-year-old fisherman who went missing from the area on Feb. 11.

Heard was last seen that Thursday afternoon when he left his yacht on Hinchinbrook Island (close to the coast of northeastern Australia) in a small fishing dinghy, according to the Australian Broadcasting Corporation (ABC) news site. When he failed to return that night and stopped responding on his radio, Heard's wife called the authorities.

His dinghy was found capsized early Friday morning (Feb. 12), showing damage indicative of a crocodile attack.

On Friday night, investigators discovered human remains in the area; the next day, they found the gigantic croc nearby, according to the Queensland government. Environmental authorities euthanized the croc and cut it open, revealing more human remains in its guts.

"The crocodile captured yesterday is believed to be the animal involved in the disappearance of a man," Queensland Environment, a local government agency, tweeted on Saturday (Feb. 13). "Our thoughts are with the family at this difficult time."

The coasts around Queensland are home to the largest species of crocodile on Earth: the saltwater crocodile (Crocodylus porosus). Saltwater crocs can grow up to 23 feet (7 m) long, though they rarely exceed 16 feet (5 m), according to the Queensland Museum. They inhabit coastal waters throughout the western Pacific, from the southern coast of India to northern Australia. And they are known to attack humans.

Indeed, two additional crocodile attacks were reported in Queensland in the last two weeks, according to Vice News. In late January, a man in his 40s was bitten on the head while swimming at Lake Placid, roughly 100 miles (160 kilometers) north of Hinchinbrook Island. The man survived with minor injuries after prying the croc's jaws open with his hands, according to news reports.

Several days later, a 22-year-old man was attacked by a 12-foot-long (3.6 m) crocodile while swimming near Australia's northernmost tip. He survived with lacerations to his hand, and the croc was subsequently euthanized.

Originally published on Live Science.

A monster croc spanning 16 feet (5 meters) ruled the waterways of south-eastern Queensland in Australia millions of years ago.

Researchers from the University of Queensland identified the reptilian giant — now dubbed “swamp king" — after studying its fossilized 25-inch-long (65 centimeters) skull, which was first uncovered in the 1980s. 

In Latin, the genus name Paludirex translates to “swamp king” and the species name vincenti was chosen to honor the late Geoff Vincent, a resident of the town of Dalby in south-eastern Queensland who discovered the giant skull near the town of Chinchilla in Queensland.

Related: What's the world's largest crocodile?

The largest modern-day crocodile is the Indo-Pacific saltwater crocodile (Crocodylus porosus), which can grow to around the same size. Their record size is actually even larger at over 20 feet (6 m), set by Lolong who died in captivity in the Philippines in 2013, according to CNN.

"But Paludirex had a broader, more heavy-set skull, so it would've resembled an Indo-Pacific crocodile on steroids," Jorgo Ristevski, a doctoral candidate at the University of Queensland’s School of Biological Sciences, said in a statement. According to the researchers, this would have allowed the giant croc to hunt oversized prehistoric marsupials and made it one of the top predators in Australia. 

The swamp king likely emerged around the same time as modern-day crocs — within the last 55 million years. More research is now being carried out to determine how these massive crocs died out, while their slimmer relatives remained.

“Whether Paludirex vincenti went extinct as a result of competition with species like Crocodylus porosus is hard to say,” Steve Salisbury, a senior lecturer at the University of Queensland and fellow author of the study, said in the statement. "The alternative is that it went extinct as the climate dried, and the river systems it once inhabited contracted,” he explained, adding, “we're currently investigating both scenarios."  

The findings were published Dec. 21 in the journal PeerJ.

Originally published on Live Science.

Cornered by a dangerous predator, a gecko can self-amputate its still twitching tail, creating a fleeting moment of distraction - a chance for the lizard to flee with its life.

Small reptiles such as geckos and skinks are well known for this remarkable ability to sacrifice and then rapidly regrow their tails. Now, to scientists' surprise, it turns out that much larger alligators can regrow theirs too. But only while they're young.

Juvenile American alligators (Alligator mississippiensis) can regrow up to 18 percent of their total body length back. This is about 23 cm or 9 inches of length.

What's really cool is this regrowth appears to occur via a mechanism we've not seen before.

By imaging and dissecting the tail regrowth, researchers from Arizona State University (ASU) found alligators do this quite differently from the other animals we know that can regenerate their appendages.

As far as regrowing body parts goes, amphibious axolotls are the champions of regeneration amongst land animals with internal skeletons.

If injured, they can reform a segmented skeleton, complete with muscles that differ along their height - distinguishing top from bottom. 

Regrown lizard tails do not have a segmented skeleton, but lizards do reform muscles - although they look uniformly the same, with no variation in topside structure compared to the bottom.

This may be because regenerating appendages is physiologically expensive, and in smaller lizards has been shown to reduce overall growth rate.

Alligators, it seems, don't even bother re-growing muscles at all.

"Clearly there is a high cost to producing new muscle," said ASU animal physiologist Jeanne Wilson-Rawls. 

The team believes that even a muscle-less extra bit of tail must give these dangerous predators an edge in their murkily watered homes.

Unlike lizards, they can't self-amputate - their tail loss usually results from trauma inflicted by territorial aggression, or cannibalism from larger individuals.

Damage from human interactions, like motor blade damage have also been recorded.

The connective-tissue alligators replace skeletal muscle with is more like the wound repair you would see in the tuatara or in mammal wound healing, the team explains. 

"The regrown alligator tail is supported by an unsegmented cartilage tube rather than bone... lacked skeletal muscle and featured scar-like connective tissue populated with nerves and blood vessels," ASU cellular biologist and first author of the research Cindy Xu explained on Twitter.  

"Regrown tails from juvenile American alligators exhibit features of both regeneration and wound repair." 

But regrowth of cartilage, blood vessels, nerves and scales is similar to what is seen in lizards.

"Future comparative studies will be important to understand why regenerative capacity is variable among different reptile and animal groups," said Xu.

It also may take them considerably longer to regrow their missing bits. While skinks can do it in as little as six months, a related crocodilian, the black caiman (Melanosuchus niger) takes up to 18 months to reform their tails.

Alligators are an ancient lineage of reptiles, who shared a common ancestor with birds around 245 million years ago, back when non-avian dinosaurs dominated the Earth.

There's fossil evidence of an ancient crocodilian from the Jurassic period that also had a regenerated tail.

This "raises the question of when during evolution this ability was lost. Are there fossils out there of dinosaurs, whose lineage led to modern birds, with regrown tails?" ASU biomedical scientist Kenro Kusumi questions. 

"We haven't found any evidence of that so far in the published literature."

The team notes so far they've only been able to observe the end product of tail regenerations in alligators.

Given that they are a threatened species, further studies on how this process works may be challenging, but could provide some useful information.

"If we understand how different animals are able to repair and regenerate tissues, this knowledge can then be leveraged to develop medical therapies," said ASU anatomist Rebecca Fisher.

This research was published in Scientific Reports.

This article was originally published by ScienceAlert. Read the original article here.

Picking the kids up from school takes on a different meaning for crocodylian parents.

In this photo, taken by India-based photographer Dhritiman Mukherjee, a male freshwater gharial shows us why. Bobbing in the waters of northern India's National Chambal Sanctuary, the croc waits as more than 100 of his month-old children clamber onto his back for safe passage.

"Other crocs carry their young about in their mouths," Patrick Campbell, the senior curator of reptiles at London's Natural History Museum, told BBC.com. "But for the gharial, the unusual morphology of the snout means this is not possible. So the young have to cling to the head and back for that close connection and protection."

Related: 20 Amazing animal tongues

Gharials can measure up to 15 feet (4.5 meters) long and weigh more than 2,000 lbss. (900 kilograms). They are named for the bulbous nobs that males sport on the ends of their snouts. (These nobs are called gharas, which is the Hindi word for "mud pot," according to National Geographic). Crocs use their gharas to amplify vocalizations and blow bubbles during mating season — an adaptation that seems to have served this particular croc well. According to Mukherjee, the pictured papa mated with seven or eight different females to achieve this brood of 100-plus hatchlings.

Hopefully, all those kids grow into healthy adults and become parents themselves. Gharials are critically endangered, with an estimated 650 adults left in the freshwaters of India and Nepal, according to the Natural History Museum. India’s National Chambal Sanctuary, which Mukherjee patrolled for weeks to get this shot, contains 500 of those full-grown gharials.

Mukherjee's photo is one of 100 "highly commended" images in this year's Wildlife Photographer of the Year competition, hosted by the Natural History Museum of London. Chosen from more than 50,000 entries, the image will join 99 others on the museum's walls and eventually in a traveling exhibition, after the overall winners are announced on Oct. 13.

One of last year's winning entries showcased two subway mice in a desperate struggle over a scrap of snack food. Does Mukherjee's Gharial Father of The Year have what it takes to dethrone them? Check back in October to find out.

Originally published on Live Science.

A hefty, 10-foot-long (3 meters) crocodile relative had an odd way of getting around 120 million years ago in what is now South Korea. The huge beast walked on its two hind legs like a T. rex, researchers said after analyzing footprints left behind by the reptile. 

There are no known fossilized bones of this strange crocodile, but dozens of its up to 120 million year-old footprints, including one with skin impressions, are preserved in stone.

"For the first time, we have proof that some of the giant crocodiles of the Cretaceous were bipedal and really designed like the carnivorous dinosaurs," study co-researcher Martin Lockley, professor emeritus of geology at the University of Colorado Denver, told Live Science.

Related: Photos: Dinosaur tracks reveal Australia's 'Jurassic Park'

Researchers found the fossilized footprints ahead of a construction project. Researchers named it the Sacheon Jahye-ri tracksite, as it's west of Sacheon City in South Gyeongsang Province.

The track marks are big, up to 9.5 inches (24 centimeters) long, the researchers said. The crocodile also likely "had legs about the same height as human adult legs," study senior researcher Anthony Romilio, a paleontologist at the University of Queensland in Australia, said in a statement. 

After Korean researchers transferred the trackways to a lab, they invited Lockley to look at the impressions in November 2019. Initially, the team thought that these prints might belong to a giant pterosaur, but the instant Lockley saw them, he said he knew they were from a crocodile relative. 

Previously, Lockley had studied crocodile prints from the Jurassic period (199 million to 145 million years ago). The crocodile that left those prints was much smaller — its tracks were about 1 inch, or 2.5 centimeters long — and it walked on all fours. Even so, those prints were remarkably similar to the newly discovered ones, he said.

This realization triggered another memory; Lockley and his colleagues had published a study in 2012 in the journal Ichnos on what they thought were giant pterosaur tracks from the Cretaceous period of Korea. At the time, however, they knew something was weird about the tracks, so they called them "enigmatic." Looking back, Lockley realized that just like the newfound tracks, the enigmatic prints are most likely from a two-legged crocodile. 

Working together, the team found myriad clues that the newfound trackway belonged to a crocodile and not a pterosaur. For example, pterosaurs likely used their wings while walking, meaning they walked on all fours. But no handprints (or wing prints, for that matter) were found. In addition, the skin impression found on a heel print resembled that of a crocodile, Lockley said. Moreover, the prints had robust digits and impressions of pads and joints that looked just like those from a crocodile, he said.

That said, it's understandable that the researchers initially thought these trackways belonged to giant pterosaurs. "Typical crocodiles walk in a squat stance and create trackways that are wide," study lead researcher Kyung Soo Kim, a paleoecologist at the Chinju National University of Education in South Korea, said in the statement. "Oddly, our trackways are very narrow looking — more like a crocodile balancing on a tight-rope." 

"When [the footprints were] combined with the lack of any tail-drag marks, it became clear that these creatures were moving bipedally," Kim said. 

The team named the newfound fossil prints Batrachopus grandis. (Trace fossils, such as fossilized trackways and burrows, are given scientific names, just as animals are.) 

During the lower Cretaceous, the track site was a lake surrounded by muddy ground, "which made for making good tracks," Lockley told Live Science. It's difficult to say how these prints were preserved, but perhaps the creature left the prints in wet mud just before the lake retreated, allowing the prints to dry and harden. When the water level rose again, mud and fine silt could have covered and preserved the tracks, Lockley said.

Or, maybe the mud was soft and soupy, like warm ice cream, but the ground under the "ice cream" was hard, he said. The crocodile could have squished through the muck and left an impression on the hard ground underneath, which would have been instantly buried and preserved by the "ice cream" when the animal lifted up its foot, Lockley said. 

The study was published online yesterday (June 11) in the journal Scientific Reports. 

• Photos: Giant long-necked dinosaurs walked on water
• Photos: Analyzing an Amazing, Amphibious Dinosaur
• Photos: Dinosaurs sloshed around ancient lagoon

Originally published on Live Science.

Once upon a research grant, scientists strapped three dead alligators into weighted harnesses and deposited the corpses 6,600 feet (2 kilometers) down in the Gulf of Mexico. 

The first gator was overrun with giant pink crustaceans within a day and slowly eaten from the inside out. 

The second gator was devoured down to its skull and spine after 51 days. 

And the third gator? Well, nobody knows; its corpse was ripped from the harness and carried off by an unseen predator within a week, leaving behind some torn rope and unsettled sand.

This is either the least-satisfying fairytale ever, or the results of a strange new marine-food-cycle study described in the journal PLOS ONE. (Answer: It's both.)

Related: Beastly Feasts: Amazing Photos of Animals and Their Prey

The authors of the study (published Dec. 20) set out to test how carbon-hungry creatures of the deep, dark ocean would react to a food source they'd never seen before — namely, the scaly carcass of a freshwater gator (Alligator mississippiensis). 

Denizens of the deep ocean can't afford to be picky eaters; it's too dark and cold down there for plants to undergo photosynthesis, and nutrients are scarce. 

"The deep ocean is a food desert, sprinkled with food oases," study co-author Clifton Nunnally, of the Louisiana Universities Marine Consortium, said in a video about the experiment, released last April. "Some of these oases are vents in the ocean floor where chemicals come out or food falling from the ocean's surface."

Research into these "food falls" has mostly focused on large mammals, like whales, whose corpses provide a blubbery banquet for sea creatures large and small. While freshwater gator corpses can be cast into the ocean by hurricanes and other adverse weather, the ecological aftermath of such a "gator fall" has never been observed before now. Could the worms, crustaceans and other residents of the ocean floor find a way to penetrate the gators' thick hides and liberate the tasty meat within? The researchers didn't think it likely — however, they were quickly proven wrong.

When the team sent a camera-wielding robot to check on the first gator one day after laying it to rest at the bottom of the Gulf, they found the corpse being picked apart by huge, pill-bug-like isopods (Bathynomus giganteus) — some of which had already burrowed inside the gator and begun eating it from the inside. These crustaceans, the researchers noted, can store the energy from a single meal for months or years at a time, meaning that the hungry buggies scavenging the dead gator wouldn't have to work for more food for quite some time.

The second gator fared even worse. When the researchers revisited the corpse 51 days after deployment, it was picked clean, down to the bones. Those bones were caked in a mysterious brown fuzz, which a DNA analysis revealed to be a newly discovered species of bone-eating worm (genus: Osedax). This is the first time any Osedax species has been detected in the Gulf of Mexico, the researchers noted.

The final gator corpse disappeared from its harness before the researchers could spot any marine creatures eating it, but it's clear that the gator didn't wake up and swim away on its own. Considering that the creature and the harness weighed a combined 80 pounds (36 kilograms), it would have taken a large predator to chomp through the rope and haul the carcass away. A shark is the likeliest culprit, the researchers hypothesized.

So, to conclude the tale of “The Gators Who Fell Into the Sea,” many a bottom-feeding marine creature slaked its appetite on the tasty reptilian flesh — including some brown, bone-eating worms that nobody knew existed. And they all lived happily ever after, until their corpses were devoured in kind. The End.

• Photos: The Freakiest-Looking Fish
• Photos: Deep-Sea Expedition Discovers Metropolis of Octopuses
• Marine Marvels: Spectacular Photos of Sea Creatures

Originally published on Live Science.

Hundreds of crocodiles make their home in a network of canals in southern Florida. These channels also happen to carry water that cools a nearby nuclear power plant.

But don't worry — these crocodiles aren't mutants, monstrous or radioactive. In fact, the reptiles are thriving in these waters. American crocodiles (Crocodylus acutus) were formerly edging toward extinction, but their numbers have multiplied enough to elevate their federal status from "endangered" to "threatened" in 2007.

And scientists want to keep it that way. A team of experts with the Florida Power & Light (FPL) recently collected 73 crocodile hatchlings from canals near the FPL Turkey Point Nuclear Generating Station, located near Biscayne National Park. Biologists will implant the baby crocs with microchips, to help researchers continue monitoring the health of the croc colony, the Associated Press (AP) reported. [Alligators vs. Crocodiles: Photos Reveal Who's Who]

Several hundred crocodiles now inhabit Turkey Point canals, CBS Miami reported. To ensure the crocodile population's continued growth and success, FPL biologists visit the canals every year between January and April to build nesting sites for crocodile mothers. Months later, hatchlings are caught, measured and microchipped, and then are redistributed among the canal network — which spans 168 miles (270 kilometers) — which offers the babies a better chance of survival than being released together in the same spot, according to the AP.

Since the conservation and monitoring program began, the "Croc Team" has tagged more than 7,000 crocodiles, FPL representatives reported. In addition to microchipping hatchlings, scientists also construct ponds to protect the young from predators, and conduct surveys to track the health and growth of the canal-dwelling crocodiles, according to FPL.

Saved by canals

American crocodiles are native to southern Florida, which is the northernmost part of their range; they are also found in coastal regions in South and Central America, and in the Caribbean Sea. These reptiles can grow to be 20 feet (6 meters) long and weigh more than 2,000 lbs. (907 kilograms), though individuals in U.S. breeding populations tend to be somewhat smaller than that, according to the U.S. Fish and Wildlife Service (FWS).

Human activity destroyed much of the crocodiles' estuary habitats during the early part of the 20th century, causing their decline. The FWS classified the species as endangered in 1975, but construction of the Turkey Point canals brought an unexpected reprieve to the beleaguered reptiles.

The project created berms — elevated strips of land bordering the canals. This inadvertently provided the animals with a new nesting habitat, and the species began to recover, researchers with the University of Florida reported in a 2006 conference presentation.

Females typically lay between 20 and 60 eggs, but few of them grow to be adults: Most of the defenseless hatchlings are eaten by fish, gulls, wading birds and crabs, the FWS says. Fortunately for the Turkey Point crocodiles, one predator they don't have to worry about at this location is people, as the site is remote enough to protect the crocodiles from human hunters, the AP reported.

But how safe is the water in those cooling canals? In March, the Nuclear Regulatory Commission’s Atomic Safety and Licensing Board said that it would hear arguments over whether these canals — which contain ammonia — could harm the nesting crocodiles or other threatened and endangered animals, according to a report in the Miami Herald.

The waterways also seem to have elevated levels of tritium, a radioactive isotope of hydrogen, which could be leaking into the adjacent Biscayne Bay, according to a study released by the Miami-Dade County Mayor Carlos Gimenez in 2016, as reported by the Miami Herald.

• Photos: 'Giant Crocodile' Egyptian Mummy Is Packed With Baby Crocs
• Photos: Ancient Crocodile Relatives Roamed the Amazon
• Beastly Feasts: Amazing Photos of Animals and Their Prey

Originally published on Live Science.

A 12-foot-long (3.7 meters) alligator weighing a lumbering 463 lbs. (210 kilograms) was lying on its back in the middle of a highway exit when trapper Broderick Vaughan showed up in the early morning of June 3.

Vaughan, there in his capacity as a contractor for the Florida Fish and Wildlife Commission, said police patrol cars were parked on either side of the Interstate 10 exit in Tallahassee when he arrived, keeping traffic away from the massive creature. It had a large wound on the side of its head and snout, and police told Vaughan that the animal had been wandering in circles for a long time before he showed up. But by the time he got there, the reptile was still.

"I thought it was dead," Vaughan told Live Science. [What to Do If You Come Face to Face with an Alligator]

Alligators expend their energy in bursts, and Vaughan said it's typical for one of his charges to exhaust itself during the process of capture, then sit very still for hours. In this case, the injured creature was already exhausted when Vaughan slipped a snare around its neck and taped its mouth shut. However, he said, on the way home, it "came back to life."

Police determined from debris in the area that the creature sustained its wound in a collision with a semitruck, according to Vaughan. The driver, once tracked down, said he thought he'd missed the creature, police told Vaughan. Vaughan speculated that the alligator lifted its head up at the last moment and struck a "bolt" or some other protrusion from the vehicle.

Its injury was serious enough that Vaughan decided to euthanize the animal; Vaughan is forbidden from releasing alligators of this size back into the wild, and instead must either euthanize them or turn them over to farms or exhibits.

This was the third largest alligator Vaughan had ever encountered, he said. The largest was 12 feet, 8 inches (3.86 meters) long. Florida, which has a population of 1.3 million alligators across all 67 of the state's counties, considers any alligator over 4 feet (1.2 meters) long a "nuisance" and forbids relocating those captured individuals into the wild.

• Alligators vs. Crocodiles: Photos Reveal Who's Who
• Alligator Alley: Pictures of Monster Reptiles
• Crocodiles: Ancient Predators in a Modern World (Photos)

Originally published on Live Science.

In a creepy video fit for a scene in a horror movie, nightmarish "bugs" that almost look like lobsters emerge on the seafloor to attack the corpse of an alligator, using their mandibles to break through the scaly skin and feed on the juicy insides.

The carcass is lying a mile and a quarter (2 kilometers) down on the bottom of the Gulf of Mexico, and the football-size isopods — they are related to roly polies or pill bugs — are having a field day. These isopods may go for months or years between meals, according to researchers Craig McClain and Clifton Nunnally, both of the Louisiana Universities Marine Consortium. [Beastly Feasts: Amazing Photos of Animals and Their Prey]

"They have this amazing ability to gorge themselves, store that energy and then basically not have another meal for months to years afterwards," McClain said in the video.

Gator fall

The alligator came to its watery grave courtesy of McClain, Nunnally and their colleagues, who are interested in studying how "foodfalls" impact marine ecosystems. Foodfalls can be anything from a giant whale carcass to logs of wood (certain clams and specialized bacteria can digest wood) washed into the ocean via rivers. Alligator carcasses may be a common type of foodfall, McClain said, but no one has ever studied them before.

The researchers weighted the carcasses of alligators donated by the state of Louisiana, which humanely euthanized the animals as part of its alligator management program. They then watched on-camera what creatures came to feast.

"The deep ocean is a food desert, sprinkled with food oases," Nunnally said in the video. The gator carcass is a particularly interesting oasis, he added, because alligators are the closest thing alive today to ancient marine reptiles like ichthyosaurs. Some of the creatures that feed on modern alligators could be the same that ate ichthyosaurs millions of years ago, he said.

Easy work

Isopods are crustaceans with ancestors dating back 300 million years. The giant isopods feeding on the alligator seemed well-adapted to their role as scavengers. In less than 24 hours, several were immersed halfway into the alligators' abdomen, chowing down from the inside.

"I thought the alligator hide would be something that would be hard to get through, but obviously their pinching and crushing mandibles make easy work of the hide," Nunnally said.

One isopod in the video starts to swim away, only to take a nosedive directly into the sandy seafloor. The animal might be so stuffed with its rare meal that it has trouble moving, the researchers said. [In Photos: Spooky Deep-Sea Creatures]

"We've seen that in other scavengers, where they'll eat so much that they basically become immobile or stupefied in their actions, and so that may just be the fact that they've gorged themselves so much in an effort to get this rare resource that they've actually, you know, inhibited themselves from proper locomotion," Nunnally said in the video.

The project also aims to understand how carbon from land-based life-forms reaches the deep ocean. The researchers set the alligator carcass down nearly two months ago and plan to return to the site later this week. They expect that the carcass will be half gone, and that other scavengers will have moved in to get flesh that the isopods couldn't reach. It's even possible that bone-eating worms called osedax might be found in the gator's skeleton.

"I think it will be interesting to see what new scavengers show up," Nunnally said.

Between April 10 and April 24, the researchers will be tweeting about their discoveries at @LUMCONscience, @DrCraigMc and @seagrifo using the hashtag #woodfall.

• Photos: The Freakiest-Looking Fish
• Photos: Deep-Sea Expedition Discovers Metropolis of Octopuses
• Marine Marvels: Spectacular Photos of Sea Creatures

Originally published on Live Science.

Natalia Rossi is the manager of the Cuba Program for the Wildlife Conservation Society (WCS). This article is part of Women's History Month, and celebrates women in science. Rossi contributed this article to Live Science's Expert Voices: Op-Ed & Insights.

I, a crocodile scientist, am a woman in conservation. As is my colleague Christelle Nguizi, who tirelessly patrols the flooded forests of the Lac Tele Community Reserve in Congo to protect elephants and combat poachers; and my colleague Lilian Painter, who directs the Wildlife Conservation Society's Bolivia Program and — working with partners — secured the protection of 2.3 million hectares (5.6 million acres), the most biodiverse region for plants and animals in the entire world.

My colleague Emily Darling takes coral reef conservation science to a completely new level by linking social and ecological systems to make reefs and coastal communities more resilient. And there are so many others. We are all women in conservation. From every possible angle, we are working to conserve the world's precious biodiversity. We are re-shaping the field and we are not afraid of tackling new challenges. [Photos: 'Giant Crocodile' Egyptian Mummy Is Packed With Baby Crocs]

But the path here is not always easy. Despite women's rising numbers in this field, the majority of people in senior positions in conservation worldwide continue to be men. Challenges often begin the moment a woman enters the profession. (For instance, people may ask whether you are capable of withstanding the harsh field conditions that "men do." But I would rephrase that question to ask whether people can withstand the harsh field conditions that women do, as we are hardcore.) As women climb the ranks, these challenges can continue, as your voice is sometimes the only woman's voice in the room. Even in the field, perceptions toward the types of roles and jobs of women are expected to hold may not match your outfit. But a new wave of women scientists is entering the field of conservation, and we are working from the field to the policy-level to address these problems and change attitudes.

I am so immensely proud of my female colleagues. But reaching these heights was not easy. At least for me. Adjusting to a new country when I first arrived from Argentina to pursue my dream of studying conservation biology was a tough initial hurdle. Then there were times in the field when being a woman encompassed additional difficulties and even risks.

That comes with being a crocodile specialist, of course. You can only imagine the "toughness" that you have to show when getting involved in crocodile conservation, a still male-dominated field. When you jump into muddy waters full of crocodiles and all male eyes are on you, and you feel the silent wonder: Is she going to make it? I imagine that same scrutiny was imposed on so many of the women conservationists of my generation and before.

But I do this work because I see so clearly that the interconnection between species, habitats and the health of ecosystems is critical to local communities and our planet as a whole. Where I work in Cuba, two native crocodile species are found: the critically endangered Cuban crocodile and the vulnerable coastal American crocodile. These top predators are not only critical for keeping the food chain in check but also true ecosystem engineers that shape and help maintain mangrove forests through excavating massive underwater caves and canals, which create water dynamics and essential micro-habitats that support a rich diversity of species. The threat of development of the country's coastal areas, along with historical poaching and a restricted range for the Cuban crocodile, jeopardize the survival of both crocodiles and mangroves. For almost a decade, we have been working alongside local partners to better understand crocodiles and design strategies to strengthen their populations. From reintroduction of crocodiles in the wild, to the provisioning of additional nesting sites, to community involvement and outreach, we have been growing our efforts to save crocodile species for future generations.

Mentorship matters

For so many women across the world, it is still a dream to enter this field, in part because of the pre-conceptions on what women can and can't do on the job. For instance, some may wonder whether women can take on the physical tasks of handling wild animals. Nevertheless, to these women I say things are changing! It is possible! Conservation needs your vision, ideas and strength more than ever. Communication channels between women conservationists are wide open, and there is nothing more powerful than mentorship and sharing.

In my case, I have also been blessed with wonderful mentors who were men, including the late John Thorbjarnarson (1957-2010), a world-renowned herpetologist who helped to rescue numerous species from the brink of extinction. John T, as we called him, saw something in me that I could not see at the time. His encouragement, passion and sense of humor made my firsts steps working in Cuba to protect crocodiles and coastal wetlands feel effortless. [Photos: Ancient Crocodile Relatives Roamed the Amazon]

I am happy to continue in the footsteps of Thorbjarnarson and my amazing colleagues in Cuba. Using our passion every day to help species, ecosystems and communities thrive gives us a sense of purpose and brings us together. But I truly believe that the strides made by women in the field of conservation will be meaningful only if these achievements by conservation role-models and leaders open up a path for the next generation of young women scientists. Such a path would include more opportunities for matching young female conservationists with mentors, and more concrete avenues that provide that precious "first opportunity" in conservation for aspiring women.

I have no doubt this a new wave of women will bring creative solutions to conservation challenges in ways we cannot even imagine today.

I had a taste of that at the "The Girls Advancing in STEM Conference" last year. There, 100 high school girls from around the United States gathered to learn about science, technology, engineering and math, the STEM fields. Through mentorship and establishing connections, we can not only let others know about our work but, most importantly, unleash so much potential as a community of women conservationists in the world. Together, we can advance to all levels of leadership and responsibility.

One thing is clearer than ever to me today. These are exciting times to be a woman (and a man) in conservation!

• In Photos: Response Teams Try To Save Starving Killer Whale
• In Photos: Mexico's New Ocean Reserve Protects Stunning Biodiversity
• In Photos: Giant Owls and Painted Snails: Incredible Creatures from Cuba

The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on Live Science.

Editor's Note: This article was updated to indicate that the Girls Advancing in STEM Conference took place in the United States, not in Cuba.

As temperatures dipped along the U.S. East Coast, alligators at a sanctuary park in North Carolina figured out a cute way to survive in their icy homes: They poked their noses out of the water as it began to freeze over, their scaly "snorkels" becoming their only conduit for oxygen.

Several American alligators were spotted this week with their noses breaching the icy water's surface at The Swamp Park in Ocean Isle Beach, in southern North Carolina, which houses rescued alligators in a fenced-off body of water near the Shallotte River.

"The water they are in does tend to freeze on consecutive sub-freezing nights. This does not happen often," said George Howard, the park's general manager. "They do this as a survival technique — a coping mechanism to allow them to breathe in the event the water freezes over." [Alligators vs. Crocodiles: Photos Reveal Who's Who]

Howard spotted the same nose-poking behavior last January at the park during the so-called bomb cyclone.

"This time of year, they are in a process called 'brumation,' kind of like hibernation except they are fully aware," Howard told Live Science. "They lower their metabolism to survive the cold. They don't eat for a few months, until the temps get up to 70 [degrees Fahrenheit; 21 degrees Celsius] and above."

During brumation, an alligator's metabolism slows down, allowing the reptile to go without food and just "chill" for four to five months.

They can't let their bodies get too cold, however, or they will die. American alligators (Alligator mississippiensis), a member of the order Crocodilia, are cold-blooded animals, so they essentially take on the temperature of their surroundings. That's why they bask in the sun, using the heat to get toasty, and why they can't live too far north in the U.S.

When air temperatures drop below about 70 F, the reptiles sometimes dig out muddy underwater dens to keep warm. They can also apparently stay submerged in water with only their snouts sticking above the surface for hours to a few days, said Greg Skupien, of the North Carolina Museum of Natural Sciences, who cited research published in the 1980s.

In a study published in 1982 in The American Midland Naturalist, researchers from the Savannah River Ecology Laboratory found that an alligator in an iced-over pond in South Carolina kept a breathing hole in the 0.6-inch-thick (1.5 centimeters) ice for several days, though the animal later died because its body got too cold, dropping to 39 F (4 C).

Scientists reported on a similar behavior in 1983 in the Journal of Herpetology, describing a "'submerged breathing' posture in which the snout broke the water (i.e., ice) surface, while the remainder of the head and the body angled back down into the den."

Though Skupien, curator of the Naturalist Center at the museum, has never witnessed the so-called icing response, he told Live Science that the behavior is "as weird as it gets for alligators."

He added, "There are other reptiles and amphibians that exhibit some pretty cool overwintering strategies, such as frogs that produce cryoprotectants (i.e., antifreeze) and turtles that can essentially breathe from their butts (i.e., cloacal respiration)."

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• Crocs: Ancient Predators in a Modern World (Photos)

Originally published on Live Science.