On Christmas Day 2024, tragedy struck Yellowstone's Junction Butte wolf pack. The group's legendary one-eyed leader, Wolf 907F, died after a confrontation with a rival pack. Now, in a new video, Junction Butte is hunting bison with members of that rival pack — albeit unsuccessfully.

Julie Argyle, a wildlife photographer and conservationist, filmed the Junction Butte gray wolves (Canis lupus) chasing two bison (Bison bison) as they attempted to separate a yearling calf from its mother, Cowboy State Daily reported.

The mother kept her body between the calf and the hungry wolves until the pair caught up with the rest of the group. Another adult bison then helped the mother fight off the wolves, ending the attempted hunt.

The video suggests that the Junction Butte wolf pack is back to full strength after losing Wolf 907F — thanks to some of the wolves that helped kill her.

Related: Reintroducing wolves to Yellowstone helped entire ecosystem thrive, 20-year study finds

The Junction Butte wolf pack made headlines under the enduring leadership of Wolf 907F. The "Queen of the Wolves" gave birth to a record-breaking 10 litters of pups and survived more than twice as long as most Yellowstone wolves — more than 11 years, compared with the average lifespan of up to five years.

Wolf 907F's demise began on Dec. 22, 2024. The rival Rescue Creek pack set upon Wolf 907F and some of her pack — it was split at the time — while they fed on a bison carcass on the north side of the Yellowstone River. The Rescue Creek pack began as an offshoot of the Junction Butte pack and normally stayed south of the river. But this time, they opted to cross and attack Junction Butte. Wolves rarely die of old age in the wild, and in Yellowstone National Park, they're often killed in territorial clashes with other wolves.

"In a protected place like Yellowstone, their number-one cause of death is when two packs fight with each other," Kira Cassidy, a researcher at the Yellowstone Wolf Project, told Live Science last year, after Wolf 907F had her record-breaking 10th litter. "That accounts for about half of the mortality," she added.

Wolf 907F was badly injured in the skirmish with the Rescue Creek pack, and data from her radio collar suggest she died Dec. 25. Her death came not long after the pack briefly ventured outside the park, where people shot and killed two other members of her pack.

In January, researchers spotted some of the Rescue Creek pack males with some of the remaining Junction Butte pack females. At the time, Cassidy told National Park Explorer that wolf mating season begins in February and it was likely that some of the wolves would change packs to mate.

The pack seems to be thriving again with males from the Rescue Creek pack, Cowboy State Daily reported. The wolves may have failed to kill the bison in the video, but taking down a bison is no easy task. The video shows that adult bison can put up a fight and will fiercely defend themselves and their herd.

Bison in Yellowstone National Park spent over 100 years as two genetically distinct herds. But now they're roaming as one interbreeding population, a new study suggests.

Herds of wild bison (Bison bison) have meandered through Yellowstone's vibrant landscape since prehistoric times. Grazing freely in the expansive grasslands of the park, these are the last free-range bison in the United States.

Although these animals are now abundant in the national park, poaching pushed the local population near extinction by the turn of the 20th century. Park managers tried several methods to help conserve Yellowstone’s bison, halting poaching and even introducing a new herd to the region.

Thanks to conservation efforts, both the native herd and the introduced herd, which consisted of adults from Montana and Texas and calves from Yellowstone’s native herd, were able to thrive. Later genetic analyses showed that descendants of this introduced group remained genetically distinct from the native bison — until now.

In the past 20 years, Yellowstone's two bison subpopulations have become one large interbreeding herd, according to the new genetic study, published Sept. 13, 2024 in the Journal of Heredity.

"I think the kinds of questions that we ask about this population at Yellowstone can only be answered using genetic technology," study senior author Jim Derr, a professor at Texas A&M's College of Veterinary Medicine and Biomedical Sciences, told Live Science. "No observational information is going to help you because you don't know who's breeding with who."

To reveal the breeding dynamics of the droves of bison in Yellowstone, workers at the National Park Service (NPS) collected tissue samples biopsied from 282 individuals for analysis.

Closely analyzing the bison's genetic markers gave the researchers clues into their lineage and how the population has changed over time.

Comparing the genetic markers they found in Yellowstone's current bison population to those from samples taken in the early 2000s, the researchers concluded that the two groups roaming the land interbred frequently enough that they are no longer genetically distinct.

The exact cause of the change isn't clear, but the researchers say it was likely a gradual shift in behavior over the past 20 or more years. "Part of it is just the bison exploring different areas and figuring their way out and running into each other," study lead author Sam Stroupe, a postdoctoral research associate at Texas A&M University, told Live Science.

The researchers hope this new analysis will help with ongoing efforts to conserve and manage the herd at Yellowstone.

Staff at the national park have been managing the bison population as two groups since individuals were first brought in from out-of-state in 1907. Having only one herd to look after could make conservation and management of the species easier, the researchers said.

"I think everyone wants bison in Yellowstone National Park to be managed appropriately and to have good stewardship of that herd," Derr said. "Hopefully we can give them a little bit of insight with this genetic information."

An 11,000-year-old settlement in Canada is challenging the idea that early Indigenous people were nomadic. The newly uncovered village site of Âsowanânihk, which means "a place to cross" in the Cree language, is one of the oldest archaeological sites found on the continent and suggests that an organized society existed in central Canada far earlier than experts previously thought.

"This site is shaking up everything we thought we knew and could change the narrative of early Indigenous civilizations in North America," amateur archaeologist Dave Rondeau, who first identified the site in 2023, said in a Feb. 4 statement.

Evidence already recovered from Âsowanânihk, located in the Sturgeon Lake First Nation (SLFN) in central Saskatchewan, includes stone tools, firepits and bison bones, according to the statement. A very large firepit suggests that the site was used for a long period, or repeatedly for shorter periods, according to Glenn Stuart, an archaeologist at the University of Saskatchewan who is involved in the project. Such use indicates that the settlement was likely a long-term one, rather than a temporary hunting camp, where Indigenous hunters strategically harvested the extinct Bison antiquus.

Related: Ancient Indigenous lineage of Blackfoot Confederacy goes back 18,000 years to last ice age, DNA reveals

Charcoal from one of the hearths was radiocarbon-dated to about 10,700 years ago, Stuart told Live Science in an email. This means that people were living in the village just after the last ice age ended, when there was finally land suitable for plants to grow.

"This indicates that people arrived in this location as soon as it was habitable," Stuart said, "and then continually reoccupied the site for thousands of years. Ancestral First Nations have been living in the area west of [the city of] Prince Albert for as long as it has been possible to live in the area."

"This discovery is a powerful reminder that our ancestors were here, building, thriving, and shaping the land long before history books acknowledged us," SLFN Chief Christine Longjohn said in the statement. "This site speaks for us, proving that our roots run deep and unbroken," she said.

The site of Âsowanânihk is currently being studied by archaeologists, including Stuart, alongside the SLFN's Âsowanânihk Council, which includes Elders, Knowledge Keepers and educators. The council is also working with local stakeholders to protect the site, which was originally identified because it was eroding out of a riverbank and now faces potential destruction from logging activities in the area.

Name: Bison Licking Insect Bite

What it is: A figurine of a bison licking its flank

Where it is from: Abri de la Madeleine (Magdalene Shelter) in St Remèze, France

When it was made: Approximately 14,000 years ago

Related: Arthur's Stone: A 5,700-year-old monument in England linked to the legend of King Arthur

What it tells us about the past:

This prehistoric carving, discovered inside a cave in France, depicts a steppe wisent (Bison priscus), a now-extinct species of bison. It was crafted from a piece of reindeer antler that was previously used as a spear thrower for hunting, according to the Bradshaw Foundation. 

Despite its small size — roughly 4 inches (10.5 centimeters) wide — the figurine contains a wealth of meticulous details, including finely carved individual hairs across the animal's body and a pair of horns jutting from its head, giving the piece a lifelike quality.

Archaeologists attribute the artifact to the Magdalenian, a Paleolithic culture that existed in Europe between 23,000 and 14,000 years ago, during the last ice age. These people were known for their elaborate artworks, including charcoal cave paintings and engravings using stone and bone tools, according to the Natural History Museum in London.

Not only were they expert artisans, but the people behind the Magdalenian culture were also adept big-game hunters who focused on hunting horses and bison. Researchers think that because food was plentiful, members of the culture had enough leisure time to focus on other endeavors, including art.

The artifact is currently housed at the National Museum of Prehistory in Les Eyzies, France.

Scientists have introduced bison to the Russian Arctic to take on the role of extinct mammoths and help restore ancient ecosystems.

Twelve plains bison (Bison bison bison) have arrived at Ingilor Nature Park, a protected area covering more than 2.2 million acres (900,000 hectares) in the northern Yamal-Nenets Autonomous Area. The animals traveled 5,000 miles (8,000 kilometers) from a nursery in Denmark and disembarked from their long journey three weeks ago, according to a statement. Before they can discover their new home, however, the bison — also known as buffalos — must first complete a one-month quarantine.

"Buffalo can easily adapt to the Arctic because, historically, it is their natural habitat," the Yamal-Nenets Autonomous Area Department of Natural Resources and the Environment said in a separate statement. "They can take on the role of mammoths, which became extinct 11,000 years ago."

Steppe bison and woolly mammoths roamed the Russian Arctic during the late Pleistocene epoch (2.6 million to 11,700 years ago). Though a small population of disastrously damaged mammoths survived on an island off Alaska until about 4,000 years ago, most of these herbivores died out at the end of the ice age, when the climate became warmer and the grassy plains gave way to shrubs and trees.

Related: Woolly mammoths were seasonal sex fiends just like elephants, study finds

"The Pleistocene ecosystem was treeless and had quite thick soils," Mary Edwards, an emerita professor of physical geography at the University of Southampton in the U.K., told Live Science. "What you can see in geological sections of these kinds of landscapes is that, over time, they're storing soil carbon — it's frozen by the permafrost and it's basically a big carbon stack."

The animals that lumbered across these frigid plains contributed to shaping the landscape by grazing and recycling nutrients. "It's a nice cycle of animal dung fertilizing the ground and allowing the plants to grow," Edwards said. "The thought is that the animals maintained the ecosystem."

A 'very interesting idea'

Now, in a bid to restore this Pleistocene landscape and its ability to soak up carbon, scientists are introducing large herbivores, such as plains bison, to different parts of the Arctic.

Nikita Zimov, the director of a restoration project called Pleistocene Park in Yakutia, has been bringing bison over from Denmark since 2019. "For our rewilding efforts we are bringing to the Arctic animals which either lived here during the ice age or those who could live here in the modern climate," he told Live Science in an email.

This year, Zimov bought a herd of 24 bison, half of which he gave to Ingilor Nature Park in exchange for 14 musk oxen (Ovibos moschatus). These musk oxen almost went extinct in the early 1900s, and only a few scattered herds remain in the Russian Arctic, he said.

With the musk oxen now en route to Pleistocene Park, Zimov said he "aims to restore high productive grazing ecosystems in the Arctic, and through various ecological mechanisms mitigate climate change."

But Edwards is skeptical. Animals can transform ecosystems locally, she said, but the climate during the Pleistocene was probably more important in shaping the landscape. "It was too cold and too dry for trees and shrubs to grow, so you had grasses and different kinds of herbs covering the landscape," she said.

Today's climate is much warmer and wetter, meaning the ecosystem may not be suitable for large herbivores. "You have to change the landscape for them and create pastures," Edwards said.

But modifying the landscape could have unintended consequences. Thawing permafrost means there is more water in the soil, which shrubs and trees take up. "If you got rid of all the shrubs everything would get waterlogged," Edwards said, adding that this stagnant water could contribute to thaw and enhance the loss of carbon from soils.

However, introducing these animals to the Russian Arctic is "a very interesting idea," Edwards said. "There's definitely a window for the reintroduction of some of the big, lost animals of the Pleistocene."

Three people have been gored by bison in a single month at Yellowstone National Park, with the two most recent attacks coming just two days apart. Park officials warned visitors to be respectful of the enormous beasts' personal space, as approaching too close can provoke bison to charge. 

The most recent incident occurred on Wednesday (June 29), when a 71-year-old woman from Pennsylvania was gored by a bull bison near Storm Point at Yellowstone Lake. She received non-life threatening injuries and was taken to hospital, according to a National Park Service (NPS) statement. Just two days earlier, on June 27, another bull charged at a 34-year-old man from Colorado who was walking with his family on a boardwalk near the Giant Geyser at Old Faithful. The man sustained injuries to his arm and was also taken to hospital, according to an NPS statement. 

The first incident of the year occurred on May 31, when a 25-year-old woman from Ohio was attacked near a boardwalk at Black Sand Basin, just north of Old Faithful; she was gored and thrown 10 feet (3 meters) into the air, according to an NPS statement. She sustained a serious puncture wound and other minor injuries, although at the time it was mistakenly reported that she had died, according to Smithsonian Magazine.

American bison (Bison bison) are the largest land mammals in North America; males, or bulls, can grow up to 8.2 feet (2.5 m) tall at the shoulder and weigh up to 2,000 pounds (907 kilograms), and their horns can grow to a maximum length of 2 feet (0.6 m). Bison have large, protruding shoulder humps made of massive neck muscles that help the animals shovel a path through deep winter snow with their horns. The massive mammals are also extremely fast and can reach a top speed of 35 mph (56 km/h), which is around three times faster than a human can run, according to NPS. 

Related: Secrets of 'mystery sandwich' beneath Yellowstone revealed in new map 

Bison injure more visitors than any other animal in Yellowstone, including grizzly bears (Ursus arctos horribilis), and there is typically at least one incident every year, according to NPS. During attacks, bison commonly charge at people and gore them with their horns, before throwing them into the air with their powerful neck muscles, as seen in this video of an attack in 1992. But surprisingly, despite the animals' incredible strength and size, these attacks are rarely fatal and are likely just a warning shot from the animals. 

This is not the first time Yellowstone has experienced a period of increased attacks. Between May and July 2015, five people were injured by bison, according to a 2016 report by the CDC. The highest number of attacks occurred between 1983 and 1985 when 33 people were injured, the report stated. Frequently occurring bison attacks have also been documented in other parks, such as Antelope Island State Park in Utah, where one individual was involved in two separate attacks just three months apart in 2019. 

However, bison only attack people when they feel threatened, which most commonly happens when people approach closer than they should. The NPS warns people to stay at least 75 feet (23 m), or the length of a tennis court, away from bison, especially around campsites, roads, walkways and car parks where the animals may be more stressed. The three people who were recently attacked in Yellowstone, as well as family members or friends who were with them at the time, were much closer to the animals than the recommended limit when they were gored, according to the NPS.

A problem in recent years has been people trying to get closer to bison — and other wildlife — to take photographs for social media. In 2015, one person who was injured by a bison later admitted they were attempting to take a selfie with the bison that attacked them.

National parks across the U.S. have seen a significant increase in visitor numbers since the easing of restrictions from the COVID-19 pandemic, which has caused a number of issues. However, it is unclear if this can be linked to bison attacks. 

There were once millions of bison in America, but by the 20th century the animals were in danger of becoming completely extinct. In 1902, there were only around two dozen bison left in the park, after the U.S. Army spent decades exterminating bison in America, in an attempt to starve Native American tribes, according to NPS. But thanks to a massive conservation program, there are now 5,450 bison in the park, as of the summer of 2021, and around 30,000 wild bison across North America, according to NPS.

Today, the challenge for park officials is to manage the growing bison population. Bison are naturally free-roaming and often try to migrate across park boundaries, which can cause conflict with locals due to the destruction of property and transmission of diseases to livestock, particularly brucellosis — a bacterial disease that causes miscarriages in bison, cattle and deer. As a result, Yellowstone officials prevent the population from growing by relocating bison to other parks or by implementing small, controlled culls.

Originally published on Live Science.

A trail runner who was gored by a bison at Antelope Island State Park in Utah in June decided to test his luck. After fully recovering, on Friday (Sept. 27), Kyler Bourgeous brought a date back to the park to watch the sunset — instead, in an odd twist of fate, his date also found herself facing the horns of a bison, according to recent news reports. 

"I thought my situation was just a freak accident," Bourgeous told The Washington Post.

Was it just that, a freak accident? And why do these large but seemingly harmless bearded beasts, gore people?

"It's actually really uncommon," said Wendy Wilson, an assistant park manager at the Antelope Island State Park, which is home to around 700 bison. In the past decade, about 4 million people have visited the park, with just five bison incidents. So it's "unusual" that there were two serious attacks just this year that sent people to the hospital, she added.

Related: Beasts in Battle: 15 Amazing Animal Recruits in War

If they feel threatened, rather than actually attacking, bison are more likely to fake charge, Wilson told Live Science. "That being said, however, they can be aggressive," she said. Bison aren't predators — they're prey — and they will defend what they feel is a safe space, she added. "If we enter into that safe place, they're going to take measures to make themselves feel safe again." 

Bison become more aggressive during mating season between July and September, according to a CDC report from 2015. Since 1980, bison have injured more people in Yellowstone National Park than any other animal has. Most of those injuries happened because people got too close to the beasts, for instance to take photographs or selfies, according to the report.

But "these two cases really are kind of two situations where the folks were in the wrong place at the wrong time," Wilson said. In June, Bourgeous, a 30-year-old cyclist and trail runner, had climbed to the highest point in the park when he happened upon two adult bison; he scrambled to get out of their eyesight, according to The Washington Post. 

But he didn't escape the attention of one of the bison that charged at him — slamming into him with its horns with such force that it flung him into the air. Once he hit the ground, the bison trampled him and then waited to see if he'd move, Bourgeous told the Post. He was airlifted to the hospital, but was fine save for a cracked rib and collapsed lung.

Bourgeous and his date, 22-year-old Kayleigh Davis, went on a run last Friday at the same state park. While Bourgeous put on bug spray, Davis ran ahead of him, according to the Post. A little ways ahead, she saw a bison and quickly turned off the trail to give the animal room — but then some people rode by on bikes. 

There was "too much activity that made the bison uncomfortable," Wilson said. The animal ended up charging her, flinging her into the air. She was also airlifted to the hospital for injuries including a broken ankle and a wound on her thigh.

"In a situation like that, they both did what they could," she said. If you encounter a bison that close, you should try to back away as quickly as you can — if you can, turn around and go back the way you came, Wilson said. If you can't, or if you need to get past the bison to get to your car for example, try to go really far around it — maybe twice as far as what you think is safe, she said.

And you shouldn't try to outrun a bison, which can reach speeds of about 35 mph (56 km/h). And though they're the biggest mammals in North America, bison are agile, able to make quick turns and jump high fences, according to the U.S. Fish and Wildlife Service.

Davis is now recovering, perhaps having starred in the beginning of a wild love story.

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Originally published on Live Science.

Burly, shaggy bison (Bison bison), the North American hoofed mammals that, for many people, embody the American West, are often referred to as buffalo.

But even though they are in the same family group as Old World buffalo species — the Asian water buffalo (Bubalus bubalis) and the African cape buffalo (Syncerus caffer) — bison are not closely related to those species, making the common name "buffalo" misleading.

When the first European settlers arrived in North America, as many as 60 million bison inhabited the continent's grasslands, according to the U.S. Fish and Wildlife Service (USFWS). These early settlers likely saw similarities between bison, the continent's largest land animal, and known buffalo species, the National Park Service (NPS) explained on its website. The settlers referred to the large beasts as "bison" and "buffalo" interchangeably, and the name "buffalo," though scientifically inaccurate, stuck.

Related: What's the difference between Asian and African elephants?

The mistake is somewhat understandable. Both bison and buffalo belong to the Bovidae family, which consists of more than 100 species of hoofed mammals called ungulates, including buffalo, bison, antelopes, gazelles, cattle, sheep and goats. The American bison species is found only in North America, and its closest relative, the European bison (Bison bonasus), can be found in Belarus, Lithuania, Poland, Romania, Russian Federation, Slovakia, Ukraine and Kyrgyzstan, where about 1,800 free-ranging individual bison are currently estimated to roam, according to the International Union for Conservation of Nature.

Bison likely first arrived in North America around 400,000 years ago, traveling across an ancient land bridge from Asia, according to the Department of the Interior (DOI).

But even though bison and buffalo are similarly large, cattle-like animals, there are striking physical differences that distinguish them.

The American bison — which can weigh up to 2,000 lbs. (900 kilograms) — sports an unusually massive head and a considerable shoulder hump, both of which are covered with thick, woolly fur. The enormous, heavy muscles in the hump allow bison to use their heads as powerful snowplows in the winter, pushing aside masses of snow by swinging their heads from side to side, the NPS reported.

Bison's heads can also be used as battering rams, to drive off predators or to compete for females, according to the NPS.

By comparison, the buffalo of Africa and Asia have no hump whatsoever, and their skulls are smaller than those of bison. But while they may come up short on head size, both buffalo species more than make up for that in the breadth of their impressive horns.

Asian buffalo have large, crescent-shaped horns that curve upward and can span over 6 feet (2 meters) in length, according to the Encyclopedia of Life (EOL). Wild males can weigh over 2,600 lbs. (1,200 kg), though domesticated Asian buffalo, which are widespread across Asia, typically weigh about half as much as that — around 1,200 lbs. (550 kg), EOL explained.

African cape buffalo are native to the savannas and grasslands of southern, western, eastern and central Africa, and the animals usually congregate near water, according to the African Wildlife Foundation (AWF). Males are equipped with a head shield from which the horns sprout, sweeping downward before curling back up again, and can weigh as much as 1,500 lbs. (680 kg), the AWF reported.

Currently, about 10,000 wild bison still roam 12 states in North America, where the animals forage for an average of 9 to 12 hours each day for weeds, grasses and leafy plants, according to the DOI.

Originally published on Live Science.

Buffalo and bison are not the same animal. Typically, the big fluffy animals that people call buffalo are actually bison, while true buffalo look more like large bulls. The two are related though. Bison and buffalo are bovines (a subfamily of bovids), but bison are in a different genus from buffalo. Other relatives include antelopes, cattle, goats and sheep. 

There are two different species of bison: the American bison and the European bison. The American bison became the official national mammal of the United States when President Barack Obama signed the National Bison Legacy Act into law on May 9, 2016, according to the U.S. Department of the Interior. 

Size

The American bison is the largest mammal in North America. It grows to 7 to 11.5 feet (2.1 meters to 3.5) long from head to rump, and its tail adds an extra 20 to 23.5 inches. They weigh 930 to 2,200 lbs. (422 to 998 kilograms).

The European bison is the largest herbivore in Europe, according to Encyclopedia Britannica. It is around 9.5 feet (3 m) long. While it's around the same length as the American bison, it is typically heavier. It weighs a whopping 1,762 to 2,203 lbs. (800 to 1,000 kg).

Habitat

The American bison can be found in the United States, Canada and Mexico, mostly in conservation areas, preserves or farms. The European bison was once found throughout Europe. Now it is found in Poland, Belarus, Lithuania, Russia, Ukraine and Slovakia.

Habits 

Bison are social creatures and live in groups called herds. A herd usually contains females and their offspring. Males will either live near a herd of females or will belong to a herd that consists of other males. 

Bison are migratory animals. Herds migrate south in winter and move back north in the spring.

These large animals mate around August of every year. The males tend to fight and bellow for the choice females, but research shows that females may prefer the quieter males. "We were expecting to find that the bigger, stronger guys — the high-quality males — would have the loudest bellows, because they can handle the costs of it," said Megan Wyman, a graduate student in geography at University of California, Davis and the lead author of the study. "But instead, we found the opposite." 

Another surprising finding is that sometimes the males are more interested in other males. More than 55 percent of mounting tends to be young males with the same gender. [Related: Shh! Quiet Bison Get More Sex]

Diet

Buffalo are herbivores, which means they only eat vegetation. Typically, grass and herbs are on the menu, but they will also eat leaves and twigs. 

Offspring

Births usually occur between March and May. A female, called a cow, will give birth after a gestation period of nine months. Usually, she will give birth to only one young at a time, though twins have been recorded. 

A baby bison is called a calf. Calves are born big. American bison calves weigh a massive 30 to 70 lbs. (14 to 32 kg) at birth, according to the U.S. Department of Interior.

A calf is protected not only by its mother, but also by the whole herd. They are weaned at 7 to 13 months and typically become sexually mature at 2 to 3 years of age. Adult bison live around 14 to 24 years in the wild.

Classification/taxonomy 

Here is the classification of bison, according to the Integrated Taxonomic Information System (ITIS):

Kingdom: Animalia Subkingdom: Bilateria Infrakingdom: Deuterostomia Phylum: Chordata Subphylum: Vertebrata Infraphylum: Gnathostomata Superclass: Tetrapoda Class: Mammalia Subclass: Theria Infraclass: Eutheria Order: Artiodactyla Family: Bovidae Subfamily: Bovinae Genus: Bison Species: 

• Bison bison (American bison)
• Bison bonasus (European bison)

Conservation status

Millions of bison roamed North America in prehistoric times, according to the U.S. Department of the Interior. Many Native American tribes depended on the bison for food, clothing and shelter. But by the late 1800s, only a few hundred bison were left in the United States. As European settlers pushed west, they reduced the animal's habitat and hunted them to near extinction. 

Today, while not endangered, bison are not doing very well. The American bison is listed as near threatened by the International Union for Conservation of Nature (IUCN) Red List. This is due to the bison's dependence on conservation programs to survive. The American bison has only 19,000 total plains bison in 54 conservation herds and 11,000 total wood bison in 11 conservation herds, according to IUCN. There are 500,000 bison living on preserves and ranches, according to National Geographic.

The European bison is listed as vulnerable by the IUCN. The organization believes that there may be less than 1,000 mature European bison in existence.

Other facts

Both males and female bison have horns.

Bison are typically brown in color. Rarely, a white bison is born. These bison were worshiped by Native Americans. 

Bison are fast runners. They can run up to 40 mph (65 k/mh), according to Encyclopedia Britannica. 

When a bison's tail sticks straight up that means the animal is angry.

Additional resources

• Animal Diversity Web: European Bison
• Animal Diversity Web: American Bison
• U.S. Department of the Interior: Map of Bison in North America
• National Wildlife Federation: Bison

It's been around 11,000 years since giant ground sloths roamed North America, but evidence of one of them recently surfaced in Los Angeles, during excavation for a transit project managed by the LA County Metropolitan Transportation Authority.

Fossils from a giant sloth and a bison were unearthed on May 16 in a layer of sandy clay about 16 feet (5 meters) below Crenshaw Boulevard between 63rd Street and Hyde Park Boulevard, according to a post published online May 31 by The Source, a blog about the LA Metro.

The rocky fragments were identified on May 24 by Gary Takeuchi, collections manager at the La Brea Tar Pits and Museum, as pieces of leg bones — one belonging to a sloth and the other to a bison, LA Metro representatives said in a statement. [Image Gallery: 25 Amazing Ancient Beasts]

Fossils of other ancient massive beasts, which roamed North America during the last ice age, have unexpectedly appeared during other LA construction projects in recent years. In April, work on a subway line extension near the La Brea Tar Pits was temporarily halted while paleontologists recovered first a camel bone and then a bone from an elephant relative, a mammoth or mastodon. And in December 2016, workers discovered a skull and partial tusks, as well as a section of mammoth tusk, also close by the tar pits.

In fact, fossils such as these turn up more frequently in LA than you might think, Takeuchi told Live Science in an email.

"Fossils periodically are found during excavation due to construction in the LA area. These fossils would probably not have been found if it were not for this construction unearthing them," he said.

The fossil belonging to the bison is part of a front leg, while the sloth fossil is a femur-head fragment, The Source reported. In photos that show the new finds positioned next to complete bones from the same animals, the rough and fragmented fossils don't look like much. But the trained eye of a paleontologist can quickly puzzle out the animal — and body part — that they represent, Takeuchi explained.   

"The shape and size of the end of long bones can tell you what element in the body and what animal it belongs to," he said in an email. "You do not need the complete bone or animal for identification."

For now, the new finds will remain with experts at Paleo Solutions, a company that assists in the removal and preservation of paleontological and archaeological artifacts and objects that are found on construction sites. In time, the fossils will find a home with other ice age fossils, possibly at the Natural History Museum of Los Angeles County, The Source reported.

Original article on Live Science.

A herd of wild bison has been reintroduced to Banff National Park in Alberta, Canada, marking the first time that bison have roamed this part of Canada since they were hunted to near extinction in the 19th century.

Parks Canada — the Canadian government agency that manages national parks, conservation areas and historical sites — relocated the 16 bison, which primarily include pregnant females, to the remote Panther Valley in Banff National Park, the Calgary Herald reported. Initially, the bison will be in an enclosed pasture and monitored by Parks Canada officials, but by summer 2018, the herd will be free to roam across more than 460 square miles (1,200 square kilometers) in the Red Deer and Cascade river valleys, according to the Calgary Herald.

Banff National Park Superintendent Dave McDonough said the herd's release is part of a celebration of Canada’s 150th anniversary of Confederation, when the country was united into one dominion. [Photos: 9,000-Year-Old Bison Mummy Found in Siberia]

"It's a great event to have a keystone species return to one of our nation’s most iconic places," McDonough said when making the official announcement Monday (Feb. 6), according to news reports. "I'm proud to say that history has come full circle and wild bison are once again in Banff National Park."

Bison used to freely roam the land that is now Banff National Park, and their historic population in North America was about 30 million, the Calgary Herald reported. However, overhunting brought the large herd animals to the brink of extinction. To save the species, the Canadian government purchased one of the last surviving herds in the early 1900s, according to Parks Canada. For almost a century, this herd and its descendants were kept in a protected paddock at the base of Cascade Mountain in Alberta, before being released in 1997 to begin their reintroduction to the wild.

If the herd thrives, and a healthy wild population is established, the Banff plains buffalo population will be just one of four in North America that is roaming in the wild and interacting with its historical environment, said Karsten Heuer, bison project manager for Parks Canada.

"That will be a first in over 140 years in Banff National Park, and that's really why we're doing this, is to make them wild again," Heuer told the Calgary Herald. "They've been absent from this landscape for too long, and so I think today is the hooves-on-the-ground beginning of trying to bring that back."

Original article on Live Science.

Clever detective work involving research on both ancient DNA and cave paintings from the last ice age has revealed a previously unknown species of hybrid bison, according to a new study.

Researchers initially nicknamed the newfound bison the "Higgs Bison," because, just like the once-elusive subatomic particle known as the Higgs Boson, the bison's very existence had never been confirmed, and it took about 15 years to piece together data that proved its existence.

But now, thanks to ancient DNA from the creatures' bones, researchers know that the mysterious bison was a hybrid animal that originated more than 120,000 years ago, when the extinct aurochs (the ancestor of modern cattle) and the ice-age steppe bison got together, the researchers said. [See Photos of the Cave Art That Helped Experts Crack the Bison Mystery]

Usually, hybrid animals aren't too successful, mainly because the males tend to be sterile, said the study's senior researcher Alan Cooper, director of the Australian Centre for Ancient DNA at the University of Adelaide in Australia. But the newfound hybrid bison did quite well for itself and its descendants, the modern-day European bison (Bison bonasus), which is also known as a wisent. The European bison are still alive today, he said.

The Aurochs (Bos primigenius) and bison (Bison priscus) are "genetically quite different," Cooper told Live Science. "[But they] produced something that was successful enough to carve out a niche on the landscape and go on to become, ironically, the biggest species [of other large animals] to survive the extinction at the end of the ice age in Europe."

In addition, the discovery of the hybrid shows that the steppe bison, which was once thought to be the only bison in that region during the last ice age, likely competed with the hybrid species for tens of thousands of years, Cooper said.

Hybrid mystery

To solve the animal's mysterious genetic background, an international team of researchers examined the creature's remains — that is, its bones and teeth — which were unearthed from caves in Europe, the Ural mountains in Russia and the Caucasus mountains in Eurasia.

Then, the scientists studied ancient DNA from 64 different bison, including the creature's mitochondrial DNA (genetic material passed down through the mother's lineage) and nuclear DNA, or DNA passed down from both parents.

"We could see that the nuclear DNA was very obviously like the steppe bison," Cooper said. "The mitochondrial [was] telling us another [ancestor]: cattle."

The evidence suggested that the creature was a hybrid, likely started by a female Aurochs and a male steppe bison, he said. Moreover, the hybrid animal's nuclear DNA was about 90 percent steppe bison and 10 percent Aurochs, Cooper said.

"That ratio tells you that after the first hybridization event, there was back breeding with steppe bison for a little while, which is why the steppe bison DNA is higher," Cooper said. "That will often happen when you have a hybrid mammal, because the male [hybrid] offspring tend to be sterile." [Real or Fake? 8 Bizarre Hybrid Animals]

Cave paintings

However, the researchers have yet to find a hybrid skull, meaning they can't truly assess what it looked like and what it ate. One day, one of Cooper's colleagues suggested that he look at the ice-age cave art that covers the walls of caves throughout Europe.

That advice changed the trajectory of the entire project.

"We contacted some French scientists who work on the cave art and asked them, 'Have you ever noticed anything funny about the bison? Because we have [discovered] a second species," Cooper recalled. "They said, 'Ah, at last! Someone finally believes us. We've been telling our colleagues for years that there are two forms of bison in the cave,' which had been previously explained as artistic or cultural or stylistic differences."

One form depicted a bison with either long horns or large forequarters, much like the American bison, which is descended from the steppe bison. In contrast, the other form had shorter horns and small humps, much like the modern European bison, Cooper said.

In an unexpected turn, the dates of the drawings, some of them 18,000 years old, matched the ages of the radiocarbon-dated bison bones, the researchers added.

"The dated bones revealed that our new species and the steppe bison swapped dominance in Europe several times, in concert with major environmental changes caused by climate change," study lead author Julien Soubrier, a postdoctoral research associate in the genetics and evolution unit at the University of Adelaide, said in a statement.

In other words, ancient people drew the hybrid bison when it was thriving during colder, tundra-like periods without warm summers, and they drew the steppe bison when it thrived during different climates (which have yet to be determined), Cooper said.

The hybrid bison's descendant, the modern European bison, suddenly appears in the fossil record about 11,700 years ago, just after the steppe bison went extinct. In fact, the modern bison nearly went extinct during World War I, when just 12 individuals survived in the wild. Given that all of today's modern bison are descended from these 12 individuals, they look genetically different from the hybrid bison, even though they're likely the descendants of them, Cooper said.

The study was published online today (Oct. 18) in the journal Nature Communications.

Original article on Live Science.

DNA and drawings

Researchers have solved a puzzle about a mysterious bison in Europe by studying ancient DNA and cave paintings. They found that modern European bison appeared about 120,000 years ago, after the extinct steppe bison mated with the ancestors of modern cattle, making a hybrid animal. Moreover, cave paintings clearly show the difference between the hybrid animal and the steppe bison, showing that even ancient people noticed the difference between the two animals. [Read the Full Story About the Hybrid Bison]

DNA work

Researchers examine ancient DNA taken from the previously unknown hybrid species of bison.

Ancient DNA

Scientists extract ancient DNA from ground-up bison bones and teeth.

Bovid bones

Bones from the hybrid species of bison.

Cave paintings

Cave paintings from the Cave of Niaux in southwestern France. Some of the paintings the researchers examined were made 18,000 years ago, and depicted creatures with long horns and large forequarters that likely descended from the steppe bison. In contrast, more recent paintings from about 12,000 to 17,000 years ago show animals with shorter horns and smaller humps, much like the modern European bison.

European bison

The modern European bison (also called wisent or Bison bonasus) from the Białowieża Forest in Poland. [Read the Full Story About the Hybrid Bison]

Modern bison

Modern European bison have thick fur coats that help keep them warm during the winter. They also have short horns, much like the cave painting drawings of what is likely a hybrid creature.

Marsoulas artwork

A reproduction of the modern European bison in the Marsoulas Cave, located in Haute-Garonne, France. The original painting was created during the Magdalenian period, about 12,000 to 17,000 years ago.

Steppe bison drawing

A reproduction of a steppe bison (Bison priscus) cave painting that is made with charcoal. The painting was made during the Aurignacian period, about 28,000 to 40,000 years ago, in the Chauvet-Pont d’Arc cave in Ardèche, France.

Bison masterpiece

A drawing of a steppe bison (Bison priscus) that was made with black charcoal that dates from the Aurignacian period, located at the Chauvet-Pont d'Arc cave in Ardèche, France.

Charcoal painting

Another drawing of a steppe bison that ancient people made with charcoal from the Chauvet-Pont d'Arc Cave in France.

Short horns

A reproduction of what is likely a modern European bison dating to about 17,000 years ago from the Pergouset Cave in France. This modern bison is the descendant of the hybrid creature. [Read the Full Story About the Hybrid Bison]

What began as a well-intentioned but ill-informed act ended with the death of a young wild animal recently at Yellowstone National Park. And the incident carries a sobering lesson for people tempted to "help" wildlife that they believe to be in distress.

During the week of May 9, visitors to Yellowstone came across a solitary bison calf. Thinking it was abandoned, they took the animal into their vehicle and transported it to a park station. Later, the newborn calf was released back into the wild, and the National Park Service (NPS) issued the visitors a citation, according to a statement from the NPS released May 16.

But after the calf was released into the wild, it was repeatedly rejected by its herd and was endangering itself by approaching people and cars on the road, according to Charissa Reid, a public affairs specialist with Yellowstone National Park. Reid told Live Science that park rangers made numerous attempts to reunite the calf with a nearby herd but were unsuccessful, and eventually had no option but to euthanize the calf. [7 Iconic American Animals]

Reid said that the park visitors who transported the calf found it in the middle of the road in an area where cell phone reception was poor and they were unable to contact park officials. When their efforts to move the calf off the road were unsuccessful, they placed the calf in their car — an illegal act — and drove it to a ranger station. Reid told Live Science that in spite of rangers' repeated attempts to return the calf to a herd close by, the calf kept coming back to the road, creating a hazard for itself and for people.

"It seemed to be very imprinted on people rather than on bison," Reid said.

On social media, many people expressed concerns that euthanizing the calf seemed like a drastic action, and in a Facebook comment, a Yellowstone National Park representative responded to numerous questions about why the calf had to be killed.

The NPS is not equipped to care for a calf that can't forage on its own, and sending the calf outside the park would require months of quarantine to observe it for signs of brucellosis, a highly contagious bacterial infection that affects domestic animals and people, the rep said. However, "no approved quarantine facilities exist at this time," the Yellowstone representative added.

Park regulations dictate that visitors refrain from contact with all wild animals as a safety measure. In the case of young animals, human contact also can lead mother animals to reject their babies. But even when humans are not involved, bison mothers — especially young ones — will sometimes abandon their calves, which then typically succumb to predators or to starvation, the Yellowstone representative noted.

And the NPS does not intervene in those circumstances either.

"Our goal is to maintain the ecological processes of Yellowstone," the representative said. And though it might be difficult for park visitors to accept, naturally occurring animal deaths are one of those processes, the rep added.

The bison was officially designated as the United States' national mammal on May 9, joining the bald eagle as both a symbol of the country and a representative of significant conservation achievements. Bison were hunted to near extinction during the 19th century, and by 1902, only two dozen free-ranging bison remained in Yellowstone, according to the NPS. Regulations and preservation initiatives were introduced to help the species recover, and their populations have rebounded: As of July 2015, there were approximately 30,000 bison in public and private herds in the U.S., with 4,900 wild bison in Yellowstone.

These shaggy bovines are unquestionably charismatic, but when they're encountered in a national park, they are best appreciated from a distance — at least 25 yards (23 meters) away, according to NPS guidelines. And that's not just for their own well-being — approaching wild animals can have deadly consequences for people as well, the NPS warned.

The bison is North America's largest land mammal. Adult males stand 6 feet (2 m) tall and weigh up to 2,000 lbs. (907 kilograms), and females can weigh up to 1,000 lbs. (454 kg). For animals that are so heavy, they can run surprisingly fast — up to 30 mph (48 km/h).

In 2015, five Yellowstone park visitors were seriously injured after approaching bison from unsafe distances. Three of those visitors were taking photos, and two of them reported having their backs to the animals at the time, according to a Morbidity and Mortality Weekly Report released by the Centers for Disease Control and Prevention (CDC) on March 24.

In the NPS statement, officials called for park visitors to show respect for wildlife and park regulations, which were created to protect both animals and people. This is especially critical for visitors to remember when considering approaching wildlife that appears to need help, which could put them or the animal in jeopardy.

"The safety of these animals, as well as human safety, depends on everyone using good judgment," the NPS said.

Follow Mindy Weisberger on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on Live Science.

The bones of an ancient bison species that lived some 13,000 to 14,000 years ago have been discovered beneath the ground at Vero Beach, Florida, archaeologists announced.

The bones were unearthed at one of the oldest and most significant archaeological digs in North America, the Old Vero Man Site. That site was discovered in 1915 after construction in the area exposed human remains, artifacts, and flora and fauna dating from the late Pleistocene epoch (1.8 million to about 11,700 years ago). 

"About 100 years ago, the excavations at Vero … were the epicenter of the North American archaeological universe, because it was the very first site that was claimed with some support to demonstrate that humans and ice age animals were contemporaries on the North American landscape," James Adovasio, the principal investigator of the research, told Live Science.

An ancient mammal

The species Bison antiquus, also known as the "ancient bison," is a direct ancestor of the United States' new national mammal, the American bison. At 8 feet (2.4 meters) tall, 15 feet (4.6 m) long and nearly 3,500 lbs. (1,588 kilograms), the Bison antiquus was the most common large herbivore on the continent. For comparison, today's bison are smaller, at more than 6 feet tall and weighing about a ton (907 kg).

Lead archeologist Andrew Hemmings from from Florida Atlantic University's (FAU) Harbor Branch Oceanographic Institute said in a statement that this discovery is particularly exciting because of the human history of the area.

"We couldn't have asked for a better representative species from that era," Hemmings said. "We now know that people were here in Vero Beach at that time."

Bison found on land

Discovered only 10 feet (3 m) underground, the bones are the first of their kind to be uncovered on land, rather than underwater. Due to Florida's climate, bones will naturally disintegrate through the years as they're subjected to countless episodes of wetting and drying. [Photos: 9,000-Year-Old Bison Mummy Found in Siberia]

"This is the first time to our knowledge that the species has been recovered in a terrestrial excavation," Adovasio said.

Identified using an upper molar, the Bison antiquus bones will now undergo deeper examination and research at FAU's Ancient DNA Lab at Harbor Branch. 

The archaeologists also uncovered bone slivers that could have come from large ancient mammals like mammoths, mastodons, sloths or bison. Other discoveries at the Old Vero Man Site include the bones of smaller mammals, the head of a fly and pieces of charcoal — a sign of humans in the area.

"What is unique about Vero now is what it's promising to tell us about the nature of the lifestyles, if you will, of the first Floridians," Adovasio said. "I think Vero just adds a piece of the mosaic that we're trying to put together to understand what the first colonists of the New World had to face and what their responses to those environments might have been."

Follow Kacey Deamer @KaceyDeamer. Follow Live Science @livescience, on Facebook & Google+. Original article on Live Science.

Yellowstone National Park has seen a rise in people getting injured by bison lately, and attempts to take selfies may be to blame for at least some of these injuries, according to a new report.

In the summer of 2015, five people were injured by bison in Yellowstone. That's more than the number of bison-related injuries seen annually in 2010 through 2014, when there were one or two injuries per year, according to the report from researchers at the Centers for Disease Control and Prevention.

Four of the people injured in 2015 were visitors to the park, and one was an employee. In three of the cases, people were injured when a bison tossed them into the air, and in the other two cases, a bison injured the individual with its horns. None of the injured died, although four needed to be hospitalized for their injuries, the report said.

All of the injuries occurred when people got too close to the bison. The iconic animals roam freely throughout the park, but they can be dangerous, and park rules prohibit visitors from coming within 75 feet of bison. Most of the people injured in 2015 were within 3 to 6 feet of the bison just before they got hurt, the report said.

Three people in the report were injured while taking photos. Two of these reported turning their backs toward the animal to snap their photos, and one admitted outright to trying to take a selfie, the report said. [Top 10 Most Visited National Parks]

The report noted that from 1980 to 1999, about 30 percent of bison-related injuries involved photography, and most of the people injured during that period were standing more than 10 feet from an animal.

But with today's smartphones, more people are taking photos and selfies, and because the devices don't zoom in very well, people may need to get closer than they did before. "The popularity of smartphone photography with its limited zoom capacity and social media sharing of selfies might explain why visitors disregard park regulations and approach wildlife more closely than when traditional camera technology was used," the report said.

Male bison can weigh up to 2,000 pounds, and females can weigh up to 1,000 pounds. Yet the animals are agile for their size, and can run up to 30 miles per hour. There were nearly 5,000 bison in Yellowstone in 2015, according to the National Park Service.

Educating visitors about the need to maintain a proper distance between themselves and wildlife is critical, the report said. "Injury prevention campaigns that identify and target the underlying motivations of visitors to not comply with viewing distances might prevent future injuries," the researchers, led by CDC epidemiologist Dr. Cara Cherry, wrote in their report.

Selfies have been blamed for deaths and injuries before. Last year, officials in Russia launched a campaign warning of the dangers of selfies after a number of selfie-related injuries and deaths occurred in the country, including one teenager who died while trying to take a selfie on a railway bridge.

The new report was published yesterday (March 24) in the CDC's Morbidity and Mortality Weekly Report.

Follow Rachael Rettner @RachaelRettner. Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.

This story was updated at 11 a.m. ET on Nov. 7.

Hidden away under frozen ground for nearly 10,000 years, an extremely well-preserved bison mummy is finally ready to give up its secrets.

In 2011, members of the Yukagir tribe in northern Siberia discovered the remains of a steppe bison (Bison priscus), an extinct ancestor of the modern bisonthat still roam the plains of North America and northern Europe. The almost perfectly preserved bison was transported to the Yakutian Academy of Sciences in Siberia, where researchers made plans to perform a necropsy, an autopsy performed on animals.

While other steppe bison mummies have been discovered over the years, none have been as well-preserved as the so-called Yukagir bison mummy, which was found with its internal organs almost completely intact, according to Olga Potapova, the collections curator and manager at the Mammoth Site of Hot Springs in South Dakota, who helped study the ancient mammal. [Photos: 9,000-Year-Old Bison Mummy Frozen in Time]

"Normally, what you find with the mummiesof megafauna in North America or Siberia is partial carcasses. They're partly eaten or destroyed because they're lying in the permafrost for tens of thousands of years," Potapova told Live Science. "But the mummy was preserved so well that it [earned] a record for the level of its preservation."

The researchers think the Yukagir bison died young, at about 4 years old, Potapova said. The lack of fat around the bison's abdomen suggests the animal died of starvation.

But other than that missing layer of fat, the bison was very well-preserved, with its heart, blood vessels and digestive systemfound relatively in tact, though some of the organs had shrunk significantly, the researchers said. The specimen was so well-preserved that researchers were able to obtain tissue samples from each organ, Potapova said.

The bison mummy's brain was also very well-preserved, according to Albert Protopopov, chief of the mammoth fauna research department at the YakutianAcademy of Sciences. And this is the first time that a steppe bison's brain tissue has been found intact, Protopopov told Live Science via Potapova, who translated his statements.

The bison's brain was removed from the animal's skull for further study, and the preliminary histology — or study of the brain tissue— is still underway, Protopopov added.

In addition to removing the bison's brain, the researchers also took out the rest of its internal organs, to study the tissues. The goal of the research is to collect data about this ancient bison that can then be used to compare it to modern bison species, said Natalia Serduk, a senior researcher at the Russian Academy of Sciences in Moscow, who is also involved in the study.

To confirm that this frozen mammal really was a steppe bison, the researchers used mitochondrial DNA found within the animal's tissues to perform a species identification test. They used carbon dating to determine how long ago the animal lived, Serduk told Live Science via Potapova, who translated her statements.

"Anatomy, physiology, genetics — these give us very good information to construct the bison's habitat, behavior and style of life. If we get all this information, we'll be able to pin down the real reasons for the extinction of the species," Potapova said.

The findings were presented at the annual meeting of the Society of Vertebrate Paleontology in Berlin and will be published in the Journal of Vertebrate Paleontology.

Editor's Note: This story was updated to correct a statement on how mitochondrial DNA from the mummy was used by the researchers.

Follow Elizabeth Palermo @techEpalermo. Follow Live Science @livescience, Facebook & Google+. Original article on Live Science .

Leroy Little Bear is Professor Emeritus at the University of Lethbridge and Tribal Elder for the Blood Tribe; Ervin Carlson is the Blackfeet Nation Bison Program manager and President of the Intertribal Buffalo Council (ITBC); Angela Grier is a Piikani Tribal Council member; Tommy Christian of the Fort Peck Tribal Council; and Chief Earl Old Person of the Blackfeet Nation is advisor for the National Mammal Campaign and a Tribal Council member. The authors contributed this article to Live Science's Expert Voices: Op-Ed & Insights.

For tens of thousands of years, buffalo fundamentally shaped Native American cultures and engineered the ecology of prairie ecosystems. Immense herds grazed and enriched the grasslands and mountain foothills across North America. Acting as a natural bio-engineer in prairie landscapes, they shaped plant communities, transported and recycled nutrients, created habitat variability that benefited grassland birds, insects and small mammals, and provided abundant food resources for grizzly bears, wolves and humans. 

More than any other species, the buffalo — American bison , or iiniiwa in Blackfoot — linked native people to the land, provided food and shelter, and became a central figure in our ancient cultures. Following the great slaughter of the 19th century, the buffalo has been missing from most of these lands and our cultures. There is growing recognition that the absence of buffalo has led to deterioration of the ecological integrity of grasslands, diminished the health of our people, and led to an incalculable cultural loss. 

This is why on Sept. 23, we hosted a tribal treaty convention in our Blackfeet Territory to commit the northern tribes and First Nations along the Medicine Line (the international boundary with Canada) to promote the conservation of prairies and the repatriation of American bison. 

To achieve our vision, the treaty calls for engagement with researchers and partners in federal, state and provincial governments; farmers and ranchers; conservation groups; and Native American youth. The "Buffalo Treaty" represents an important step by native people to practice conservation while preserving our cultures . We propose that this historic buffalo treaty will be but a first step, begun by native people, to create a national agenda to bring buffalo home and enable an important healing for the egregious treatment buffalo received at the turn of the 19th century. 

Collapse of the Great Plains

With the arrival and expansion of European Americans across North America, the northern Great Plains region has undergone more than a century of fragmentation, which has disrupted important ecosystem functions of native grasslands and relegated wildlife to small parcels of protected lands. This fragmentation has had its greatest impact on highly migratory species like buffalo that require large, intact landscapes. 

Once numbering in the tens of millions, buffalo came to the very brink of extinction due to unsustainable harvest and habitat destruction during the late 1800s. In what was the first wildlife restoration effort in the world, buffalo were saved through the persistent efforts of early conservation champions like Theodore Roosevelt, William Hornaday, Ernest Thompson Seton and others who invented a new conservation model for the world. Although these champions did preserve buffalo through their monumental efforts, it was primarily on small fenced landscapes. Ecological restoration will require extensive, native prairies that can support free-roaming buffalo that can fulfill their natural ecological role — therefore, preserving the prairies is critical to any option for restoring and recovering American buffalo.  [A Great American Conservationist: Remembering Teddy Roosevelt ]

Disappearance of wild buffalo in the Great Plains has led to cultural disruption among native people who associate the loss with a national movement to subjugate them. Our people still maintain a deep relationship to the land and wildlife, but unfortunately are no longer able to fully express that relationship because of the absence of buffalo. That loss has diminished the rich, deep relationship that existed before the extermination of these animals. 

Restoring some aspects of the physical, spiritual and cultural relationship with buffalo could inspire a new future for the prairie grasslands and its people. Developing a modern, culturally relevant vision for the conservation of iiniiwa could lead to unique opportunities to restore ecological, spiritual and cultural integrity to prairie ecosystems managed by native peoples.

Tribes and First Nations in Canada and the United States own and manage a vast amount of intact prairie habitat across the Great Plains and mountain foothills of the western United States. These intact grasslands provide suitable habitat for American buffalo if they remain intact, unfragmented and in their natural state. Native peoples of the northern Great Plains are culturally disposed to protecting their homelands, connecting with free-roaming buffalo, and have expressed considerable interest in their repatriation to native landscapes. Individually, each tribe may have limited resources and influence to achieve this grand vision of buffalo restoration.  

However, our combined voice and expressed political unity will help us achieve broader support for ecological restoration and the enrichment of tribal cultures. In addition, as individual tribal buffalo programs emerge it can inspire a national agenda to attempt what once seemed unlikely for an oppressed people.  

We call on the public, federal and state natural resource agencies, and the conservation community to support our intentions and help return iiniiwa to its rightful place in prairie ecosystems and native cultures.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook, Twitter and Google+. 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.

Buffalo are large members of the Bovidae family. There are two types of buffalo: the African or Cape buffalo and the Asian water buffalo. They are dark gray or black animals that look a lot like bulls.

Buffalo are often confused with bison. Early American settlers called bison "buffalo" because the animals are similar in appearance. However, while bison are also bovines (a subfamily of bovids), they are in a different genus from true buffalo. Other bovines include domestic cattle, oxen, yaks, four-horned antelopes, bongos and kudus, according to the Integrated Taxonomic Information System (ITIS).

Size

The water buffalo is the largest bovine. It is 8 to 9 feet (2.4 to 2.7 meters) from head to rump with its tail adding an extra 2 to 3.3 feet (60 to 100 centimeters). They weigh a massive 1,500 to 2,650 lbs. (700 to 1,200 kilograms). The African buffalo is smaller, but they are still quite impressive in size. They are 4.26 to 4.92 feet long (130 to 150 cm) from head to hoof and weigh 935 to 1,910 lbs. (425 to 870 kg). 

Habitat

Water buffalo live in the tropical and subtropical forests of Asia. They are aptly named, for they spend most of their time in water. Their hooves are extra wide and prevent them from sinking into mud at the bottom of ponds, swamps and rivers.

The African buffalo is never far from water. They can live in grasslands, savannas, swamps, lowland floodplains, mixed forest and glades, but they never roam farther than 12 miles (20 kilometers) from a body of water, according to the Encyclopedia Britannica. Instead of spending their days taking a swim, though, they lie under trees to keep cool while they nap. At night, they like to graze in the cool air.

Habits 

Buffalo are social animals and live in groups called herds. Water buffalo herds are segregated by gender. Young males stay with the maternal herd for about three years, and then they join a male herd. Maternal herds have up to 30 females and their offspring. Male herds have up to 10 members. African buffalo herds are mostly of mixed gender. They do have a few all-male herds, but these usually consist of old males. An African herd often has more than 1,000 members. 

Diet

Buffalo are herbivores, and so eat only vegetation. Their favorite foods are grass and herbs, but water buffalo will also eat aquatic plants. Both African and Asian buffalo will eat shrubs and trees when they can't find grass or herbs to eat.

Offspring

Buffalo, like most mammals, bear live young, which are called calves. Usually, they have one calf at a time, and the female will carry the calf for a gestation period of 9 to 11 months before giving birth. Once the calf is born, a water buffalo will stay with its mother for around three years. Then, male calves will be moved to the all-male herd, while the female calves stay with the female herd. Females become pregnant every other year.

Water buffalo tend to live around 25 years, according to the University of Michigan, while African buffalo live around 26 years.

Classification/taxonomy 

The taxonomy of buffalo, according to ITIS, is:

• Kingdom: Animalia 
• Phylum: Chordata
• Class: Mammalia 
• Order: Artiodactyla 
• Family: Bovidae 
• Subfamily: Bovinae 
• Genera and species: Syncerus caffer (African buffalo) and Bubalus bubalis (water buffalo)

Conservation status

Water buffalo were domesticated more than 5,000 years ago. Humans use the meat, milk, horns and leather. Buffalo are also used for transportation and to pull plows. Wild water buffalo are endangered, according to the International Union for Conservation of Nature. They have a population of less than 4,000, though it is uncertain what the exact numbers are. 

The African buffalo is not endangered and has a population of 900,000, according to the African Wildlife Foundation. 

Other facts

Male water buffalo have horns that curve backward. These horns can grow to 5 feet (1.5 meters) long. Females also have horns, but they are much smaller.

African buffalo have a democracy. When they are ready to travel, they will stand and turn in the direction they want to go. The majority of "votes" wins and the head female will lead the herd in the winning direction.

African buffalo are very aggressive and have a tendency to attack humans. They are very protective of each other and take care of sick and old members of the herd, shielding them from predators. 

Other resources

• National Geographic: Water Buffalo
• Encyclopedia Britannica: Water Buffalo
• University of Michigan Museum of Zoology: Water Buffalo
• BBC Nature: African Buffalos

Bison went extinct in Europe nearly 100 years ago, but conservationists are taking small steps to bring the animals back into the wild.

Seven female bison raised in captivity in the British Isles will be reintroduced to a forest in Romania, officials with the Royal Zoological Society of Scotland (RZSS) announced.

The creatures arrived at Vanatori Neamt Nature Park, Romania, on April 25. They will spend the next several weeks in a large enclosure to get used to their new home before being released.

One of the bison, a female named Glen Rosa born in July 2012, was raised at Scotland's Highland Wildlife Park, which is operated by the RZSS. [Photos: The World's Biggest Beasts]

"Glen Rosa and the other bison will join an already established herd in Vanatori Neamt Nature Park, Romania, to help augment both numbers and genetic diversity within the group," Douglas Richardson, head of living collections for Highland Wildlife Park, said in a statement. "This is an excellent example of how zoos within the European Zoo Association's coordinated breeding programs are helping save species from extinction."

European bison (Bison bonasus) are the largest herbivores in Europe. The animals went extinct in the wild in 1927, but small populations were maintained in zoos. The first captive-bred bison was released into its natural habitat in 1952. Because of continued conservation and reintroduction efforts, the total wild population reached over 3,000 by 2012. The species is considered "vulnerable" by the International Union for Conservation of Nature (IUCN).

Bison had a similar trajectory in the United States. Tens of millions of the animals once roamed the Great Plains, but by the early 1900s, their numbers had dwindled to fewer than 1,100 individuals, largely due to overhunting and habitat loss. Thanks to early conservation efforts, bison made a comeback. Today, there are estimated to be hundreds of thousands of the animals across the nation.

Follow Megan Gannon on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on Live Science.

North America's largest land animal will roam the Alaskan wilderness once again if a plan unveiled last week is approved.  

Wood bison, a subspecies of the more familiar plains bison, once lived throughout Alaska and much of western Canada but haven't been seen in the state's wilderness for more than a century due to hunting and other factors. That may be about to change: The U.S. Fish and Wildlife Service announced a plan Jan. 17 to reintroduce the beasts, according to the Alaska Dispatch, a news website.

Several groups have been trying to reintroduce wood bison for more than a decade. Some Alaskans have rejected the idea of introducing an animal listed under the Endangered Species Act for fear that this might interfere with gas and oil development, the Dispatch reported. (Habitats of endangered animals often cannot be used for certain commercial activities.)

Under the new plan, the Alaskan bison would be designated as a "nonessential experimental population" that isn't necessary to the survival of the species, which has rebounded enough in Canada to be considered threatened, as opposed to endangered as was the case previously.

If their population reaches a certain size, the animals would also be fair game for hunters, according to the plan. Alaska natives would get the first crack at them, but the Fish and Wildlife Service said that the plan is to eventually open the herd to the public, given certain constraints.

A public comment period on the plan has begun and ends in two months. Assuming that the plan goes through, which depends upon input from the public and wildlife experts, reintroduction could begin by next spring, Reuters reports.   

A total of 132 animals already live in captivity at the Alaska Wildlife Conservation Center in Portage. Under the plan, they would be reintroduced to a grassland area near the lower Innoko and Yukon rivers, according to the Dispatch.

Wood bison are larger than their plains cousins, with adult bulls weighing up to 2,000 pounds (900 kilograms) or more, according to a statement from the U.S. Fish and Wildlife Service. In the early 1800s, there were as many as 168,000 throughout Canada and Alaska. Now there are 10,000 free-ranging wood bison in Canada, including about 4,500 in seven free-ranging, disease-free herds, the agency noted.

"Establishing wild populations of this magnificent animal in Alaska would be a significant step toward its eventual recovery and delisting" from the Endangered Species List, said regional director Geoffrey Haskett in the release. 

Wood bison have already been introduced to Russia, where scientists are trying to establish breeding populations of the animals, according to the Edmonton Journal. Wood bison are the closest living relatives to the steppe bison, which went extinct about 5,000 years ago.

Reach Douglas Main at dmain@techmedianetwork.com. Follow him on Twitter @Douglas_Main. Follow OurAmazingPlanet on Twitter @OAPlanet. We're also on Facebook and Google+.

A new bison calf born this summer at the Bronx zoo is a hopeful sign for the iconic American species, which was almost hunted to extinction, but is now making a resurgence.

Very few herds of purebred bison remain in North America. Two of these herds live in Wyoming's Yellowstone National Park, but breeding them outside the park has proven difficult, until now.

On June 20 a healthy male purebred bison calf was born after its embryo was transferred from a purebred Yellowstone bison to a commercial bison at the Bronx Zoo in New York.

The transfer was carried out by researchers at Colorado State University, led by reproductive physiologist Jennifer Barfield. [Ten Species Success Stories]

"The Bronx Zoo has been working for years to secure pure bison to establish a breeding herd that could supply animals for restoration programs," Pat Thomas, vice president of the Wildlife Conservation Society and Bronx Zoo general curator and associate director, said in a statement. "Dr. Barfield and her team have provided an innovative way to rescue these valuable genes and allow us to create this important herd."

Breeding Yellowstone bison outside of the park has been difficult, because the animals there are exposed to diseases such as brucellosis, which reduces female fertility and milk production and can cause miscarriage. For that reason, the Yellowstone bison have been quarantined there and restricted from spreading to other areas.

To get around the threat of disease, the scientists extracted an embryo from a Yellowstone bison that had been exposed to disease, then washed the embryo to cleanse it of sickness, and implanted it in the uterus of a disease-free female bison.

"In Yellowstone, the bison do not have trouble reproducing," Barfield said. "It's the process of removing animals that have been exposed to disease from the park so that their valuable genetics can be incorporated into other herds or used to create new herds that is the problem."

American bison once roamed the grasslands of North America in huge herds, but their numbers were devastated in the 19th century, when they were hunted for their hides. Bison skins were prized for use as clothing, rugs, and in factory machine belts.

This slaughter was encouraged by the U.S. government, which advocated bison hunting to free up grazing land for commercial cattle, and to thwart Plains Native Americans, who relied on the mammals for survival.

A population that started around 30 million was reduced to a few hundred by the mid-1880s.

In 1905, when the utter extinction of bison seemed imminent, Theodore Roosevelt and conservationist William Hornaday formed the American Bison Society to fight for the survival of the species. Since then, bison conservation efforts have helped the bison population recover, though not nearly to its former glory.

Follow Clara Moskowitz on Twitter @ClaraMoskowitz or LiveScience @livescience. We're also on Facebook & Google+.

The central portion of the United States was once called a sea of grass. Bison were the whales of those seas until being nearly hunted to extinction. The sea of grass was then given over to waves of grain, cattle ranchers and thousands of miles of barbed wire fence.

The American Prairie Reserve organization is trying to buy back the sea of grass, one ranch at a time. They hope to eventually piece together a three million acre preserve that will rival Africa's Serengeti and resemble the landscape Lewis and Clark traveled through more than two centuries ago. The land will remain open for the public to explore and enjoy, according to the organization's website.

The 150,000-acre South Ranch in Montana was founded by two bison-hunting Civil War veterans after the bison had been wiped out. Now, it is the cattle ranch that has been wiped out to make room for the bison. The ranch's owners recently sold the land to the American Prairie Reserve, reported the AP.

ANALYSIS: Buffalo Could Become National Mammal

Buying land for a preserve isn't a new idea. The aristocracy of the world maintained game preserves in ancient times. Unlike those ancient hunting preserves, the goal of the American Prairie Reserve is not to provide meat and sport for the wealthy, but to restore one of the most endangered ecosystems in America.

The purchase of the prairie did have some help from the modern-day version of aristocracy. Candy bar billionaires, John and Adrienne Mars, donated $5 million to American Prairie Reserve.

Not everyone is happy with the bison-benefiting business transaction.

"They keep saying they're saving it. But it already looks beautiful. They're not saving anything," rancher Vicki Olson told the AP.

Olson is in no danger of losing the ranchland views she finds beautiful. The vast majority of the former prairie remains beneath the cattles' hooves and is bound with barbed wire. Although hundred of bison now roam 14,000 acres of the American Prairie Reserve's lands, they are kept from straying by an electric fence.

ANALYSIS: Will Bison Roam Europe's Mountains?

Prairie dogs and the endangered black-footed ferrets that feed on them are also finding a home where the buffalo roam and the pronghorn antelope play on American Prairie Reserve land. Foxes and cougars are also found on the restored prairie.

This story was provided by Discovery News.

American Icons

American flags will be flying high on the Fourth of July, and Uncle Sam look-alikes will be out at the fireworks displays. But these symbols aren't the only American icons, which can be found aplenty in the amazing animal species found from sea to shining sea.

From the official symbols, such as the bald eagle, to the animals that conjure a specific piece of Americana, like the grizzly bear, the following animals are true American icons.

Bald Eagle

The quintessential American animal icon. These majestic creatures have a wingspan of about 7 feet (2 meters) and can fly between 75 to 99 mph (121 to 159 kph) in a hunting dive.

Bald eagles are unique to North America and live in coastal and lake areas from Baja California and Florida north to Newfoundland and Alaska.

Bald eagles became endangered due to the combined pressures of habitat destruction, hunting and the use of the poison DDT (used to dust crops), which caused eagle shells to thin and often break before hatching. The ban of DDT and other conservation measures have brought the species back from the brink; the bald eagle was removed from the Endangered Species List in 2007.

The bald eagle became a national emblem in 1785, after a drawing of the eagle was presented to the newly-formed Congress, according the U.S. National Archives. The pick wasn't universally popular though, as Benjamin Franklin preferred another bird. More on that in a bit.

Bison

The bison, informally called a buffalo, is North America's largest land mammal, with adult males typically weighing up to 2,200 pounds (1,000 kilograms). Some 30 million to 60 million of the animals once roamed the Great Plains.

But by the early 1900s, after decades of hunting, bison numbered less than 1,100. In 1905 President Theodore Roosevelt and a diverse group of other Americans established the American Bison Society to save the animal from extinction.

Bison have long been a symbol of the American West, and are a key species in the grassland ecosystem. They are also an important cultural symbol to many Native American groups.

The Wildlife Conservation Society and other groups recently launched a campaign to make the bison the United States' national mammal.

Mountain lion (cougar)

This creature goes by a multitude of names: mountain lion, cougar, catamount, and puma are just a few.

The species was once one of the most widely distributed in the Western Hemisphere, but only western cougars survive in significant numbers, with eastern cougars presumed extinct though still protected by the Endangered Species Act.

Early American settlers thought the mountain lion was a threat to themselves and their livestock and so hunted and trapped them until the cougar was largely wiped out from the region. Recent evidence, such as tracks and camera trap photos, has suggested that the cougar could be re-establishing itself in parts of its former territory in the Midwest.

Prairie dog

Black-tailed prairie dogs (Cynomys ludovicianus) are found only in the grassland prairie of North America, and their little heads popping up from the ground are an indelible image.

An estimated 24 million black-tailed prairie dogs are found across 2.4 million acres of prairie and their historic range includes 11 U.S. states.

The prairie dogs live in underground burrows, and the species emits a wide range of noises to communicate. They are a very social and territorial animal.

The underground tunnels that the prairie dogs dig help aerate the deep roots of the prairie grasses and allow rain water to reach several feet below the surface, making them a key part of the ecosystem.

Wild turkey

If Ben Franklin had had his way, the turkey would have been the national emblem of the United States over the bald eagle. As it is, the turkey gets the "honor" of being the dish of the national holiday, Thanksgiving.

Adult male turkeys, called toms, like to impress the females, called hens, with their tail feather displays. And it may come as a surprise that turkeys can fly, though not fast or high.

Early Americans significantly impacted turkey numbers through hunting, with only about 30,000 wild birds in existence in the 1930s. Conservation efforts have brought those numbers up to about 7 million today. Their range covers the bulk of the eastern half of the United States and parts of the West, extending down into parts of Mexico.

Wild turkeys are usually found in wooded areas and they roost at night in the low branches of trees.

Grizzly bear

Grizzlies are an iconic animal of the western United States. When Lewis and Clark made their great expedition of the West in the early 1800s, there were an estimated 50,000 grizzly bears between the Pacific Ocean and the Great Plains, according to the U.S. Fish & Wildlife Service. But as pioneers moved in, the grizzlies were hunted and their habitat disappeared with the emergence of towns and cities.

Today, grizzly bears thrive in only a few small pockets of habitat, such as in the Yellowstone area, in the lower 48 with an estimated 1,200 to 1,400 wild grizzlies. The species was listed as threatened in the lower 48 states under the Endangered Species Act in 1975.

Grizzly bears, also called brown bears, derive their named from their frosted, or grizzled, coats. They stand about 5 feet (1.5 meters) tall when on all fours and males can weigh up to 1,000 pounds (450 kilograms). They hibernate in the winter in dens and spend a third to a half of their life sleeping like this.

American alligator

he American alligator is one of only two true species of alligator (the other being the Chinese alligator), and an iconic sight in the swamps of the Southeast and Gulf Coast.

American alligators were once on the brink of extinction, but listing as an endangered species in 1987 has allowed them to recover.

Alligators are often seen submerged in the water, with their nostrils poking out. Their nostrils face upward so that they can breathe in this position.

Male American alligators average about 11 feet (3.5 meters) in length, but can grow up to a whopping 20 feet (6 m) long.

The bald eagle is well-known as an American symbol ? it has been the national bird since independence ? but now conservationists and other groups want to give the United States a national mammal, too: the bison.

"The bison is quintessentially American," said John Calvelli, executive vice president of public affairs for the Wildlife Conservation Society, one of the groups supporting the nomination. "What better way to celebrate the bison's remarkable history in U.S. culture than to make it the national mammal?"

The WCS, Intertribal Buffalo Council and National Bison Association recently launched a campaign to make the American bison the country's official mammal, and Sens. Michael Enzi, R-Wyo., and Tim Johnson, D-S.D.,  have introduced the National Bison Legacy Act at the request of a coalition of bison producers, tribal representatives and conservationists who would celebrate the first Thursday of each November as National Bison Day.

The coalition's campaign asks the public to "vote for bison" and highlights the many ways bison have shaped America's history, economy, culture and landscape. The public will have the opportunity to follow the national campaign and get involved in the legislative process by visiting www.votebison.org.

The bison, informally called a buffalo, is North America's largest land mammal, with adult males typically weighing up to 2,200 pounds (1,000 kilograms). Some 30 million to 60 million of the animals once roamed the Great Plains. But by the early 1900s, after decades of hunting, bison numbered less than 1,100.

In 1905 President Theodore Roosevelt, William Hornaday of WCS (then the New York Zoological Society) and others convened a group of diverse stakeholders at the Bronx Zoo in New York City and formed the American Bison Society. The society developed a new conservation ethic and helped save bison from extinction. Two years later, the society sent 15 Bronx–born bison to the first big-game refuge in the United States: the Wichita Reserve Bison Refuge.

Today bison number in the hundreds of thousands in the United States and are found in state and national parks, wildlife refuges and on tribal and private lands.

A coalition of conservationists, bison ranchers and Native American groups have nominated the American bison to be the US national mammal. What do you think it should be?

The National Bison Legacy Act declares that bison are integrally linked to Native American culture, are a keystone species that benefit grassland ecosystems, hold significant value for private producers and rural communities, and are a symbol of the American West.

"Recent discoveries by western scientists, combined with ancient traditional knowledge, have described many important relationships that large herds of bison maintained with other animals such as birds, amphibians and prairie dogs in a complete prairie system," WCS senior conservationist Keith Aune said in a statement. "Bison were a force of nature and served a key role in maintaining an entire ecosystem while providing important ecological services to mankind."

Follow OurAmazingPlanet for the latest in Earth science and exploration news on Twitter @OAPlanet and on Facebook.

The bleached animal skull, that icon of the Old West, could be a key to understanding how animal populations change. A new study suggests that bones of animals that died in recent decades match actual populations stretching back as much as a century.

Surveying these bones could be more useful than counting live animals when it comes to reconstructing old ecosystems, researchers reported March 28 in the open-access journal PLoS ONE.

"The skeletons of long-dead animals lying on landscapes provide critical insights into our understanding of ecosystem history," biologist Joshua Miller of Wright State University in Ohio said in a statement released by the National Science Foundation, which funded the research.

Researchers are accustomed to looking to the fossil record to reconstruct times gone by. Similarly, newer, unfossilized bones could give a glimpse into more recent history — as long as you are sure that the bones are a faithful record of the animals that died in an area, Miller wrote in PLoS ONE. [Read: Yellowstone Wolves Reintroduce 'Ecology of Fear']

Some bones might be preserved more readily than others, or they might not be preserved well enough for accurate age estimates.

Yellowstone was an ideal place to test the idea, Miller wrote, because wildlife surveys there have been very thorough. Over three years, he and his colleagues combed through the park, which predominantly lies in northwest Wyoming, counting bones and body remnants of large grazing animals, including bison, elk and moose. They surveyed along 40 narrow strips of grassland, forest, marsh and river and lakefront land, each 1 kilometer long and 30 to 100 meters wide (0.6 miles by 98 to 328 feet). They then compared their counts with recent aerial counts of Yellowstone's wildlife and with historical surveys.

Miller found that the counts didn't quite match up with modern numbers. But when he used weathering and radiocarbon dating to estimate a time of death for the animals found, the numbers matched perfectly with historical data.

"Elk, for example, were much more abundant in the 1990s than they are today," Miller said. "The bones of Yellowstone feature far more elk than one would predict based on the current Yellowstone community."

Horses were prevalent in the park in the late 1880s and early 1900s, before cars replaced them as transportation; weathered horse bones are still found in the park. By contrast, mountain goats showed up in the park in only the last 20 years; their skeletal record is almost invisible because relatively few have died so far. 

Yellowstone has been a well-studied area, Miller said, so the bone surveys didn't provide much new information about its history. The next goal, he said, is to take the technique elsewhere.

"Now we can go the next step and use bone accumulations in regions we have only recently begun studying to obtain critical historical data, and establish how ecosystems have changed over the last decades, century or even longer," Miller said.

You can follow LiveScience senior writer Stephanie Pappas on Twitter @sipappas.

Just because bison are big hasn't saved them from getting pushed around — the iconic American animal's dramatic scrape with extinction is a familiar tale of the American West and its settlement. Today, most of the herd is penned in, but a group of supporters are aiming to revive the wild population.

In the 17th century, the bison was the most abundant large mammal in North America. Estimates of their former populations on the Great Plains range from 30 million to 60 million individuals. People once told of herds so large it took days for them to pass by. Yet by the early 20th century, after years of indiscriminate slaughter for their valuable hides and bones, only about 1,000 bison existed on Earth.

"And fewer than 200 of those were in the wild," said Kent Redford, director of the Wildlife Conservation Society Institute and a leader at the American Bison Society (ABS).

Thanks to action by a few private individuals and some government protection, the few animals that survived have given rise to the 400,000 or 500,000 bison alive today. [Related: Ten Species Success Stories.]

However, despite their starring role in what Redford calls "one of the most successful conservation stories in this country," Redford says the massive beasts still need a champion.

This week, dozens of such bison champions can be found at a nondescript Marriott hotel in Tulsa, Okla. There, amid a sprawl of parking lots and mid-rise office buildings, where the only thing that calls to mind the majesty of nature is the names of the conference rooms (Silver Oak, Sequoia), the ABS will attempt to help determine the fate of wild bison.

The organization is holding its third meeting since Redford, at the behest of the Wildlife Conservation Society, revived the ABS in 2005, a century after the group was founded by Teddy Roosevelt and William Hornaday at the Bronx Zoo in New York City.

Private vs. public

Up to 95 percent of bison alive today are in private hands being raised for meat, Redford said, and members of the ABS would like to see those percentages shift.

"We're not against commercial production of bison, but we created a community that is interested in re-establishing bison as ecological actors on the stage of North American grasslands," Redford told OurAmazingPlanet.

Basically, Redford said, bison that are not raised for sale, but are left on their own in nature.

This goal is of mutual interest to the seemingly strange bedfellows that belong to the ABS — conservationists, bison ranchers, scientists, government representatives and American Indian tribal leaders.

"We all love bison, and we're all in favor of increasing the bison in the herds across the country," said Dave Carter, head of the National Bison Association, an industry group for private bison ranchers.

Carter acknowledged that although some in the private ranching community look askance at efforts to team up with conservationists, he said increasing so-called "conservation herds" on public lands is in everybody's best interest.

In the United States today, there are roughly a dozen such conservation herds, managed for the most part by the Department of the Interior, of about 20,000 animals in total.

There have been efforts to list the bison as an endangered species, but in February, the U.S. Fish and Wildlife service, after a lengthy review process, declined to do so.

"One of the justifications to deny that petition is that the conservation herds in the U.S. are stable or increasing," Carter said. "So if we can help those herds grow we see that as a good thing."

Champion of the grasslands

For people like Redford, returning bison to the United States' open grasslands is just one large piece of an even larger conservation puzzle.

"If bison were managed with fire in large enough areas, it is our belief that there would be the restoration of many other species and ecological processes that used to typify the grasslands of the United States," Redford said.

Where bison roam, Redford explained, soon follow a host of other species that formerly lived on the prairie, from plants to birds to wolves — even grizzly bears.

"Our association of grizzlies and wolves with mountains isn't because they prefer mountains, but because that's the only place they were allowed to survive," Redford said.

Muddy genes

Redford said the ABS is facing three main challenges. First, bison occupy a murky status according to state and federal laws — as livestock and wildlife — and Redford said their legal standing needs to be clarified.

Second, is the challenge of brucellosis (B. abortus), a bacterial disease with a nasty name and effect that originated in cattle, and made the rounds to other ungulates like bison and elk. The disease is largely controlled, but some livestock producers fear infection from wild bison, a claim that lacks solid evidence.

Finally, there is the matter of bison genetics.

The latter issue is a big focus of this year's meeting. Most bison, it turns out, are genetically mixed: mostly bison, but with a little bit of cow lurking around the genome.

Back when bison were nearly exterminated, in the 1890s and 1900s, a few creative ranchers got the idea to breed them with cattle. Bison are extremely hardy, and the idea was to create a kind of super-hybrid that could survive temperature extremes and diseases, a quality that would make the animals extremely profitable.

The practice was quickly abandoned — "You get a female cow with a bad attitude and a bull that is sterile," Carter said — yet since today's bison all come from such a few animals, those cattle genes have stayed in the mix.

In addition, technology doesn't allow for efficient testing of animals. When looking at bison DNA, scientists only look at a certain strip of the animal's long genetic code, and it could be that cattle genes are hiding out in another, unexamined region of the genome.

The only genetically "pure" bison left are the roughly 3,000 animals that live in Yellowstone National Park.

Some argue that only the "purest" bison should be put in conservation herds. It is a confounding problem, given the difficulty of determining a given animal's "bison-ness."

Redford says that, although retaining the best genetic representation is important, the issue shouldn't halt moves to increase conservation herds.

Pointing to the recent discovery that Neanderthal genes lurk in our own genome, Redford said, "It happened a long time ago in human genetic history, and we don't understand ourselves as any less human."

In addition to the practical benefits wild bison offer, Redford said that in the end, the iconic species offers something less tangible yet equally important — especially given the animal's near disappearance and dramatic rescue, it has always loomed large in the American consciousness.

"When people are given the chance to see wild bison," Redford said, "they find a way to connect to the natural world."

And perhaps to each other. "Nobody texts when they're in the company of wild bison," Redford said.

Andrea Mustain is a staff writer for OurAmazingPlanet, a sister site to LiveScience. Reach her at amustain@techmedianetwork.com. Follow her on Twitter @AndreaMustain.

Something strange happens when it rains in Kruger National Park in South Africa: Buffalo mothers give birth to more sons. Now, scientists think they know why — it's in their genes.

The results from a new study suggest that certain genes in male buffalos distort the genetic material in their sperm so that they father only sons. And these genes are "turned on" when there's plenty of grass to chow down on, as happens during the rainy season.

However, there appears to be a few systems in play so that overall, the proportion of males to females tends to even out. For one thing, the males with these sex-distorting genes are usually less fertile than other males. Another possibility is that a different set of genes, triggered by the dry season, influence the resulting brood so that there's slightly more females.

If true, the findings would be the first evidence of so-called sex-ratio genes in large mammals. These genes have so far only been observed in insects, such as files, and in rodents.

The findings suggest that sex-ratio genes might be present in more animals than scientists have suspected, and perhaps even in humans, according to study researcher Pim van Hooft of Wageningen University in The Netherlands.

 "I think it's not unique for the buffalo," van Hooft said.

Sex genes

Sex-ratio genes are located on the chromosomes that determine an animal's gender. Chromosomes are packets of DNA inside a cell's nucleus. In buffalo and people, one pair of chromosomes, called the X and Y chromosomes, are considered sex chromosomes.

Each parent provides one sex chromosome to the offspring, with males giving either an X or Y and females giving only X chromosomes. Offspring with XX become female and those with XY become males.

Sex-ratio genes are malicious, however. They work by either killing or disabling the opposite sex chromosome. So if they are lurking on the Y chromosome, they kill off the X, meaning the father's sperm will contain only Y chromosomes, so he'll only produce male offspring. And if they're on the X chromosome, the opposite happens. Sex-ratio genes are thought to carry out their attack during spermatogenesis, or the formation of male sperm.

"Because the males have a distorted sex-ratio [gene] in their sperm, you get a distorted sex ratio at birth," van Hooft said.

Too much diversity

Van Hooft examined blood samples collected from buffalo during 1998. Because the samples included the age of the animal, he was able to go back in time, looking at the genetics of buffalo that varied in ages from 0 to 15 years.

What he found was quite strange. The amount of genetic variation on the Y chromosome was surprisingly different between buffalo of different ages, even if they were only a year apart. It was as if there were two different types of Y chromosomes, and the ratio of these Y-chromosome types fluctuated from season to season, and also from year to year.  

Normally, you would expect buffalo that were so close together in age to have very similar Y chromosomes, van Hooft said. After all, it's the same parent generation producing the kids for quite a few years, and shifts in the population genetics just don't happen that fast.

He also saw that the number of males and females born during each season was slightly skewed. During the rainy season, the ratio of males to females was about 53-to-48, so if there were 100 buffalo babies born, 53 would be male and 48 female on average. The reverse was seen in the dry season, with relatively more females born.

Van Hooft reasoned that sex ratios were at play, and that they were triggered by environmental conditions, which in turn affected the sperm.

"Apparently, these sex-ratio genes are triggered by the body condition, or the semen quality," van Hooft told LiveScience.

Here's what could be happening:

Some sex-ratio genes are turned on by the wet season, causing some male buffalo in the population to produce only sons. This increases the proportion of males in the population, and the Y chromosomes from those males would be overrepresented.

During the dry season, a different set of sex-ratio genes could be turned on, ones that had the opposite effect. The final result is an increase in females, along with a fluctuation in Y chromosome types.

Since these genetic influences on the whole balance out, it means that scientists could easily miss the presence of these sex-ratio genes unless they look at the actual variation in the genes of a population.

Van Hooft thinks it's possible that we could even find such genes in humans, since some studies show a seasonal variation in sex ratio in certain populations, he said.

"They have difficulty figuring out how to explain this [seasonal variation] pattern" van Hooft said. "My study indicates, maybe these seasonal variations are also the result of some sex ratio genes, only we did not look at it yet, for such effects."

The results are published in April 23 in the journal BMC Evolutionary Biology.

• Top 10 Surprising Sex Discoveries
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Africa is home to spectacular migration events. Large mammals ranging from Grant's gazelles to blue wildebeests pound their hooves across vast tracts of land as the seasons change.

New research suggests, however, that migrations across the continent might be going extinct.

For the first time, scientists have compiled and analyzed data on all of the world's largest and definitive migrating land mammals. The researchers looked at the migration history for a group of ungulates, all of them hoofed mammals, weighing more than 44 pounds (20 kg). The data suggest that one-quarter of these mammals no longer migrate, and human development is responsible for the decline, said Grant Harris, co-author of the study.

In many cases, data on these animals is simply nonexistent.

"I thought, 'Oh my gosh, there's nothing here at all,' and if there's nothing here for these large mammals, this bodes poorly for other species," Harris told LiveScience.

Harris, a conservation biologist, conducted the research while with the Center for Biodiversity and Conservation at the American Museum of Natural History in New York. He is now at the U.S. Fish and Wildlife Service in Albuquerque, N.M. The report was published in the April edition of the journal Endangered Species Research.

Some already done

Large mammals such as the wildebeest or bison depend on green vegetation, like grass, for survival. They live in herds that are too large to depend on a single location for food, so as the seasons change, and rainfall drifts or snow melts, new vegetation grows and the herd tracks these flourishes. But these patterns are unpredictable, so migrations rarely follow a set path, leaving some migrations unnoticed by even experienced researchers.

To understand more about the current status of migrations, Harris and his colleagues focused on population numbers, migration history and known threats for 24 migratory ungulates — 14 in Africa, 7 in Eurasia and 4 North America, (the caribou/reindeer Rangifer tarandus is found in both Eurasia and North America).

The researchers found that for six of these species — the springbok, black wildebeest, blesbok, kulan, scimitar horned oryx and quagga (extinct) — mass migrations either no longer occur, their current status is unknown, or the species is recently extinct.

Africa is home to five of the six mammals that no longer migrate.

What's wrong

Most populations lack basic data such as herd numbers, migration distance or routes traveled, and many reports are over a decade old. The new study provides a framework to guide future conservation efforts as scientists fill in the gaps and devise strategies to preserve migrations, which are sometimes not as obvious as a herd of wildebeest, said Stuart Pimm, a conservation biologist at Duke University who was not involved with the study.

Threats are listed for 20 mass migrants in previous studies. Hunting or poaching is listed as a threat for 17. Most animals migrate across national and park borders, where fencing or roads can block access to food or water. Some conservationists have advocated placing migrating species within parks, but because migrations can extend beyond park boundaries, agricultural and other types of development on the periphery can cut off food and water access. Parks themselves are also fenced, which blocks migration and confines species. This can then aid poachers.

A one-size-fits-all solution for protecting migrations doesn't exist, Pimm said. With so little research on the animals themselves, even less has focused on conservation. But most scientists think it boils down to filling in data on migrations and then finding a way for humans to develop landscapes in a way that has a gentler impact on wildlife. "You can't even think about solutions if you haven't thought about the problems," Pimm said.

• Video: Massive African Wildlife Migration
• Evolution's Most Extreme Mammals
• Top 10 Incredible Animal Journeys

Bison with the loudest bellows lose out in the mating game, while the quietest bulls score the most mates and sire the most offspring.

"We were expecting to find that the bigger, stronger guys — the high-quality males — would have the loudest bellows, because they can handle the costs of it," said Megan Wyman, a graduate student in geography at University of California, Davis and the lead author of the study. "But instead, we found the opposite.

Wyman and colleagues also found that the volume of a bison bull's bellow was not related to its weight or age.

American bison are not buffalo. But these icons of America are prone to homosexual behavior. More than 55 percent of mounting in young males is with the same gender. Meanwhile, they eventually do get the job of procreation done during the annual rut.

Wyman and Michael S. Mooring of Point Loma Nazarene University and a number of student interns spent two summers monitoring the mountings and other activity of 325 wild bison in Fort Niobrara National Wildlife Refuge in the Sandhills region of north-central Nebraska.

Quiet dominance

The reason a soft touch works is not clear, but it could be the bulls want to keep it down so other males don't horn in on their activity.

Bison bellows are loud, low-frequency vocalizations performed by bulls during the rut. They are most commonly used when one male challenges another, typically when the two are within 45 to 90 feet of one another. Yet sometimes a bellow will attract bulls from further away, and this may be one reason that a herd's dominant bulls keep their voices down, Wyman speculates.

"It could be that bulls provide information about their high quality through other signals — for example, the frequency or the duration of their bellows. So they don't have to be louder, they just have to be heard," she said. "If you bellow too loudly, it could bring in too many other bison to check you out."

Wyman wonders why lower-quality males don't turn down the volume of their bellows to emulate their more successful rivals.

"That's a lot harder to explain," she said. "It could be that if you use a quieter volume, other bulls have to approach even closer to check you out, and any time you bring someone that close, there's a higher risk of attack. And that's the type of cost that these low-ranking bulls may not be able to bear."

Watching the rut

Bison once numbered in the tens of millions across the continent, but they were wiped out by commercial hunting and habitat loss. By 1889, fewer than 1,100 individuals remained. Some 500,000 exist today, but only about 20,000 are wild; one conservation group says they could be poised for a big comeback.

Observing the herd for 14 hours each day during the two-month rut of July and August, the researchers recorded each copulation and to detail the tangled web of connections between males and females as bulls lost and gained cows during their intense competitions. To assess where each bull ranked in the herd's hierarchy of dominance, Wyman tallied outcomes of challenges between rivals, including threats that ended with an animal backing down in the face of combat, as well as full-blown, head-to-head fights.

When calves were born the following spring, DNA samples were taken to determine parentage.

For measurements of amplitude, Wyman used a hand-held sound-level meter from the safety of her vehicle. With each reading, she also recorded specific behaviors of the bull, his female and any challenging rivals, as well as noting the factors that could affect the level of the reading such as the bull's head orientation, its distance from the meter and wind conditions.

Her analysis showed that, on average, the least successful bulls — those with the lowest number of copulations and offspring — bellowed at least 50 percent louder than their more successful rivals, corresponding to decibel readings averaging from 109 per bull down to 103. This drop in volume correlated with a rise in the number of times a bull copulated from none to five, and the number of calves it sired from none to nine.

The findings were detailed in the November issue of the journal Animal Behaviour.

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• Bison vs. Buffalo: What's the Difference?
• Bison: It's What's For Dinner

The bones of wolves could provide a better record than tree rings of environmental changes in Earth’s climate, a new study shows.

Reliable human records of Earth's climate only extend back for a hundred years or so, therefore scientists also rely on other methods, such as tree rings and air bubbles trapped in glacial ice, to look for trends in the changes in the composition of Earth's atmosphere.

But these sources also have "noise" problems due to natural variability and random events that affect the chemistry of the atmosphere.

Bones less noisy

Seeking to compare alternative approaches, scientists at Michigan Technological University speculated that the bones of certain predators would reveal the same trends in atmospheric changes without picking up the same noise because carnivores often sit at or near the top of food chains.

"Wolves consume many prey animals—a minimum of 150 to 200 moose contribute to an Isle Royale wolf's diet over the course of its lifetime—and the prey consume a whole lot of plants," said study leader Joseph Bump, a graduate student at Michigan Tech. "Just by being who they are, wolves and other top predators increase the sample size, because they do the sampling for us."

The chemical fingerprint of climate change, in bones and other substances, results from the change in the ratio of carbon-12 and its isotope carbon-13 that occurs from the burning of fossil fuels. Carbon-12 is always more abundant in the atmosphere, but it increases relative to its isotope from fossil fuels, so more has accumulated in organisms in recent years.

Bump and his colleagues studied the bones of moose and wolves to see how the carbon ratio has changed over time. Some of the bones date to 1958 and were taken from Isle Royale National Park on Lake Superior. The researchers also looked at 30,000-year-old bones from the extinct dire wolf, collected from the La Brea Tar Pits in Los Angeles.

The results of the study, funded by the National Science Foundation, the Environtmental Protection Agency, then National Park Service and Earthwatch, are detailed in the Aug. 7 online edition of the journal Proceedings of the Royal Society-B.

Clearer fingerprint

The wolf bones from both sites provided a much clearer record of environmental change than either bones take from the moose and bison or from plants.

"Since the widespread combustion of fossil fuels, we have put a human fingerprint on atmospheric carbon dioxide," Bump said. "That fingerprint shows up in trees, and it shows up in animals that eat trees, but it shows up with the least variation in the top predators."

Bump hopes that this new line of evidence will help scientists establish a firmer climate record, since the bones of predators dating back hundreds of thousands of years are available in museums worldwide.

"Instrumental records of environmental variables are only available for about the past few hundred years so this may help us understand paleo-environmental change better," Bump said. "And if we can understand ancient environments better, then our ability to predict future change is improved."

• What's Your Environmental Footprint?
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• Images: Glaciers Before and After

Some animals forget to fear longstanding predators if these enemies do not hunt them constantly, a new study finds.

In particular, moose, caribou, bison and elk fear predators only if they encounter them regularly, according to a study by Joel Berger of the Wildlife Conservation Society (WCS) in New York.

However, Berger also found that the prey animals could "relearn" their fears very quickly, which should be good news for programs attempting to reintroduce predator species into their natural habitats. It means prey populations might plummet intially when a predator appears again after a lengthy absence, but they will reach equilibrium again shortly after.

Berger's findings are detailed in the latest issue of the journal Conservation Biology.

Short memory

The 10-year study took Berger all around the world. He traveled to polar islands of Greenland, the Arctic archipelago of Svalbard, and Norway, where wolves, tigers and brown bears—the natural predators of the ungulates studied—no longer exist. He went also to Yellowstone and Grand Teton National Parks, where these same predators have been re-established after periods of absence.

In each location, Berger played recordings of howling by wolves and heavy breathing by tigers and recorded the reactions of the prey. For controls, Berger did the same thing for prey animals living in Eastern Siberia, Boreal Canada and Alaska, where the predators are still found.

Animals living in locations where the predators no longer existed exhibited lower levels of vigilance, clustering behavior and flight responses than their counterparts living under constant threat of being hunted.

Elk in the mountains of Siberia, for example, which coexist with tigers, wolves and bears, responded five times faster to the recordings than did elk in Colorado’s Rocky Mountain National Park, where elks' top predators have been absent for about 90 years.

The prey animals were also exposed to recordings of calls made by howler monkeys, whose vocalizations vary in frequency and therefore sound like howling wolves. The prey animals, even those actively hunted by wolves, largely ignored the monkey calls, indicating they were capable of distinguishing between sounds made by known threats and other sources.

Berger’s study also found that prey animals can relearn their fear in a single generation. Reactions by bison to the predator calls in Yellowstone National Park—where grey wolves were reintroduced in 1995 after a nearly 70-year absence—even exceeded those of bison in Boreal Canada, where wolves are still naturally found.

Conservation implications

Berger expects his findings will come as welcome news for those trying to reintroduce predator species back into their natural environments after years of absence. “It’s good news [for] northern temperate and arctic fauna that they figure it out pretty fast,” Berger told LiveScience. “Because initially they may get hit hard, but they will learn.”

Berger recalls that when grey wolves were reintroduced into Yellowstone, “some people said ‘Ten years from now, we will not have elk.’ Well, there’s still a lot of elk there. The same is true for Wyoming.”

Ecosystems where the top predators are wiped out can suffer from overgrazing by prey species, which are no longer kept in check. But “if prey species become afraid, they tend to move around more and not concentrate on vegetation in certain areas,” Berger said in a telephone interview. “There’s a release, the vegetation is given a reprieve, and all the species that rely on vegetation, like migratory birds, do better when these large carnivores are back in the system.”

But allowing predator species to repatriate their natural environments is not enough, Berger said. They must also be allowed to breed, so their populations grow large enough that their presence is felt once again.

This is one of the major problems programs trying to re-establish natural predator species currently face. Berger’s findings come at a time when, after more than $23 million was spent to re-introduce wolves in the northern Rocky Mountains, the animals' federal protection is set to expire. The states of Wyoming and Idaho have already proposed plans that would allow for as much as 85 percent of these once-protected wolves to be killed, according to the WCS.

“There’s a density effect,” Berger said. “If you have just a few wolves that are put into a system, they’re still far below what the number should be when the system is balanced. They’re unlikely to create this effect where the species are moving about.”

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Bison poop has more to offer than a field-clearing smell. Genetic analysis of the feces has revealed there are two breeding populations of bison in Yellowstone National Park, according to a new study.

The discovery has implications for how to manage the roughly 4,000 bison (called Bison bison by scientists), which were previously considered one giant breeding population within the park's boundaries.

“It takes crazy people like us to go out in the field and pick up poop from bison,” said lead scientist Flo Gardipee, a graduate student at the University of Montana. “But now we are getting some really important information regarding bison ecology out of it.”

Which is Which?

While the study results are still preliminary and require further testing, Gardipee said having two breeding populations could help boost the overall genetic diversity of the bison [image].

• Bison vs. Buffalo: What's the Difference?

The scoop on poop

Until now, scientists have relied on blood and tissue samples to extract DNA from bison. These methods involve handling the animals—which can weigh up to 2,000 pounds—and the use of tranquilizers in doses that are lethal to humans.

The poop-scooping method is less invasive. “We don’t have to round them up, rough them up or manhandle them in any way,” Gardipee said.

Gardipee and her assistant sampled poop from bison herds in Grand Teton, as well as from groups in Yellowstone’s Hayden Valley, Lamar Valley and Mirror Plateau. The scientists waited for one of the more than 100 bison to defecate. When the poop plopped and the animal wandered away, Gardipee went in to retrieve the sample. The animals didn’t always cooperate.

“Every now and then we have some fairly self-determined bison that just won’t move, and we end up not getting the sample,” Gardipee told LiveScience.

Cell extractor

The poop itself doesn’t contain the DNA. When a bison chows down, the roughage scoots through the digestive tract before a less-recognizable chunk of it passes out of the gut. During the descent, cells lining the gut slough off and hitch a ride with the feces.

Gardipee looked at the transported gut cells and found DNA from mitochondria, the cells’ energy-making structures. This genetic material comes from females, so it can trace maternal lineages and, in this case, give information about breeding groups in bison.

If females were to plod back and forth between different groups of bison, the animals would all show similar mitochondrial DNA.

• All About DNA

Instead, Gardipee found stark differences in the maternal DNA. In Hayden Valley, where 2,000 bison reside, and in Grand Teton, she found only one maternal line called haplotype 6. In Lamar Valley and Mirror Plateau, the more than 900 bison showed a different mix of mitochondrial DNA.

“This shows there is potentially a minimum of two different breeding groups in Yellowstone,” Gardipee said.

Rich history

Tens of millions of the seemingly-ungroomed goliaths once roamed expanses of North America. In the 1800s, human settlers are thought to have hunted the bison to near extinction, with one report estimating a mere 25 bison left in 1894. Currently, up to 500,000 bison exist, with 95 percent under private ownership on ranches.

Since the late 1800s, cattlemen have cross-bred bison with cattle, resulting in a large number of hybrid bison.

“There’s been research done that has found widespread hybridization of those private herds and of cattle,” Gardipee said.

Last year, about 900 bison were slaughtered after they wandered out of Yellowstone because of fears they would spread an infectious disease called brucellosis to native cattle.

“No one knows, of the 900 animals that were sent to slaughter, how many came from each breeding group," Gardipee said. "If one breeding group is being culled disproportionately from another, we can lose lineages there. We can lose overall genetic diversity in the entire Yellowstone population.”

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• VIDEO: Yellowstone

The bones of an extinct dwarf species of buffalo were recently unearthed on the Philippine island of Cebu.

Dubbed Bubalus cebuensis (BOO-buh-luhs seh-boo-EN-sis), the miniature buffalo [image] stood at just more than two feet, three times smaller than today's domestic buffalo, and weighed a mere 350 pounds. It probably lived during the Pleistocene (Ice Age) or Holocene Epochs, between 10,000 and 100,000 years ago.

"Natural selection can produce dramatic body-size changes. On islands where there is limited food and a small population, large mammals often evolve to much smaller size," said lead researcher Darin Croft of Case Western Reserve University in Ohio.

The finding, detailed in the October issue of the Journal of Mammalogy, is the first well-supported example of "island dwarfing" among cattle or their relatives and could have implications for the current debate about Homo floresiensis, a recently discovered hominid that some scientists say is a new dwarf species.

Sizing up

Fossils are rare in the tropical environments of the Philippines, a region lacking open rocky patches where fossils are often buried and preserved, and this is the first fossil mammal of any age reported from Cebu Island. The fossil remains were found 50 years ago in a phosphate mine by engineer Michael Armas. Nearly four decades later, he showed them to physician Hamilcar Intengan, who recognized their importance and brought them to The Field Museum for study in 1995.

Scientists, including paleontologist John Flynn of the American Museum of Natural History in New York, examined the partial skeleton, which included two teeth, two vertebrae, two upper arm bones, a foot bone [image] and two hoof bones. The species had relatively large teeth, which is typical of island dwarfs, but also relatively big feet, which are generally reduced along with other body features in dwarfing.

"The reason that might be is because evolution actually works in different ways--we call it mosaic evolution--that not all features change in exactly the same way all the time. For whatever reason, this particular species didn't reduce the foot proportions the same way that dwarfs of other species on other islands might have," Flynn told LiveScience.

Island survival

The finding supports the idea that the earliest water buffalo were large and first evolved in Southeast Asia. The animals likely traveled from the mainland to the Philippine islands when sea levels dropped roughly 400 feet during the peak of the "Ice Age" about 20,000 years ago.

Less food was available on the islands and the buffalos might have shrunk to compensate, Flynn said. That could be why this buffalo is smaller than two living related species--a domestic buffalo (Bubalus bubalis) and the tamaraw (Bubalus mindorensis).

The tamaraw is also a dwarf and lives only on the Philippine island of Mindoro. At about three feet tall at the shoulder and 500 pounds, it is much larger than the newly discovered species. The researchers speculate that the new dwarf buffalo was smaller than tamaraw because it roamed an even smaller island that had less food.

In combination with the tamaraw on Mindoro and a report of buffalo fossil teeth found on another Philippine island, Luzon, the new discovery indicates this genus might have once lived throughout the Philippines, most of which is an oceanic archipelago, never connected to any continental land mass.

Dwarf debate

The research could provide insights into debates on the evolution of small-bodied species elsewhere in the tropics such as the proposed new hominid, Homo floresiensis, found on the Indonesian island of Flores in 2003.

While Flynn doesn't have sufficient knowledge of the dwarf hominid, the new discovery does support the validity of dwarf island species in general--indirectly lending weight to the dwarf hominid. If a buffalo could shrink, why not a hominid?

"This discovery emphasizes that it's not all that uncommon to find dwarf species evolving on islands," Flynn said.

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• Dwarf Dinosaur Discovered
• Images: The World's Biggest Beasts      
• Newfound Reptile Swam in Dinosaur Era
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A tuberculosis pandemic among an ancient mammoth-like creature probably contributed to the great beasts' demise, a new study suggests.

Scientists examining mastodon skeletons found a type of bone damage in several of the animal's foot bones that is unique to sufferers of tuberculosis. The disease would have weakened and crippled the animals, making them more vulnerable to humans and climate change, two factors that scientists have long speculated were behind their extinction in North America.

Mastodons were ancient elephants that resembled mammoths, but were shorter and less hairy. Both species lived in North America and disappeared mysteriously, along with other large mammals, around the time of the last major Ice Age about 10,000 years ago.

A crippling disease

Researchers Bruce Rothschild of the Northeastern Ohio Universities College of Medicine and Richard Laub of the Buffalo Museum of Science in New York looked at 113 mastodon skeletons and found signs of tuberculosis in 59 of them. That's 52 percent.

Tuberculosis is a bacterial infection that commonly infects the lungs. It can also affect other parts of the body, including organs and bones. In humans, only about 1 to 7 percent of infected individuals develop bone damage. The fact that more than half of the mastodon skeletons examined had the bone lesions suggests tuberculosis was a "hyperdisease" that afflicted a large percentage of the North American mastodon population.

When tuberculosis infects bone, it creates a tell-tale type of damage in which bone beneath cartilage is carved out, or "excavated."

The infected mastodons were different ages and sizes and came from all over North America. They lived at different times, too. The disease appears to have struck the creatures as early as 34,000-years-ago and persisted in the species until as recently as 10,000- years-ago.

That the disease was widespread and yet persisted for so long in the species suggests it was not immediately lethal, Rothschild said. Instead, it was probably a chronic disease, one that gradually weakened rather than killed the animals.

Mastadon stressors

In humans, tuberculosis can lay dormant for several years after initial infection, repressed by the body's own immune system. But it can flare up into full-blown disease during times of stress. A similar flare-up probably happened with the mastodons during times of stress, Rothschild said.

Mastadons living at the end of the last Ice Age had reasons to be stressed. They faced not only a drastically changing world brought about by rapid climate change, but also the arrival of a new threat: weapon-wielding humans that hunted them for food.

Together, these three factors—disease, climate change and humans—might have been too much for the creatures. Weakened by tuberculosis, the beasts would have been less able to ward off other diseases, and the crippling bone damage would have affected their ability to walk.

"Extinction is usually not a one-phenomenon event," Rothschild told LiveScience.

A route of infection

But how did North American mastodons first get tuberculosis, a disease whose first known documentation is in a 500,000-year-old buffalo in China?

Rothschild thinks he knows the answer. In a separate study, he and Larry Martin from the Natural History Museum in Kansas found similar tuberculosis-caused bone damage in North American bovids, a group of animals that included bison, musk oxen and bighorn sheep.

Tuberculosis appears to have been just as prevalent in the bovids as in the mastodons, but the record of infection for this group of animals stretches back much further—at least 75,000 years.

Bison and other bovids are believed to have originated in Asia and crossed into North America using the Bering Land Bridge, which connected the two continents. Humans made the same journey much later.

The researchers speculate that some of the bovids were probably already infected with tuberculosis when they migrated into the New World. Once in North America, the bovids could have spread to mastodons and other species, possibly even humans, Rothschild said.

Both the mastodon and bovid studies will be detailed in upcoming issues of the science journal Naturwissenchaften.

• Images: The World's Biggest Beasts
• Scientists Aim to Revive the Woolly Mammoth
• Climate Change, Not Humans, Killed Large Beasts
• Giant Creatures Wiped Out by Hunters, Not Climate
• Pleistocene Park Could Solve Mystery of Mammoth's Extinction
• More Drug-Resistant TB Seen in U.S.

Good news for wildlife

The success stories of the bald eagle, American alligator, and blue poison frog give species on the brink of extinction something to live for. LiveScience takes a close look at the most impressive comeback kids.

Bald Eagle

In February, the U.S. Fish and Wildlife Service announced it could safely consider kicking our country's national symbol off the federal Endangered Species List. Survivors of the banned poison DDT, the eagles' numbers soared from 417 nesting pairs in 1963 to 9,250 nesting pairs today.

Bison

More than 50 million bison roamed the North American prairies before cowboys headed West and hunted the population down to as few as 750 animals. In 1905, the American Bison Society conserved land for herds and introduced captively bred individuals whose descendants now number about 350,000.

California Condor

The California condor's not winning any beauty pageants, but its rise from the ashes earns the largest North American bird a Top 10 spot. Its 1987 extinction in the wild make today's 125 free-flying birds a remarkable tale of nurture and nature.

Black-footed ferret

Proclaimed extinct prematurely, the last 120 feral ferrets were discovered in 1981 after a Wyoming farm dog brought one home in its mouth. A decade later, a triumphant captive breeding program has released 2,300 ferrets into the wild.

Koala

Hunted to near extinction for its fur in the early 20th century, native Australian koalas are thriving in protective reserves. In fact, isolated populations and those on predator-free islands have reached pesky plague proportions.

Grizzly Bear

Protection on the Endangered Species List is ending for the grizzlies. About 600 bears live near Yellowstone, up from 271 left in 1975. Populations are in such great shape, say experts some states, that they could become open game for hunting season.

Blue poison frog

Its flashy looks made this small-town frog a top-selling trinket in the international pet trade. The frog leaped back from near extinction with protection from collectors, captive breeding, and conservation of its little habitat in Suriname.

Goliath grouper

As the biggest fish in the coral reef at 700 pounds, fishermen have coveted a Goliath catch, forcing its population to crash in just 30 years. A 1990's fishing ban in the Caribbean has helped southern Floridian grouper youngsters rebound.

South African dragonflies

An invasion of nonnative eucalyptus trees blocked the sun shining on the South African habitat that dragonflies depend on. A national program to cut down the shady trees has brought light to the insects, and jobs to local people.

American alligator

Hunting quotas and egg collection programs cracked the gator decline in the southeastern United States. Landowners collect eggs, when alligators are most vulnerable to predators, sell some of them to gator ranchers, and return the rest of the hatch to the wetlands.

Failure to adapt to a drastically changing climate, and not overkill by humans or disease, most likely lead to the extinction of mammoths, wild horses, and other large mammals after the last Ice Age, a new study suggests.

But this fresh take on an old argument might not be the final word.

Dale Guthrie of the University of Alaska has added 600 radiocarbon-dated fossils to the established collection, and his examination reveals that mammoths and wild horses were in serious decline before humans arrived on the scene in Alaska and the Yukon Territory.

Like the end of the dinosaurs, the topic of large mammal extinctions is a hot one. While the new results might be true of the far North, some researchers still believe over-hunting contributed to the demise of the beasts across the rest of the continent.

The study, which also analyzed the fossil record of bison, elk, moose, and humans in the far North between 18,000 and 9,000 years ago, is published in the May 11th issue of the journal Nature.

Pushed to the brink

It's generally accepted that humans first entered North America from Siberia around 12,000 years ago. Since mammoths and wild horses became extinct roughly 11,500 and 12,500 years ago, some scientists have figured that hungry humans might have hunted them into oblivion.

"The old idea, that I once had, was that these animals were killed off and then the modern large mammals expanded and took their place," Guthrie said.

According to Guthrie's new data, however, bison and elk populations were doing well during this period, and those species had expanded dramatically long before other species went extinct. So why weren't bison and elk over-hunted to extinction as well? Interestingly, the fossil record shows the two beasts were hunted more vigorously, yet they endured.

"I imagine humans were hunting anything they could get," Guthrie said. "Horse meat is probably just as tasty as bison. But their campsites don’t show many mammoth and horse remains—they're full of bison and elk."

Guthrie's interpretation of the fossil record is that something else pushed mammoths and horses to the brink, and if humans did play a role in the extinctions, it was limited to just killing stragglers.

The fossil record also casts doubt on the possibility of a mega-disease that wiped out animals across the board, Guthrie said. A deadly disease would create a distinct end for each species, which isn't reflected in the fossils. Also, diseases that infect and kill multiple species are extremely rare, and unlikely in this case since bison, elk, and moose weren't affected.

So what happened up North?

The period between 13,000 and 11,000 years ago was a great transitional time for the far North. Although scientists don't know exactly what happened during this period, they can tell certain things from the geologic and fossil record.

"We know that animals' body size changed, there was a mass extinction, temperature changes, and humans came in," Guthrie said. "A lot of animals, such as bison, didn't do real well before that time. Then they really prospered for a while and didn't do real well after that."

Before 13,000 years ago, the food available in the region was mostly short, dry grass of little nutritional value, Guthrie said. Then, as the Alaska and the Yukon warmed up, and water returned to the land, the dry grass was replaced with tall lush grass and bush—the type of plants grazers like elk and bison prosper on.

"Long before horses and mammoths became extinct, bison and elk began to expand," Guthrie said. "The only good way to account for that expansion would be the availability of a more abundant and nutritious food source."

But as the region continued to warm and received more rain, the plants kept growing. Boreal forest—which includes inedible trees such as pine, spruce, and birch—began sprouting and limited the amount of grassy areas for grazing. Bison and elk populations decreased with this transformation, but, Guthrie said, they adapted to the habitat change and out-competed mammoths and horses for the remaining food.

"Humans were probably hunting some of the animals that went extinct, but 1,000 years after humans came in, [bison and elk] were still doing fine," Guthrie said.

Continental overkill?

David Steadman, a researcher at the University of Florida who believes humans drove the giant sloth to extinction, agrees that encroaching boreal forest may have been the end for large mammals in the North. But what about across the rest of the continent?

"It's a great piece of evidence—I don't doubt it; I trust his data," Steadman told LiveScience. "What happened in Alaska and the Yukon is swell, but why did these things die out in Texas and Mexico and Arizona and Florida?"

Like many researchers in the field, Steadman attributes a combination of factors to the extinction of these beasts. But he believes humans, and not climate, played the leading role throughout the New World.

"There are so many things going on, and to me it's illogical to think that warming up and getting rid of ice sheets at 40 degrees latitude is a bad thing for large mammals," Steadman said. "They went through 20 glacial cycles in the last million years, and got through every one except for the last one. It has a certain odor to it, and that odor is of humans."

Previous articles on this controversial topic:

• Prehistoric Humans Wiped Out Elephants
• Humans Might Have Wiped Out Wild Horses
• Scientists Aim to Revive the Woolly Mammoth
• Giant Creatures Wiped Out by Hunters, Not Climate