Scientists recently unearthed stunning fossils of sturgeon from Hell's Creek that might have died on the day that the dinosaur-killing asteroid struck.
The Cretaceous, the last and longest period of the dinosaur age, lasted from about 145.5 million to about 65.5 million years ago. During the Cretaceous, mammals were small, about rat size, and the land was ruled by dinosaurs, including the duck-bills (hadrosaurs), horned dinosaurs (Triceratops), long-neck sauropods (Dreadnoughtus) and the tyrannosaurs (Tyrannosaurus rex). When the 79-million-year-long period ended, largely because of a 6-mile-wide (10 kilometers) asteroid slamming into the Yucatan Peninsula, about 80 percent of all animal species went extinct, including the non-avian dinosaurs.
The Cretaceous period lasted approximately 79 million years, and ended with a major extinction event about 66 million years ago.
Scientists recently discovered fossils in Argentina that belong to Thanatosdrakon. The specimens are the largest pterosaurs ever found in South America.
Around 66 million years ago, springtime in the Northern Hemisphere brought disaster and mass death to Earth in the form of a giant asteroid impact that triggered a global extinction.
After an asteroid struck at the end of the Cretaceous period, debris from wildfires filled the atmosphere and blocked sunlight across Earth, causing ecosystem collapse and extinctions.
A newly described species of mosasaur, an extinct marine reptile, swam through Cretaceous seas 80 million years ago and had a slender snout like a crocodile's.
The largest triceratops in the world, scheduled to be auctioned on Oct. 21, will be on display to the public in Paris beginning Sept. 16.
A pterosaur "dragon" that lived in Australia during the Cretaceous was the continent's biggest flying reptile, according to a new analysis of a fossil jawbone.
A tiny amber-locked skull that looks like a bird's is actually a lizard's, new fossil evidence shows.
New simulations calculated T. rex speed from the motion of its swaying tail, finding that the massive dinosaur was a mighty slow walker.
Mosasaurus was one of the largest members of the mosasaur family, which were the top predators in the oceans during the age of dinosaurs.
Around 120 million years ago, tarantulas first appeared on the Gondwana supercontinent in what is now the Americas, and then dispersed into Africa, Australia and India.
New analysis of the ancient crocodylian Deinosuchus confirms that this apex predator had jaws and teeth that were powerful enough to subdue massive dinosaur prey.
The death strike of a Cretaceous "hell ant" from 99 million years ago is preserved in amber, revealing how these demonic-looking ants hunted.
Buckyballs are geometric shapes previously only seen in nature at the molecular scale. Scientists recently found them in marine animals dating to the Cretaceous.
Cryodrakon boreas, a newly described species of giant pterosaur, was recently identified from fossils found in Canada.
Paleontologists have discovered the remains of an ancient Loch Ness Monster look-alike in freezing Antarctica. And just like the legendary Nessie, it wasn't the runt of the litter.