Learn how egg size may help explain why ammonites didn’t survive the end-Cretaceous extinction 66 million years ago, while ...

Some of the most beautiful creatures to grace the ancient seas, the ammonites, disappeared in the end-Cretaceous mass ...

For 350 million years, ammonites were the resilient masterpieces of the ancient seas. They survived the Great Dying of the ...

Learn what the Endangered Species Act does, how it protects wildlife in the US and abroad, and why proposed changes could ...

Brain size can matter across the broad sweep of primate evolution but among humans isn't the best way to estimate ...

The company behind the dire wolf comeback hopes to restore Africa's bluebuck, once hunted to extinction by colonialists.

Exactly how did birds evolve from dinosaurs? It’s a mystery that has been with us for more than 150 years, and ...

Seventy-five million years ago, a Cimolodon desosai lived in the waning days of the Cretaceous period. While dinosaurs ruled ...

Earth's food webs suffer when giant animals go extinct, even 10,000 years later.

Mammals and dinosaurs coexisted on Earth until a catastrophic event 66 million years ago killed 75% of life on the planet.

Q. I am pretty sure that ostriches are the biggest birds in the world. But what is the biggest bird in North America?