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 ...

A new study challenges long-held ideas about why ammonites vanished while nautiloids survived the end-Cretaceous extinction. Researchers found that the few ammonite species that briefly persisted had ...

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

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

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

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

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

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

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

Discover North America's biggest birds by wingspan, height, and weight, and learn about extinct giants like moas.