Earth looked much different not just millions, but even decades and centuries ago. Many animal species that once existed are nowhere to be found. From human activity to climate change, new animals ...

BILLINGS, Mont. — Death has come knocking one last time for the splendid ivory-billed woodpecker and almost two dozen other birds, fish and other species — the U.S. government is declaring them ...

Colossal Laboratories & Biosciences, which has produced a trio of modern-day dire wolves and the woolly mouse, seeks to bring back extinct species.

This year, at least six animal and insect species moved to the Extinct category of the IUCN Red List of Threatened Species Kelli Bender is the Pets Editor at PEOPLE. She has been working at PEOPLE ...