There are millions of different types of living things on Earth. In order to keep track of them all, scientists put living things into groups based on characteristics that they have that are the same.

Sir David Attenborough at the Beijing Museum of Natural History with fossil of Juramaia, as featured in the Smithsonian Channel series Rise of Animals: Triumph of the Vertebrates. Famed British ...

Famed British broadcaster and naturalist Sir David Attenborough has been lending his calming voice to nature documentaries ever since TV was in black and white. And the 89-year-old is still at it. His ...