Add Yahoo as a preferred source to see more of our stories on Google. FILE PHOTO: A baby mountain gorilla rides on her mother's back on the slopes of Mount Mikeno in the Virunga National Park, Eastern ...

Humans have many wonderful qualities, but we lack something that’s a common feature among most animals with backbones: a tail. Exactly why that is has been something of a mystery. Tails are useful for ...

WASHINGTON, Feb 28 (Reuters) - Director James Cameron's "Avatar" movies are populated by a species of outsized blue beings resembling humans, except with tails. So why does our species lack a tail, ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Humans have many ...