Charles Choi

"If there are lots of black holes out there, some of them must surely pass through our backyard every now and then."

Why are dogs, especially puppies, in endless pursuit of their tails?

Will the East African Rift split the continent and create a new ocean, or will it fizzle out?

The eruption was the most powerful natural explosion in over a century, triggering a tsunami hundreds of feet high.

Dogs commonly tilt their heads, but is it a sign of intelligence, or does it mean something else entirely?

The average life expectancy of a dog is more than 10 years, but life span varies greatly among different breeds.

The deadly toxin can be difficult to detect.

This is what sets us apart from the rest of the animal kingdom.

A new study of human DNA -- and the largest genetics study yet of ancient peoples -- reveals that the Paleo-Eskimos are genetically distinct from both the Neo-Eskimos and modern Native Americans.

Unusual fish that walk and breathe air turn out quite differently when raised on land, rather than in water. Their development holds clues to a pivotal moment in animal evolution, when the first creat