In a Harvard talk following a preview of his new documentary, the director debates nuclear energy's merits as a climate change solution.

"The fact that these tools are associated with Paranthropus may force us to rethink the capabilities of these enigmatic hominins."

"The fact that these tools are associated with Paranthropus may force us to rethink the capabilities of these enigmatic hominins."

The remains of a mother mammoth and her calf discovered in New Mexico is among the best evidence for humans settling in North America earlier than thought.

A new study doubles the age of ancient DNA in sub-Saharan Africa, revealing how people moved, mingled and had children together over the last 50,000 years.

New research that indicates humans may have arrived in Europe much earlier than previously thought also raises some intriguing questions.

Stone artifacts and a fossil tooth point to Homo sapiens living at Grotte Mandrin 54,000 years ago, at a time when Neanderthals were still living in Europe.

The stone age saw a pattern where technologies like spears, fire and bows were invented once, then spread