There were thousands of years that Neanderthals and Homo sapiens inhabited the same regions in Europe. How much did these groups intermingle?

This video presents a reporter's visit to the Great Ape Trust, where apes communicate with researchers with a lexigram. But is this really language?

How can we preserve prehistoric artworks like those in southern France's Lascaux caves while still allowing modern visitors to experience them in some way?

In Transcranial Direct Current Stimulation, an electrical current is applied to the head and passed to the brain. Preliminary results suggest that TDCS could enhance memory and learning.

Alan gets a highly detailed scan of his brain. This image is the starting point for a search within his brain – as well as the brains of others – for the essential components of the Human Spark.

Alan Alda sets out to explore the difference between chimpanzees and ourselves, and quickly finds that the scientists studying chimps and other non-human primates are themselves separated into opposing worldviews.

Where and when did the Human Spark first ignite? In the caves of France, where 30,000-year-old paintings adorn the walls, as archeologists have long believed? Or at a much earlier time – and on another continent?

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