Human Beings

French researchers conclude we have reached the pinnacle of our physical ability.

• By Tom Jacobs

Overly-connected groups may stifle innovation, new experiments suggest.

• By Nathan Collins

Until recently, the reigning theory on who the first Homo sapiens in North America were pointed to the Clovis people, evidence of whose culture was discovered in the American Southwest. That theory has been powerfully challenged by, among others, Meadowcroft, an archaeological dig in western Pennsylvania that began in the 1970s.

• By Steve Moyer