The human race almost went extinct:
With 6.8 billion people alive today, it's hard to fathom that humans were ever imperiled. But 1.2 million years ago, only 18,500 early humans were breeding on the planet--evidence that there was a real risk of extinction for our early ancestors, according to a new study.
This article available online at:
http://www.theatlantic.com/daily-dish/archive/2010/01/evolutionary-bottlenecks/191309/
