Sander van der Leeuw
April 28, 2010
For most of the 2.5 million years that humans and their predecessors have been around, the Earth has been a volatile place. Subtle shifts in the planet’s orbit have triggered large temperature swings; glaciers have marched across North America and Europe and then retreated. But, about 10,000 years ago, something unusual happened: The Earth’s climate settled into a relatively stable state, global temperatures started hovering within a narrow band, and sea levels stopped rising and falling so drastically.