Shake It Off: Earth's Wobble May Have Ended Ice Age

"The last big ice age ended about 11,000 years ago, and not a moment too soon — it made a lot more of the world livable, at least for humans."

"But exactly what caused the big thaw isn't clear, and new research suggests that a wobble in the Earth kicked off a complicated process that changed the whole planet."

"Ice tells the history of the Earth's climate: Air bubbles in ice reveal what the atmosphere was like and what the temperature was. And scientists can read this ice, even if it's been buried for thousands of years."

"But when it comes to the last ice age, ice has a mixed message."