Weird Antarctic ice may explain how life endured on frozen Earth

Millions of years ago, Earth was a frozen "snowball"

Millions of years ago, Earth was a frozen “snowball”

Jason Edwards / Getty

How did complex life survive when the Earth turned into a giant snowball hundreds of million years ago? A bizarre region of “dirty” Antarctic ice, discovered a century ago by British explorer Captain Scott’s team, might hold clues.

There is evidence that Earth experienced at least two astonishingly severe ice ages between 717 and 636 million years ago. Some researchers say conditions were so extreme that ice reached the equator – so our planet effectively became a giant snowball.

If it happened, Snowball …