At least eight new kinds of Earth's earliest animals from the mysterious and controversial Cambrian Explosion have been discovered in a unexpected section of ancient rock 30 miles from the famous Burgess Shale of Canada. The discovery suggests such old, rare fossils are more common than previously thought.

Like the fossils of the original Burgess Shale, the new discoveries are remarkable because they preserve features of animals which had no hard parts — like gills and eyes — and remained intact for more than half a billion years.

That's a time when animals evolved from being very small, simple organisms into a wildly creative, explosive variety of sometimes bizarre creatures.

These were culled by natural selection over time, leaving the more familiar main animal groups we see today.

Among the more dramatic discoveries is a new kind of "anomalocaridid" — the monster shrimp-like top predator a half-billion years ago. Some of these sorts of beasts have been found up to two meters long in shale from Chengjiang, China.
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MSNBC