Page 58 - The Restless Earth Fossils

Marking turning points in evolution 57

that is now often referred to as the Cambrian Explosion.
Virtually every major group of animals alive today has ancestors
dating back to this time, including the chordates, the group
from which vertebrates like humans developed. But the Burgess
Shale also holds the remains of weird beasts that did not make
the final cut—animals like Opabinia, with five eyes and a claw on
the end of a “nose hose”; and Hallucigenia, a creature that was so
strange, scientists did not figure out for a long time which end

When he did so, he found that his fossil represented the remains of
a relatively large predator (about two feet long) whose mouth was
the creature first called Peytoia and whose two feeding arms were the
fossils called Anomalocaris!
In science, the name that counts is the name given to the first
fossil discovered. Anomalocaris thus became the name of one of
the first predators in the fossil record—a segmented terror whose
shadow hung over the trilobites and other shellfish whose armor
and spines were sometimes inadequate defense when it got hungry.
Stephen Jay Gould reveals additional details in his 1989 book,
Wonderful Life.

The Anomalocaris canadensis is an extinct animal thought to be
related to modern arthropods.

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