Joined: Mar. 2005
Fossils older than dinosaurs reveal pattern of early animal evolution on Earth
|The abundant diversity of characteristics within species likely helped fuel the proliferation and evolution of an odd-looking creature that emerged from an unprecedented explosion of life on Earth more than 500 million years ago.|
Of course, "explosion" isn't really the right terminology for something that took place over several millions of years.
|But during the Cambrian Period, more complex creatures with skeletons, eyes and limbs emerged with amazing suddenness.|
Methinks it was likely the equivalent of what we call an "arms race" - lots of factions developing various strategies to cope with each other. All at once because once a few started developing more advanced strategies, anybody that didn't cope quickly enough went extinct. Leastwise that's my take on it.