If you could dive down to the ocean floor nearly 540 million years ago just past the point where waves begin to break, you would find an explosion of life.
If you could dive down to the ocean floor nearly 540 million years ago just past the point where waves begin to break, you would find an explosion of life—scores of worm-like animals and other sea creatures tunneling complex holes and structures in the mud and sand—where before the environment had been mostly barren.
“We can see from the trace fossils—tracks, trails, borings, and burrows animals left behind—that this particular environment of the ocean floor, the offshore, served as a ‘crucible’ for life,” said USask paleobiologist Luis Buatois, lead author of the article. “Over the next millions of years, life expanded from this area outwards into deeper waters and inwards into shallower waters.”
The research is the culmination of more than 20 years of work from Buatois and the team which examined hundreds of rock formations in locations across every continent.
“Until now, these two events—the Cambrian Explosion and the Great Ordovician Biodiversification Event—have been understood mostly through the study of body fossils—the shells, carapaces and the bones of ancient sea creatures,” said Buatois. “Now we can confidently say that these events are also reflected in the trace fossil record which reveals the work of those soft-bodied creatures whose fleshy tissues rot very quickly and so are only very rarely preserved.”
Continue reading at University of Saskatchewan.
Image via Xiaoya Ma.