@farmerman,
farmerman wrote:This adds more fuel to the fire that the "Cambrian Explosion" had its roots further back than previous thought.
I thought that had always been pretty obvious. After all, the creatures of the Cambrian didn't just poof in out of nowhere. The illusion of an "explosion" is just the result of empty spots in the record due to limited exposure of geologic structures from certain times. Going back beyond this, the empty spots are due to an even more intransigent problem; the organisms were soft, and just don't fossilize as easily (or in as many conditions). The only reason we recognize stromatolites as fauna is because their secretions collect particulates which form structures. Otherwise they would be invisible to us, as many of the things that existed back then probably are. We picture the precambrian seas as full of all the things that we find fossils of, but the reality is that those are probably only a tiny fraction of what was really there.
The same applies to almost every epoch of history. As humans we can't help but picture the world full of only thing things we see. As such, Tyranosaurs, Stegasaurs, Pteradons, Ambylocetus, Anomalocaris and Pikaia were probably the "squirrels" of their age, the most common of the fauna. Likewise, any soft-bodies creatures which didn't fossilize are invisible to us, even though the seas of the Ediacarian were probably teeming with them.