The preceding Ediacaran life forms (635 to 542 mya) were gone already? Eaten up by early Cambrians (542 to 513 mya)?
From New Scientist:
The disappearance of the Ediacarans from the fossil record has long troubled biologists. Leading theories are a catastrophic mass extinction, that Ediacarans got eaten or had their habitat destroyed by newly evolved animals, or no longer left fossils because of a change in ocean conditions.
But a careful search by Marc Laflamme of the University of Toronto in Mississauga and colleagues threw up no geochemical signatures of low-oxygen conditions or other turmoil to support the idea of an environmentally driven mass extinction. And given that soft-bodied Cambrian animals are fossilised within rocks like the famed Burgess Shale, it seems unlikely that the conditions simply didn’t allow any surviving Edicaranas to leave a fossil trace in the Cambrian period.
That suggests that by the time the Cambrian explosion of species reached full force, the Ediacarans were gone
According to this interesting thesis, the early Cambrians simply ate up the Ediacarans within a few million years:
But he adds that although many of those Ediacarans were so strange that their biology makes little sense to us today, there is evidence that some of them did evolve movement and ways of ingesting food like modern animals, so may have given rise to life forms that evolved later. More.
So there was little of the Ediacarans left after the Cambrians gobbled them up, and then exploded, in numbers and type, as Steve Meyer has argued:
See also: Darwin’s Doubt, which reminds me:
- Amazon Best Sellers Rank: #16,041 in Books (See Top 100 in Books)
Imagine, Meyer’s Darwin’s Doubt is doing better in paleontology than in creationism.
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