Are Two Cambrian Explosions Better than One?
Something seems wrong with this picture: deep sea creatures living in the dark were preserved in ash from a land volcano.
Science Daily just picked up on a press release from Oxford University that came out two weeks ago: the discovery of exquisitely-preserved Ediacaran creatures. Both articles explained that the Ediacaran fauna appear to bear no relationship to the Cambrian animals that came (in Darwin years) millions of years later, even though “where exactly they fit in the tree of life is unclear.” The discoverers believe the animals are baby rangeomorphs, animals with frond-like structures that “lived deep beneath the ocean where there would have been no light.”
That’s where their explanation for the burial seems puzzling: “A volcanic eruption around 579 million years ago buried a ‘nursery’ of the earliest-known animals under a Pompeii-like deluge of ash, preserving them as fossils in rocks in Newfoundland, new research suggests.” Lest one think this was an undersea volcano, Professor Martin Brasier clarified it:
‘We think that, around 579 million years ago, an underwater ‘nursery’ of baby Ediacaran fronds was overwhelmed, Pompeii-style, by an ash fall from a volcanic eruption on a nearby island that smothered and preserved them for posterity.’
By all accounts, the inhabitants of Pompeii that were buried by the ash fall from Mt. Vesuvius did not live at the bottom of the sea. One would think the ash would float, get diluted or be swept around by currents, not fall to this spot at the sea floor where the animals were living at the time.
It’s also not clear how the professors were able to spin the story into a blessing for Darwin. “The discovery confirms a remarkable variety of rangeomorph fossil forms so early in their evolutionary history,” the article said. Professor Brasier added another difficulty to the fact that they appeared in a remarkable variety out of nowhere: their diversification came “in an ‘Ediacaran explosion’ that may have mirrored the profusion of new life forms we see in the Cambrian.”
When you look in a mirror, you usually see an image of yourself. How the Ediacaran fauna could have mirrored the Cambrian, when there was no relationship between the creatures, is strange, unless it is like you looking through a clear glass at a tree and you both explode at the same time. Apparently this is what the eminent Professor professes: the Ediacaran explosion was just as rapid, and produced as many pieces of debris, as you and the tree.
This story is more proof that anything goes in Evolutionary Fantasyland, as long as Darwin gets the gory glory. Maybe one should ask, instead, why scientists keep finding so many examples in the fossil record of abrupt appearance of complex life, rapid burial, and exquisite preservation. What’s “evolutionary history” got to do with it?