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Researchers: Sand dollars and sea biscuits emerged earlier than thought


They are using the “molecular clock” technique to determine that:

Their analyses suggest that the ancestors of modern echinoids likely emerged during the Early Permian, and rapidly diversified during the Triassic period in the aftermath of a mass extinction event, even though this evolutionary radiation does not seem to have been captured by the fossil record.

Additionally, the results suggest that sand dollars and sea biscuits likely emerged much earlier than thought, during the Cretaceous period about 40 to 50 million years before the first documented fossils of these creatures. The authors say this result is remarkable, as the tough skeleton of the sand dollars, their buried lifestyles, and their extremely distinct morphologies imply that their fossil record should faithfully reflect their true evolutionary history.

eLife, “Early evolution of sea urchins” at ScienceDaily (March 22, 2022)

One wonders if that technique is not too risky in the absence of a fossil record. But “earlier than thought” has been a good bet in principle. Not so good for the “long, slow process of evolution” stuff though.

The paper is open access.

You may also wish to read: Bryozoa add to Cambrian Explosion’s impact: 35 million years earlier than thought So they are complex and that much closer to the dawn of life. At ENST: In Nature News and Views, Andrej Ernst and Mark A. Wilson write, “Bryozoan fossils found at last in deposits from the Cambrian period.” They had been “conspicuously absent” till now.

"I was pointing out what I believe are inaccuracies in the video." And so, (since I can nothing about any discrepancies in the video), I take it that you have now taken the time to drop a note in the video comment section so he might have an opportunity to clear up any discrepancies that you find troubling? Again, overall, I think he did a fine job on the video.,,, And he has more videos coming in the series. So if you are going to offer him any advice, now would be the time for you to do it. https://evolutionnews.org/2022/03/lukas-ruegger-three-problems-with-punctuated-equilibrium/ bornagain77
I think the narrator in the video did a fairly good job of explaining the overarching picture of punctuated equilibrium
What did I say that was not correct?
aside from complaining to me about the video
I was not complaining to you. I was pointing out what I believe are inaccuracies in the video. jerry
Well Jerry, nuances to however Darwinists choose to spin their various fairy tales aside, I think the narrator in the video did a fairly good job of explaining the overarching picture of punctuated equilibrium and explaining why it, in general, still fails as a coherent theory for explaining the Cambrian explosion. Anyways, aside from complaining to me about the video, perhaps you can drop a note to him, in his video comment section, if you would like to correct him on some technical matter about punctuated equilibrium. Unlike Darwinists, (who are, IMHO, beyond being 'corrected'), he seems to be very much a sincere 'seeker of truth' and thus I am sure he will try his best to make corrections to his video if they are necessary. bornagain77
Can Punctuated Equilibrium Solve the Cambrian Explosion
The narrator in this video does not understand punctuated equilibrium. He does accurately quote Gould but Gould’s followers believe the changes (new variations) are extremely slow just as Darwin has predicted. It’s just that the changes/variations are not perceptible till the right combination appears and then a major change happens because of these previously hidden but real changes. So in reality punctuated equilibrium is true Darwinian evolution. The issue is that this could not have happened because DNA is not the source of body plans. Nor could the changes needed for new systems happen even if DNA was the place where Evolutionary processes happened because of time limitations on the process for new variations. Let’s be accurate on what is actually proposed and deal with that. It is no threat to ID. When he was here several years ago, Allen MacNeill pointed Jurgen Brosius and that he was given the honor or eulogizing Gould in the evolutionary literature. Brosius’s article doing so pointed to a completely different way that punctuated equilibrium worked. Just as improbable as what the narrator in video said. But different. Aside: Brosius’s idea of punctuated equilibrium is researchable. And in bits and pieces it has been and essentially disproves punctuated equilibrium. jerry
Semi-related: New video:
Can Punctuated Equilibrium Solve the Cambrian Explosion? (Basics of ID Biology, Episode 3) https://www.youtube.com/watch?v=LcKonTyn7CY
Echinoderms are a puzzle. They share the styles and functions of mollusks in many ways. Secondary radial symmetry, using suction cups as tools. But echinoderms never developed intelligence. polistra
as to molecular clock
Molecular Clocks and the Puzzle of RNA Virus Origins Although the ultimate origins of RNA viruses are uncertain, it seems reasonable to assume that these infectious agents have a long evolutionary history, appearing with, or perhaps before, the first cellular life-forms (38). While the RNA viruses we see today may not date back quite this far, the evidence that some DNA viruses have evolved with their vertebrate hosts over many millions of years (24) makes an equally ancient history for RNA viruses a natural expectation. Yet a very different picture of RNA virus origins is painted if their gene sequences are compared; by using the best estimates for rates of evolutionary change (nucleotide substitution) and assuming an approximate molecular clock (21, 33), it can be inferred that the families of RNA viruses circulating today could only have appeared very recently, probably not more than about 50,000 years ago. Hence, if evolutionary rates are accurate and relatively constant, present-day RNA viruses may have originated more recently than our own species. https://journals.asm.org/doi/10.1128/JVI.77.7.3893-3897.2003

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