The missing fossils argument; new fossils found (Introduction)

by David Turell , Friday, August 02, 2024, 15:55 (113 days ago) @ David Turell

Another discovery of an early form:

https://www.science.org/doi/10.1126/science.ado0059?utm_source=sfmc&utm_medium=emai...

"Modern molluscs vary widely in form and size—including everything from giant squids to itty bitty snails. This intense variation evolved rapidly during the Cambrian “explosion” some 500 million years ago. However, there’s a bias in the fossil record, as shelled species are much more likely to fossilize than soft ones like slugs.

"But recently, a team of researchers unearthed a breakthrough find: a new species of mollusc that slimed the Earth 514 million years ago. Shishania aculeata, as the authors of a paper in the most recent issue of Science dubbed the creature, suggests that the world’s earliest molluscs were flat slugs with spiny armor instead of shells.

"The exquisitely preserved treasure, discovered in the Yunnan Province of southern China, reveals that the slug built its spines—spiky cones made of chitin—from a sophisticated secretion system shared by annelids like earthworms. An internal system of canals less than a hundredth of a millimeter in diameter indicate the cones were secreted at their base by soft microvilli in a process reminiscent of 3D printing. Meanwhile, underneath the animal was a muscular foot—a trait characteristic of mollusks.

“'Trying to unravel what the common ancestor of animals as different as a squid and oyster looked like is a major challenge,” said co-author Luke Parry in a statement. “The new fossil is an extra piece of the puzzle as it shows us what molluscs looked like before they evolved a shell ,” he told The Guardian."

Comment: The site for the full paper is above. This is a summary:

https://mail.google.com/mail/u/0/#inbox/FMfcgzQVxtmfvDZtcdqzXtxLRzTrHpTn

As usual the Cambrian Gap is reinforced by this new early form. The recent new discoveries all consistently add to evidence the gap is real. A regular disappointment for staunch Darwinians.