[VadeRetro]

For some reason, the quote that I snipped is not a great example of what hit me wrong. For all that, the author's thesis is indeed "shallow roots and no prototypes."

The paper I would guess was written NLT 1980. It's a quarter century old and just wrong.

We know what was going on 700-600 million years ago. There was a big adaptive radiation at the end of the Snowball Earth glaciation.

But we also know "deep roots and tiny prototypes."

[Alamo-Girl]

Thank you for your reply!

I found a more recent article by the same scientist (with others contributing). This one was written 1999: Fossils, molecules and embryos: new perspectives on the Cambrian

On first blush, I cannot see a major shift in the view concerning durable skeletons and the Cambrian explosion - or a reduction of the interest in explaining the rise of so many body plans in so short a time.