A couple of highlights:
So they found about 100 taxa, and half of those are new to science. Creationists like to say that we have found all of the fossil species we will ever find. Guess they were wrong.
Cool. Pity it’s paywalled.
These fossil kick another battleship sized hole in Stephen Meyer’s Darwin’s Doubt claims. I wonder if Trollhoffer at the DI will be writing about them anytime soon.
I hope Greg takes a look at these new lagerstätte fossils, the ones Kurt Wise assured him couldn’t form.
Meyer claimed all the fossils found in the Burgess shale were specially created with no ancestral forms. These new finds are 10 MY earlier and show evidence of being the ancestors of the Burgess biota, especially the primitive jellyfish.
Meyer’s entire idiotic claim is based on the lack of fossil evidence for early Cambrian ancestral species. Lots of people told him lack of evidence isn’t evidence of lack. Now we have some of his missing evidence.
Don’t remind me. I retired in Jan. after a productive 40 year career. Unfortunately I lost access to my lab’s subscriptions to Science, Nature, and many other top line science journals. I’m trying to decide if it’s worth the $200-300 per year to get a personal subscription.
Have you forgotten the Chengjiang, which may be a bit older than this new one? Nor do I see so far (given that I have no access to the paper) anything like evidence of ancestry. Then again, it’s really impossible to identify ancestors in the fossil record.
Anyway, the evidence you are looking for is in the small, shelly fauna and accompanying ichnofossils, not in any of the Cambrian Stage 2 Lagerstätten.
He has a silly sponge embryo argument in response to that. Meyer has always been iffy of stem-crown group thinking. He rules out all the stem-groups because in some groups the crown groups appear before the stem (implying a ghost lineage) and for some reason Meyer thinks ghost lineages can’t exist and aren’t a real thing. So he is able to do some hand waving and dismiss discoveries like this
Edit: like @John_Harshman I haven’t read the paper yet so I’m not gonna say a lot but when I see words like primitive I think stem-group which is what you expect of common ancestry.
Did you miss this reference in the NatGeo overview to a sister paper published today also?
The origin of ctenophores (comb jellies) is obscured by their controversial phylogenetic position, with recent phylogenomic analyses resolving either sponges or ctenophores as the sister group of all other animals. Fossil taxa can provide morphological evidence that may elucidate the origins of derived characters and shared ancestries among divergent taxa, providing a means to “break” long branches in phylogenetic trees. Here we describe new fossil material from the early Cambrian Chengjiang Biota, Yunnan Province, China, including the putative cnidarian Xianguangia , the new taxon Daihua sanqiong gen et sp. nov., and Dinomischus venustus , informally referred to as “dinomischids” here. “Dinomischids” possess a basal calyx encircled by 18 tentacles that surround the mouth. The tentacles carry pinnules, each with a row of stiff filamentous structures interpreted as very large compound cilia of a size otherwise only known in ctenophores. Together with the Cambrian tulip animal Siphusauctum and the armored Cambrian scleroctenophores, they exhibit anatomies that trace ctenophores to a sessile, polypoid stem lineage. This body plan resembles the polypoid, tentaculate morphology of cnidarians, including a blind gastric cavity partitioned by mesenteries. We propose that comb rows are derived from tentacles with paired sets of pinnules that each bear a row of compound cilia. The scleroctenophores exhibit paired comb rows, also observed in Siphusauctum , in addition to an organic skeleton, shared as well by Dinomischus , Daihua , and Xianguangia . We formulate a hypothesis in which ctenophores evolved from sessile, polypoid suspension feeders, sharing similarities with cnidarians that suggest either a close relationship between these two phyla, a striking pattern of early convergent evolution, or an ancestral condition for either metazoans or eumetazoans
ID folks like to point out that a lot of the SSF are problematica (which is true) but fail to mention that many have been identified as armor of larger animals
Despite how the DI butchers and/or ignore the evidence this find is damn cool! I’ll find a way to wrangle a copy somehow.
No. But you should note that a) stem group ≠ ancestor, and b) people who work on ctenophores have ridiculed the suggestion.
They would be collateral though, no?
A stem group is a stem group. I consider “collateral ancestor” a meaningless term. Now of course stem taxa can tell you a lot about relationships if they display a lot of primitive or intermediate characters.
Emailing the senior author and asking for a PDF usually works.
Thank you for posting this; very interesting discovery. Having just read their article, this seems to me to be the most important take-aways:
The Qingjiang fossil locality is of exceptionally high quality, with undisturbed and detailed specimens, even of fragile organisms like cnidarians. This supports previous work indicating that older deposits are no less detailed due to being old, and that Cambrian deposits are in fact of better than average quality compared to the totality of the fossil record.
The locality has a suprisingly high level of diversity, with many previously unknown taxa, especially cnidarians.
The assemblage varies from that found at the Chengjiang locality, with many taxa from Qingjiang not found at Chengjiang and vice versa. This variety is probably due to the two localities representing different ecological zones, not differences in preservation. In other words, we are probably underestimating the diversity of the Cambrian biota.
The full significance of the Qingjiang locality is yet to be seen, as researches study the specimens in detail, trying to fit them into existing phylogenies or revising those, when required.
What a time to be alive.
A methodological question: If Stephen Meyer accepts by inference that Cambrian animals from the Burgess shale are at least representative as ancestors of extant life, how would he then argue that animals from even older strata (Ediacaran) are not to be inferred as representative ancestors of Cambrian life? Can’t wait to hear about what cherrypicker contortions he’ll invoke for this one.
He can’t have his cake and eat it too.
Is it the consensus view that the organisms from the Ediacaran biota are ancestors of modern animals?