A Beautiful, Wonderful Solution to the Cambrian Puzzle?


(Dr. Patrick Trischitta) #1

Here is an article in Evolution News from DI. It comments on a recent published scientific paper on the Cambrian. Since here at Peaceful Science we have real scientists and a good mix of people interest in science and theology, we have the skills and temperament to comment on what EN says. Peaceful Science can be place where thoughtful discussion and pushback can take place. So here goes:

https://evolutionnews.org/2018/09/a-beautiful-wonderful-solution-to-the-cambrian-puzzle/


(Robert Byers) #2

The DI criticism is well done. All the new folks did was say , they guess, diversity in bodyplans happened quickly , with intermediates going extinct/not fossilized, and they solved the cambrian explosion problem.
It is a problem to evolutionists and is useful by ID however YEC denies the geology/fossils presumptions behind it all.
It all comes down to a faith of when the creatures died/deposited . Its all geology and not biology.


(S. Joshua Swamidass) #3

How quickly do you think the Cambrian Explosion took place? Over how many years?


(T J Runyon) #4

I see the DI put an emphasis on the word suggest in the paper. I’ve seen them do that before. They misunderstand it as meaning tentstive or cautious I guess. Means something else in scientific papers.


(T J Runyon) #5

I also want to know who writes this stuff. Some of it is so sad and juvenile and just pretentious. Really makes the DI look bad when they aren’t all like that. A lot of respect for Ann. I’ve recently started a private correspondence with Axe and I like him. They need to distance themselves from some of these folks


(T J Runyon) #6

Did you even read the paper, Byers?


(Blogging Graduate Student) #7

The ENV article quotes the University of Bristol press release as saying:

This image is based on the presence and absence of anatomical features, like jointed legs and compound eyes, neurons and boney skulls. Considering all of these features, animals that are similar group together, far away from animals that are dissimilar. Most of this ‘design space’ is unoccupied, in part because of extinction of ancient ancestors that are unrepresented, in part because animals have only been around for half a billion years and that is not enough time to explore all possible designs, but most of the design space is unoccupied because those designs are impossible.

ENV’s response to this is:

Did you hear that right? Ancestors that are “unrepresented”? What are those? Apparently, they are potential bodyplans that were never actualized because of limited time for evolution to “explore” those parts of “design space.”

Apparently the author didn’t read the paper. The caption in the press release was describing a single figure that only included extant species as data. So yes, extinct forms were “unrepresented” in that particular figure.

Throughout the ENV article the author makes little jibes about the apparent absence of transitional forms that “fill in the gaps” in morphology:

The paper appears to say that the authors simply imagined animals in the spaces where no remains are known

The “unrepresented” forms, therefore, must have appeared, and then disappeared without a trace.

They imagine transitional forms that are “unrepresented” in design space, but went extinct, leaving the appearance of gaps.

When you see gaps between the bodyplans, just imagine some intermediate forms that were exploring “shape space,” but went extinct, leaving gaps.

If they had read the paper, they would have found quotes like this one (my emphasis):

Our analyses demonstrate that, even though many (but not all) modern clades occupy discrete regions of morphospace, the inclusion of Cambrian taxa indicates that phylogenetic intermediates of living clades occupy concomitantly intermediate regions of morphospace. Combined with our inferences of the course of metazoan phylogeny through morphospace, these results indicate that the morphological discreteness of modern clades is largely a consequence of the extinction of phylogenetic intermediates.

In other words, including Cambrian fossils in the analysis plugs the gaps in morphospace - the reason phyla appear so discrete from one another today is because the morphologies that connect them are extinct - but we have the fossils.

WRT to this quote from the paper, the ENV article says that they paper’s authors are simply “imagining” animal forms:

we coded a phylogenetically diverse and representative sample of Cambrian taxa, principally the earliest representatives of ordinal level clades. This entailed coding 70 fossil taxa for the existing character set and adding 111 mostly autapomorphic characters. Coding these fossil taxa was potentially problematic in that most of the characters (54.1%) are not preserved, and therefore unknown.

However, if we read the paper (notice a trend?), we find that the authors were careful to highlight this point. The quote ENV uses is basically saying that the Cambrian fossils were incompletely preserved, missing half (54.1%) of their phylogenetically informative characters, relative to the extant taxa. They outline 2 ways around this missing data. First, they subsample their entire dataset using just the characters found in the Cambrian fossils, and get the same basic trend, with a few exceptions. These results still indicate that the Cambrian forms “fill in the gaps”, but the authors are interested in more than that, so they’re not satisfied with just this. The authors use another technique to infer the missing character states based on their phylogenetic position. This is the part where IDers and creationists shout “Huzzah! Look, they’re assuming evolution!” However, the authors explain (my emphasis):

There are obviously assumptions inherent in inferring missing data, including missing secondary reversals in soft tissues, the potential of differential evolutionary rates between preservable and nonpreservable characters, or limiting the coded fossil autapomorphies to preservable characteristics. However, given the rarity of reversals of superphylum-level nonfossilizable characters in extant taxa and the observation that autapomorphies contribute little to the construction of the morphospace (SI Appendix, Fig. S3), these assumptions are likely to have a minor impact on the projection of fossil taxa into the morphospace defined by the living species. The approach of inferring missing data likely strengthens the phylogenetic signal in the morphospace. However, a comparison with the taphonomically culled dataset (Fig. 2E) indicates a similar and robust placement of the fossil taxa within morphospace.

The ENV article is nothing but the usual predictable rhetoric, and does nothing to dampen the significance of this new paper.


(Robert Byers) #8

In YEC it was just a instant sediment load, from water movement, on top and then other loads, that day or weeks to come, that turned it all to stone.
so YEC would see a glorious diversity everywhere that would make the modern Amazon look like poverty street.
ID accepts the geological foundations that evolutionists do.
However it means that without the geology there is no biology conclusions or speculations.
Thus its not a biology science.but something else. A pet peeve of mine.
i’m saying its not a legit scientific investigation into biological origins EVEN though they draw conclusions about biological origins and say its scientific! maybe its me! Naw


#9

The problem you need to solve is why we don’t see any mammals, bony fish, reptiles, sharks, amphibians, trees, grasses, and a whole host of other species groups in the Cambrian. The only fish we see are very simple and don’t even have bones:

image

Where are all the bony fish with jaws and fins?


(Robert Byers) #10

In the diversity it would just be a special area. One doesn’t find your list anywhere in a special area on earth today.
I don’t agree there are mammals, reptiles etc divisions. So its easily also, in other cases, misidentification.
For example I’m quite confident that what are called dinosaurs/rapters are in fact just giant ground birds. This error was made long ago and only today they now note how birdlike they are and say moder=n BIRDS are dinosaurs too.!! Yet its the opposite way. Those were not dinosaurs but just big ground birds. Big ground birds have a history in the fossil record otherwise.
They group creatures based on traits but the traits are not proven they are related.
snakes, platypus, birds all lay eggs but its just a good idea with limited options in the biological blueprint God created.
By the way fish are never simple. They are still very complex. Some human said they were simple relative to others. They never said that. Another error.


#11

Which Cambrian fossils are actually whales but are being misidentified?

There are no land vertebrates of any kind in Cambrian deposits. How do you explain this?

There are no fish with bones and jaws in the Cambrian. How do you explain this?


(Dr. Patrick Trischitta) #12

ENV isn’t quite finished on the Cambrian. See more comments:

https://evolutionnews.org/2018/09/ignoring-other-research-new-study-explains-away-the-origin-of-new-body-plans/


(John Harshman) #13

I tried to read that article, but the contempt for science and for scientists that dripped from every sentence quickly became too annoying for me to continue.


(S. Joshua Swamidass) #14

It is hard to understand when one’s main point depends on not understanding. I wouldn’t give it to much sweat.


(Robert Byers) #15

If this is just a moment in time that fossilzed a local area then it would only include those creatures at that moment living there… It is a moment in time and this is just a segregated area just like now on earth.
Your cambrian division is a misidentification. Its just a collect from nicjes , everywhere, that are on the outsjirts of other areas.
The cambrian, might, just be the swamps and its sudden collection/ deposition is just the lower parts of a general sediment movement by the water. its only showing areas and not timperiods.
They don’t know there is a cambrian period but only find a depositional unit that is generally laid about and has different deposition units above it.
it doesn’t show time/creatures but sections of earth.


#16

You said that these areas were extremely diverse, so why can’t we find a diverse set of organisms? We can’t find a single mammal of any kind in any Cambrian deposit anywhere in the world. We also can’t find a single bony fish in any Cambrian deposit. Your explanation just doesn’t add up.


(Robert Byers) #17

They are diverse, greatly, in those types for those enviroments. On all assemblages that were fossilized there is no expectation of a diversity including fish and mice. The deposition event only took in those areas it was involved in.


#18

No, they aren’t. There are no bony fish anywhere in any Cambrian deposit. There are no mammals in any Cambrian deposit. No bony fish, no grasses, no trees, no flowering plants, no reptiles, no amphibians, no birds . . . I could go on and on.


(Dr. Patrick Trischitta) #19

What about Rabbits in the Cambrian? :rofl:


(Jonathan) #20

@T_aquaticus, @Patrick
But there are (of course) the exceptions, right :wink: ? For instance, the pollen microfossils that were discovered in the Roraima formation in South America (which, if I am not mistaken, is supposed to be of Precambrian age, which is probably just as good as the Cambrian for the purposes of this discussion)!