How many fossils are "out of place"?

one way to test it is to take a group of fossils and check if they fit with their phylogeny. now, take a look at this figure:


(image from “Molecules consolidate the placental mammal tree”)

as you can see- about 50% of the cases in the phylogeny that base on the morphological data arent fit with the their position that base on the molecular data. now, take a look at this tetrapod evolution (image from wiki):

remember that this series is base on morphology since we dont have genetic data from these fossils. it means that about 50% of the fossils in this figure arent realy fit with their supposedly real phylogeny that base on the molecular data, and thus are “out of place” actually (so a primitive fossil can appeare after more modern fossil). and this is even when we ignore the “out of place tracks” in the bottom left. remember that this is a single group out of many, so we actually have hundreds of out of place fossils.

I can’t actually see this. For one thing, your measure of discordance is unclear. Putting little x’s on various species communicates very little. For another, whatever does this discordance have to do with out of place fossils?

No, it means nothing of the sort.

So far you have not shown a single out of place fossil. You haven’t even managed to define what you mean by “out of place”.

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The image seems to be from the following paper:

[https://www.sciencedirect.com/science/article/pii/S0169534704001429](Molecules consolidate the placental mammal tree)

I cannot find the number 50% anywhere in the paper but I have just skimmed through it. Can you explain how you arrived at this number? How significant are the differences?

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For one thing, the morphological tree has only Paenungulata, with the rest of Afrotheria distributed throughout the tree. Afrotheria is a major achievement of the molecular studies. Again, what this can possibly have to do with out of place fossils is unclear.

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Is this a new thread that @scd has started on his own? Or is this a split from another thread? There seems to be a lot of context missing. Maybe that all exists in @scd’s mind, and he has yet to communicate it to us.

I think it’s a follow-up to this thread where scd made the ridiculous claim that Scansoriopteryx was “out of place” in the fossil record even though we have no record of where it was found.

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But that isn’t what you’ve done.

What you’ve actually done is note that for 50% of mammal orders the molecular and morphological phylogenies clash, and assume without any justification that this means 50% of the organisms on a completely different morphological phylogeny would also clash with the molecular phylogeny:

In the absence of any attempt to show that the level of clashes in the mammal phylogenies is the norm, your argument has all the validity of claiming that 50% of Texan cowboys wear Stetsons, therefore 50% of Japanese pearl-divers also wear Stetsons.

You’ve then compounded that completely unjustified extrapolation with the even more unjustified idea that any creature whose molecular and morphological cladograms clash must be somehow “out-of-place” in the fossil record:

Apart from the obvious* problem that “primitive” fossils can appear after “more modern” fossils because the emergence of new species with more derived traits does not require the extinction of the ancestral species, your ‘argument’ leads to the conclusion that 50% of all extant mammal orders are “out-of-place” in the fossil record.

Sloths are alive and well and living in South America. They didn’t go extinct millions of years ago. They have not yet to evolve. They are not, as your ‘logic’ would have them, “out-of-place” in the fossil record.

*To anyone who understands evolution, anyway.

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This diagram usually helps:

image

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i will respond later.

It won’t in this case.

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ok. as roy pointed out- my main idea is that if the morphological tree doesnt fit with the molecular one- its out of place case. if in general about 50% of the fossils contradict their molecular phylogeny- then they are “out of place” since they dont follow their true evolutionery order. so if by the morphological tree species A is suppose to be closer to species B than to species C, and then the molecular tree shows that actually species B is closer to species C, they are “out of place”.

first: what make you think that its not the norm? second: according to this fig it seems to be the norm also at the phylum level:


(image form Chapter 32 Class Presentation)

even if it was not the norm its still true for mammals, and since mammals represent a major group its still give us many out of place fossils.

not if we have fossils of them. i never said that a species should be extinct after its more modern form evolved.

You still seem to be thinking about some scala naturae rather than a tree. What do you mean by “true evolutionary order”? What you have actually seen is that some parts of the tree are hard to resolve with morphology (especially using outdated, intuitive methods of analysis) and others are hard to resolve, period. Neither the mammal tree nor the tree of phyla that you reference have anything in particular to do with fossis. In short, you are confused on a wide scale.

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Then (as I said) your ‘argument’ leads to the conclusion that 50% of all extant mammal orders are “out-of-place” in the fossil record. Since dead mammals do not vanish and sometimes reappear in the middle of million-year-old strata, your argument leads to a false conclusion. Either your argument is wrong, or your definition of “out-of-place” has nothing to do with fossils.

Fossils tend not to have a molecular phylogeny to contradict.

This has absolutely nothing to do with fossils.

First, I don’t know whether or not it is the norm. You haven’t produced anything to suggest it is, so your argument has a gaping hole in it. Second, another example isn’t enough to show anything about the norm.

Even if your argument was valid, it still wouldn’t give us any “out-of-place” fossils, it would only give us correctly-placed fossils of “out-of-place” animals.

So the fossils we have of extant mammals aren’t out-of-place, the out-of-place fossils are the ones we don’t have?

That’s ridiculous. I don’t think you know what your argument is. But whatever it is you’re trying to say, it’s about extant species, not fossils. You still have not produced any fossils of creatures that are misplaced in the fossil record. Not one.

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i dont think that its so different from reality. are you suggesting that “primitive” fossils should not appeare before “modern fossils”?. we do need to see a correlation between the morphology and the phylogeny, so a fish for instance should appear in the fossil record before a mammal since its suppose to be more primitive.

im not sure that i got your point here. say that the order 123 represent the evolution of mammals. now say that we find the order 132 instead. do you agree that 2 is out of place since it appear too late?

No, though the idea of “primitive fossil” is problematic. There actually is a substantial literature on the match between phylogeny and stratigraphic sequence, and when it’s tested the match is good. Still, it’s better to talk about primitive characters than primitive fossils, as most fossils have a mix of primitive and derived characters. Nothing you have presented so far is relevant to this question, since the morphological trees you have shown contain neither time nor fossil data.

Here’s something recent that might introduce you to the literature.

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Link didn’t work for me

Don’t know what to say. I tried it just now and it worked fine.

I’m absolutely certain that you didn’t get my point here. I even predicted that you wouldn’t.*

You said earlier that “i never said that a species should be extinct after its more modern form evolved.” But that is a necessity if you want the ‘2’ in 132 to be out of place.

‘123’ does not represent the evolution of mammals, or of anything else. Nor does it represent expectations of the fossil record or mammalian evolution.

If you insist on using numbers to represent evolution, it might look something like this:

1-1-1-1-1-1-1-12-12-12-12-12-123-123-123-123-123-123-123-123-13-13-13-13-13-13-13-3-3-3-3-3-3-3.

The bold numbers represent the fossils found. They’re not out of place.

*see post #9

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The first problem you need to solve is how you would determine that a specific fossil is the earliest member of that clade in the fossil record.

Second, primitive features can be passed on, even to the modern age. There are still fish, for example. There are very young fish fossils.

Third, our fossil collections are a tiny fraction of the fossils that do exist.

How did you determine that there is not an older fossil for 2?

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can you extend a little more about that point? i was thinking about similar idea. if most fossils have mix of traits it seems to fit with the mix idea.