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Re: origin of bats/suspect trees? (combined answer)




On Jun 20, 2008, at 5:25 PM, David Marjanovic wrote:

The fossa has prehensile thumbs and carries stuff? I had no idea...

----- Original Message -----
From: "David Peters" <davidpeters@att.net>
Sent: Friday, June 20, 2008 4:11 PM

> The outgroup taxa used were Tupaia (tree shrew), Erinaceus (hedgehog), > Sus
> (pig), Felis (cat), Cynocephalus (dermopteran), run either as > unconstrained
> outgroups or constrained to a molecularly-based topology.


The problem here is twofold:

1. The outgroups are really way out. Closer outgroups have not been DNA tested.

None of the above is closer than the cat. Closer outgroups may be known, but no DNA can be known from them because they're Paleogene fossils...

Need to DNA test Ptilocercus and Nandinia alongside bats and dermoptera among other outgroups.

2. The authors state: "Because morphology based phylogenies of extant bats conflict with those based on gene sequences..." So...until DNA tests support morphology and vice versa (we can see the same problems within the Reptilia where even DNA testing does not agree with other DNA testing), DNA tests among varying genera will always be suspect. Within genera, the evidence is stronger as any CSI TV show will testify. And occasionally DNA gets lucky.

It is _painfully_ obvious that you don't have the slightest idea what you're talking about. You have even stooped to the genericometer fallacy! Argh.

Insults noted. Name two reptile DNA tests that agree with one another and reflect morphology.

----- Original Message ----- From: "David Peters" <davidpeters@att.net> Sent: Friday, June 20, 2008 8:05 PM

If the taxon lists are the same using morphology, the tree results will be the same, if you employ at least 150 characters. That’s the bottom line. That’s always been the bottom line.

For how many taxa? 20?

Doesn’t matter which characters. Delete cranials. Delete post- cranials. Delete axials. Delete every other character, or every tenth. If you test like this, you’ll see what I mean.

Either data matrices of tetrapod phylogeny are utterly abnormal (delete postcranials and get phylogenetic grass!), or what you say is utterly unrealistic.

I like that euphemism. "phylogenetic grass" . Sure, David, trees get damaged the more you take away. You guys are always so polarized. Take away less, less damage.

Getting back to bats: At least we should be looking for non-volant mammals with SOME bat characters, like broad flat ribs, reduced distal ulna, pedal proportions, wrist fusions, tooth counts, tooth shapes, etc. Funny thing is, there are such creatures, and they are arboreal, they’re just not cats, pigs and hedgehogs.

This is not at all surprising.

A reduced distal ulna comes with elongate forelimbs. Almost inevitably.

not birds, not pterosaurs, not primates.

Pedal proportions -- climbing.

sloths are different than lemurs. Do we count bats among the climbers?

Wrist fusions -- all over the place. Isn't there individual variations in humans in whether the centrale fuses to the 3rd distal carpal or not?
Tooth counts -- diet and head size & shape.
Tooth shapes -- diet.

: ) Nice to see Drs. Martin and Feduccia again. It's all about the suite of characters, David. Evidence accumulates until there's more here than there.

And the whole list makes up less than 10 characters anyway.

This is coffee talk, cocktail chatter. You're not getting the main course. Just open your mind to possibilities unexplored until now.

----- Original Message ----- From: "David Peters" <davidpeters@att.net> Sent: Friday, June 20, 2008 8:17 PM

> If necessary, I can provide references tomorrow. (As I will for
> the claims on LINE insertion... if I don't forget again...)

Sorry. Didn't have time. Had bureaucracy work to do.

So Nandinia isn't the African Palm Civet?

"African", yes. "Palm", yes. "Civet", no -- not for over 10 years now. _Never_ be content with reading Google snippet previews. Actually click the links to the results and read them! And never trust websites that don't look scientific on the phylogeny of anything. Even large parts of Wikipedia are way out of date.

David, the literature is not all-inclusive, nor is it gospel. If it were, we could all go home right now. You don't want to do that, do you? I know there are a few "facts" _you_ want to refute and a few discoveries _you_ want to make in your career. So why step on someone else's toes when all they are doing is raising their hand with a question and a possible solution for a problem that __no one__ else has ventured a guess on?

You seem to have missed all of the recent research on carnivoran (crown-group) and carnivoromorph (total group) phylogeny. Several of those papers were in Nature and Systematic Biology, in other words, rather hard to miss.

No, I've just been more inclusive than the current literature. So the results are different.



----- Original Message ----- From: "David Peters" <davidpeters@att.net> Sent: Friday, June 20, 2008 8:43 PM

Granted, certain tetrapods only need hind feet to climb (woodpeckers, etc.), but mammals, especially Paleocene ones, would have a tough time doing the same. So the question is, if bats were climbing using all fours, why and how would the change to using only the thumbs and folding the other fingers under actually work? IMHO there has to be an intermediate stage because if something is working right (climbing hands) they don’t change without intervention.

I repeat: *Onychonycteris*. There we have the intermediate stage. If you still haven't read that paper, I'll send it...

I think the real fun and meaty problem lies in what happened between Protictis and Onychonycteris. I don't expect much of interest out of future post-crania from Protictis.

If you look at Ptilocercus and Nandinia, both are quadrupedal climbers, but both hold their prey with their hands. Both enjoy inverted locomotion. Nandinia likes to jump out of trees. Ptilocercus has a fairly naked tail. Not much, but it’s a start.

What next? Whales and mesonychians as sister-groups because of a couple of intercorrelated tooth characters? The "flying primate hypothesis" (flying foxes and only flying foxes as primates -- either two separate origins of flight within placentals, or secondary flightlessness among primates) was much better supported, and yet it is still not the most parsimonious hypothesis, by far.

Again, these are only part of the formula. Do you walk around angry and sarcastic all the time? Or only when you respond to new hypotheses?


David Peters
davidpeters@att.net