You wrote:

But, IIRC, all the Old World `Elaphe' Lopez and Maxson use are in Elaphe sensu stricto. Most of the problematic members of Elaphe sensu lato are not in Elaphe sensu stricto, so this isn't a good test.



My response:

Not so. Elaphe scalaris, which is one of the species analyzed by Lopez and Maxson is considered a member of the monotypic "Rhinechis" by Utiger et al.



You wrote:

Adaptive radiation, of itself, doesn't have any consequences for

resolution of a genetically-based phylogeny.



My response:

If several species evolve from a single species so quickly that there is no time for the mtDNA to evolve into more than 1 lineage, then all of the species will have identical ancestral mtDNA markers, with subsequent autapomorphic changes appearing in each descendant species but no common markers to link any species pair more closely to each other than to other species. The result is an unresolved polytomy involving multiple species, such as the kind seen in Rodriguez-Robles et al.'s analysis of the Lampropeltini. Adaptive radiation can result in polytomies. This is something that competent systematists know.



I wrote:

'Your slim hope that Utiger et al.'s data somehow suggest that Elaphe is polyphyletic has been dashed by Tong et al.'s bootstrap value of 98 for the Ptyas-Elaphe split.'



You wrote:

This has already been addressed.



My response:

That is not possible. This is the first time I brought up Tong et al's bootstrap value for this node.



You wrote:

The relationship of Old World taxa to New World taxa to each other is not the issue. The relationships to each other of all members of Elaphe sensu lato, whether they happen to be New or

Old World, is the issue. As a result, your argument above, which is predicated on the sole importance of New vs. Old World taxa, doesn't apply.



My response:

Tong et al. show that all of the Old World species of Elaphe, including the most basal member, Elaphe mandarina, form a monophyletic group with Ptyas as the outgroup. Lopez and Maxson show that all species of New World Elaphe (along with their descendants in the Lampropeltini) form a monophyletic group with the Old World species they study basal to the New World clade. Ptyas is the outgroup. Utiger et al. find that New World Elaphe plus the Lampropeltini form a clade with the Old World species of Elaphe basal to the New World clade and Ptyas as the outgroup. The similarities in their findings suggest that Old World Elaphe is paraphyletic with respect to New World Elaphe and New World Elaphe is paraphyeltic with respect to the Lampropeltini. All of these species (Old World Elaphe plus New World Elaphe plus the Lampropeltini) form a clade with Ptyas as an outgroup. Conversely, there isn't any study that demonstrate polyphyly in Elaphe. Hence Elaphe is not polyphyletic.



I wrote:

`Utiger et al. cite 4 papers. One of these (Dowling et al.), as I point out, cannot possibly make that conclusion since it does not include a single species of Old World Elaphe in it.'



You wrote:

Ok. But what if they thought that New World members of Elaphe sensu lato formed a polyphyletic group?



My response:

That is not possible. Their data shows that New World members of Elaphe are all part of a monophyletic group they call "Elaphini." As I said, they have a hunch that Old World Elaphe and New World Elaphe may form a polyphyletic group, but they have no data to show one way or another. Utiger et al., nevertheless, cites this paper for evidence that some authors have concluded that Elaphe is polyphyletic. Dowling et al. are merely speculating about this possibility since their data cannot answer that question one way or the other.



I wrote:

`A second paper (Dessauer et al. 1987) is claimed by Tong et al. to have made an assumption for Elaphe polyphyly.'



You wrote:

So why should we take their word for it?



My response:

If any author had convincingly demonstrated that Elaphe is polyphyletic, it would not have survived the past decade and a half intact. It is quite obvious that Dessauer et al. are speculating based on that fact alone.



You wrote:

So you claim to have refuted two papers by Dessauer that you haven't even read?



My response:

I might not have read it, but Tong et al. did. I have since read it, and there is nothing in there that shows Elaphe is polyphyletic. Dessauer et al. find that Elaphe quatorlineata is basal to New World Elaphe and the Lampropeltine species. That is consistent with the results from the newer papers that refute Elaphe polyphyly.



You wrote:

You're also forgetting another paper I mentioned. I don't recall the citation offhand, but it's in the thread somewhere.



My response:

I do not remember any such paper. Please refresh my memory.



You wrote:

Now this is an interesting argument. You appear to be saying that, since Dowling, Minton, and Dessauer would have dismantled Elaphe sensu lato if they believed it to be polyphyletic, Elaphe

must be either mono- or paraphyletic. However, we already know that these authors have stated that they believe Elaphe sensu lato is polyphyletic, and we already know that they didn't dismantle it. So the premise of your argument is clearly false...



My response:

They would have dismantled Elaphe if they had proof that it is polyphyletic. Absolutely! They have no proof that Elaphe is polyphyletic. That is why they do not dismantle it. Nothing wrong with my argument, especially since I have shown that Dowling et al. and Dessauer have no data to prove that Elaphe is polyphyletic. I still haven't read Minton but I am confident that he has no data to show that either.



You wrote:

Apart from that, a taxon's long-term recognition is very poor evidence of mono- or paraphyly.



My response:

Do you have any evidence that a polyphyletic taxon, any polyphyletic taxon, has continued to be recognized despite its polyphyletic status? Let me guess: Elaphe!



You wrote:

`Basal to' does not mean `ancestral to'.



My response:

True. But a lineage that is basal to another can indeed be ancestral to it.



You wrote:

If Dessauer's results are as you suggest, they mean that the Lampropeltinines and Elaphe quatuorlineata form sister taxa among the taxa studied by Dessauer, i.e., that they share a more recent common ancestor than either does with any taxa. It doesn't say anything about what that common ancestor was.



My response:

If New World Elaphe and E. quatorlineata share a recent common ancestor, then there are two possibilities. Their common ancestor is a species of Elaphe or they are only convergently similar, meaning that their common ancestor is not like Elaphe and that the New World species of Elaphe are only convergently similar to E. quatorlineata. The second alternative is certainly possible, but not as parsimonious. Most systematists would agree that New World Elaphe is descended from an Old World species of Elaphe. Most systematists would agree that Elaphe is not polyphyletic.

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