You wrote:

LOL! There are plenty of taxonomic changes I've already mentioned in this thread (some of which even involve Pantherophis) that I disagree with. That's blind acceptance of taxonomic changes?



My response:

Such as?



You wrote:

And you seem to be ditching the adaptive radiation hypothesis...



My response:

The MP tree does not support it.



You wrote:

I think Utiger et al. can tell us more about Elaphe sensu lato because they include a whole lot more species of it. Simple as that.



My repsonse:

They tell us, for example, that Elaphe is not polyphyletic as a group. But you seem to reject that information because there are 4 papers cited by Utiger et al., in which the authors speculated that Elaphe is polyphyletic. You even claimed that they outnumber Utiger four to one, in spite of the fact that you never read these 4 papers. I have read two of them and neither show any data to support polyphyletic Elaphe.



You wrote:

I suggested that Pantherophis is a derived clade within Lampropeltini. Rhinechis and Pantherophis really aren't that similar, though. In basic external morphology and habits, Rhinechis is more similar to Pituophis.



My response:

Pituophis is a descendant of the ancient paraphyletic species Elaphe obsoleta (or sister taxon if you prefer) according to immunological data. Elaphe scalaris is morphologically similar to Pituophis. Does that suggest Elaphe obsoleta and E. scalaris are only convergently similar?



You wrote:

If you care to back that up, feel free to point out any error that I've made in either regard.



My response:

The fact that you think E. obsoleta (your “Pantherophis”) is a derived taxon shows that you do not know how to read the trees. This sort of phylogenetic relationship requires Elaphe obsoleta to lose the ancestral Elaphe characters it shares with Old World Elaphe (e.g. hemipenial structure) and then re-evolve very similar ones from a more derived condition such as that in Pituophis. Although Pituophis may seem to be similar to E. scalaris, its hemipenis does not look like those of Old World Elaphe. See for yourself by grabbing a hold of Dowling and Fries (1987, Herpetologica 43:200-207). All of the hemipenes of Elaphe, whether Old World or New World, are strikingly similar and thus indicative of a close relationship, especially in view of other similarities they share. Pituophis, though sharing some of the characteristics of Elaphe hemipenis, is clearly more derived, and it shares these derived similarities with its close relative Arizona, which has been described as a faded gopher snake. Clearly E. obsoleta is basal to Pituophis and Old World Elaphe is basal to New World Elaphe. Otherwise it would require 2 reversals for every similarity E. obsoleta shares with Old World Elaphe, if these similarities are only convergent. No change is definitely more parsimonious than 2 reversals.



You wrote:

I've never thought, or claimed, that Ptyas would make Elaphe sensu lato polyphyletic. And I already have mentioned other species that appear to be more closely related to Elaphe sensu lato and would thus be more likely to be grouped with it.



My response:

Denial again. You claim that the weakened statistical support for Ptyas as outgroup in Utiger et al. may mean that Elaphe is polyphyletic. I suggest instead that there may be something wrong with Utiger et al.'s data. Regardless, you never named a single species of racer that is more closely related to Elaphe than the species of Elaphe are to each other, which would in fact render Elaphe polyphyletic.



You wrote:

And I said that polyphyletic taxa have been recognized, and gave examples. No problem there.



Hint: a taxon is polyphyletic (or not) whether we know it or not.



My response:

That is not the point. I claim that no systematist will knowingly recognize polyphyletic taxa. Therefore the fact that Elaphe has survived intact for decades is prima facie evidence that it is not polyphyletic. You disagree but can cite no example of known polyphyletic taxa that continue to be recognized.



You wrote:

What similarities would those be, exactly? And what do you know of the morphology of their common ancestor?



My response:

I was asking you since you mentioned them. I take it that you do not know what similarity is shared by Elaphe obsoleta and Elaphe quatorlineata but not found in their common ancestor. Therefore you do not know which characters are supposedly convergent between these two species of Elaphe. If no one knows of the existence of such convergent characters, then the similarities between them is more likely than not shared derived characters. Molecular data also support this conclusion. They all show that Elaphe is not polyphyletic.



You wrote:

If you're going to tell me what most systematicists think, yes, you're going to need to've asked (or have access to some other source that asked, etc) them.



My response:

Why would any systematist claim that Elaphe is polyphyletic if there are three recent mtDNA analyses that refute this hypothesis and there is zero evidence that supports it? Systematists are scientists, and scientists rely on evidence (at least they are supposed to). If systemtists do what they are supposed to do, then most of them would indeed conclude that Elaphe is not polyphyletic. I do not have to ask them.

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