WW wrote:

"The most recent papers on the subject are:

Slowinski, J. B. and R. Lawson. 2002. Snake phylogeny: evidence from nuclear and mitochondrial genes. Mol. Phylogenet. Evol. 24:194-202.

Vidal, N. and S. B. Hedges. 2002. Higher-level relationships of caenophidian snakes inferred from four nuclear and mitochondrial genes. C. R. Biologies 325:987–995.

Vidal, N. & S.B. Hedges. 2002. Higher-level relationships of snakes inferred from four nuclear and mitochondrial genes. C.R. Biologies 325: 977-985.

Kelly, C. M. R., N. P. Barker and M. H. Villet. 2003. Phylogenetics of advanced snakes (Caenophidia) based on four mitochondrial genes. Syst. Biol., 52:439-459.

And before out trolling but ignorant friend starts to whine about ignoring older evidence, let me point out several of these papers incorporate the exact sequencees used by Heise et al., but come to different conclusions by virtue of different methods of analysis and the inclusion of more taxa (the position of Atractaspis is one of them).

Cheers,

Wolfgang"

Me:
WW seemed to have me in his crosshairs when he wrote his message. He seemed to realize that he in fact prefers newer data or newer analyses of old data and he attempted to obviate my criticism by his comments. Let me point out that it is often difficult to decide which one of two or more different contradictory hypotheses of relationships, if any, represents objective truth. That is because, once again, as George Gaylord Simpson pointed out, phylogenetic history cannot be directly observed and must be inferred. If a different method of analysis produces different results, it is probably because one or more of the following is true:

1) The characters are not any good.

2) The methods of analysis are not any good.

3) The authors picked the wrong tree from among many produced by the computer.

And as J.D. Lazell (1994 Herpetol. Rev.) said, "I question that making consensus cladograms out of X-1 certainly wrong trees and maybe one right one has much to do with science or reality." Therefore it is a bad idea to classify animals strictly according to the topography of even consensus cladograms, which have little to do with science or reality, as WW and his cladistic colleagues insist we must do. Classifications that are subject to the constant changes in the preferred hypotheses of branching order are useless for scientists, since the only useful classification is a reasonably stable one.

I have seen the trees in Vidal and Kelly and I am not impressed. They seem to require a lot of additional work to make them more believable. As to Slowinski and Lawson, their trees from the nuclear and cytochrome b genes also conflict strongly with one another and with Kluge's tree, which is derived from morphological characters. Specifically, in one tree Charina bottae and Lichanura trivirgata cluster with Boa constrictor, whereas in another C. bottae and L. trivirgata cluster with Exiliboa and Ungaliophis. Since Calabaria is not included in Slowinski and Lawson's analysis, there is no clue as to where Calabaria may lie in those trees. Slowinski and Lawson's two different trees can be used to produce vastly different classifications. Another author with a different set of trees and a newer publication date (the presumed tie-breaker) presumably can result in yet another completely different classification. For those people who like to play around with names, that is probably acceptable or even "cool." For scientists who need a stable taxonomy for information retrieval and effective communication, the constant stream of new phylogenies based on different characters or even different methods of analyzing the same old characters can be most annoying if classifications must be based strictly on branching order. An unstable taxonomy is nothing to cheer about for most scientists.

All of these papers that WW cited give us good reason to ignore Kluge's lumping of Charina bottae, Lichanura trivirgata and Calabaria reinhardtii into the same genus, if the morphological disparity among these taxa have not provided good enough reason before. Kluge's tree is contradicted by Slowinski and Lawson's trees and any classification of the dwarf boas on the basis of a strict application of Hennigian taxonomy is premature.

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