Hi Wulf,



One might say, a bit of both. First, they were unable to satisfactorily resolve relationships among Australasian pythons, apart from the strong distinction of Aspidites. Then they decided to adopt a classification that did not (according to the weakly resolved phylogeny) imply much more knowledge than they actually had.



Various reasons might be suggested for the low-resolution result, including inadequate sampling of taxa and characters, inadequate outgroup (Loxocemus, or was it Xenopeltis? - just one species, anyway), and an analysis method (rarely ever used) that throws away any characters that aren't perfectly consistent with the rest. The low amount of character evidence retained, and 'bad' outgroup, could result in the low resolution; the outgroup (again) and number of missing taxa could also result in the root being misplaced.



Given this result, it was quite proper (ideologically) to keep as genera only those groups that were supported as monophyletic by the analysis; and, conveniently, Storr & Smith's highly-lumped classification had been published only a few years before (my impression was that Storr & Smith had already been filled in on Underwood & Stimson's unpublished results).



Kluge (1993) worked with many more specimens and characters, multiple outgroups, and used maximum parsimony, so it's not surprising that he found a lot more phylogenetic structure. Of course, that doesn't guarantee getting the true tree!



Recent and current work at the South Australian Museum and other places is generating a lot of mitochondrial and nuclear sequence data, microsatellite characters etc., so we should know soon whether Kluge (as I suspect) rooted his cladogram in the wrong place despite his methodological rigour. It would seem hard to explain that all Oligocene and Miocene python fossils are either Python or Morelia (Scanlon 2001), if they are the last clades to have originated (as in Kluge 1993).



Cheers, John



Ref:

Scanlon, J.D. 2001. Montypythonoides: the Miocene snake Morelia riversleighensis (Smith and Plane, 1985) and the question of the geographic origin of pythons. Memoirs of the Association of Australasian Palaeontologists 25: 1-35.
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John D. Scanlon

Riversleigh Fossil Centre

Outback at Isa

Mount Isa, Queensland, Australia

riversleigh@outbackatisa.com.au

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