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Re: Pteromimus and pterosaur origins

Here's the problem with Atanassov's phylogeny. In his own words:

>>A total of sixteen terminal taxa are used in the analysis of Archosauromorpha,
including the tw o new reptiles Pteromimus and Procoelosaurus: Lepidosauromorpha
(outgroup); Rhynchosauria; Prolacertiformes; Proterosuchidae; Erythrosuchidae;
Proterochampsidae; Euparkeria. Parasuchia; Suchia; Omithosuchidae; Lagosuchus;
Dinosauria; Scleromochlus; and Pterosauria,<<

Note: only three generic taxa are represented here. All the rest are suprageneric. Which leaves open the question, which specimens/genera served as poster child for each of the suprageneric taxa? Considering the broad range of morphologies present in each clade, anything can happen.

Atanassov referenced Peters 2000, so why he chose not to include Longisquama, Sharovipteryx and the others can only be attributed to not being able to personally observe them.

There is also the question of cladistic _analysis_, which MacClade is great at. After thePAUP* tree(s) is(are) created it's time to evaluate it(them). MacClade is great at showing exceptions and mistakes in coding.

For instance, note that all of the sister and predecessor taxa of pterosaurs in Atanassov's phylogeny have a vestigial or absent pedal digit V. Pterosaurs don't. That's a red flag that should tell any reasonable person, evolution doesn't work that way and it's time to look for more parsimonious sister taxa. The same for manual digit IV. And there's a long list that follows. Anyone who claims that pterosaurs 'suddenly appeared' in the fossil record with no sister taxa demonstrating a gradual acquisition of characters has their blinders on. The data is freely available.

Those that test, discover.

David Peters