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Re: Large last gasp of pterosaurs




John Bois <jbois@umd5.umd.edu> wrote:

Hey, you know what--I'm guilty of the same circularity as the bolide
arguments for Q. extinction: birds must have had the edge because
pterosaurs are extinct.


Don't forget: most avian lineages also went kaput. Only the neornithines survived beyond the K/T boundary. There's no evidence for enantiornithines and the rest of the non-neornithine lineages in the Cenozoic. Further, the corpus of fossil evidence suggests that the Neornithes were by no means the dominant avian lineage in the later Cretaceous. On the contrary, the neornithines were Cretaceous 'oddballs'.

Throughout the Mesozoic, the fortunes of many lineages rose and fell. The way I see it, just because the apparent decline of certain lineages (e.g., ichthyosaurs, pterosaurs) preceded the K/T boundary, this does not disprove (or even undermine) the occurrence of a global catastrophe of extraterrestrial origin. It is obvious that many lineages hit a wall at the K/T - including the non-avian dinosaurs.


Tim

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