Sometimes we miss the big picture.
Here then, for your approval and disapproval are comparisons between closest kin found by the Nesbitt (2011) tree versus those found by the large reptile tree. Over the last few days we looked at problems with Mesosuchus, Vancleavea, Euparkeria and Parasuchus.
You knew this was coming!
Today we’ll look at Nesbitt’s odd nesting of pterosaurs in this clade.
Figure 1. The nesting of pterosaurs in Nesbitt (2011), the current “Gold Standard” for the nesting of archosaurs and their relatives. Unfortunately, pterosaurs don’t belong here, as can quickly be seen by side-by-side comparisons.
- Pterosaur Kin According to Nesbitt (2011)
Here (Fig. 2) are the selected Nesbitt (2011) sisters for visual comparison.
Figure 2. The phytosaur, Parasuchus, surrounded by putative sisters according to Nesbitt 2011. Euparkeria was more primitive. Eudimorphodon and Ornithosuchus were more derived. Does anyone else see a problem here?? Why was this result NOT widely criticized?
Pterosaur kin according to the Large Reptile Tree
The large reptile tree found Huehuecuetzpalli, Cosesaurus and Longisquama (Fig. 3) to be successively closer to pterosaurs because they share an increasing number of pterosaurian traits.
Figure x. The lineage of pterosaurs recovered from the large reptile tree. Huehuecuetzpalli. Cosesaurus. Longisquama. MPUM 6009. Here the gradual accumulation of pterosaurian traits is documented.
One look at these results brings immediate understanding that there’s something wrong in the Nesbitt (2011) matrix that produces such strange bedfellows and no indication of a gradual accumulation of character traits. Pterosaurs and their origins have been covered perhaps more than any other subject here and at reptileevolution.com, for those who want more details.
As always, I encourage readers to see specimens, make observations and come to your own conclusions. Test. Test. And test again.
Evidence and support in the form of nexus, pdf and jpeg files will be sent to all who request additional data.
References
Nesbitt SJ 2011. The early evolution of archosaurs: relationships and the origin of major clades. Bulletin of the American Museum of Natural History 352: 292 pp.
The Pterosaur Heresies 