Crocodylomorph study omits a long list of basal taxa

Wilberg, Turner and Brochu 2019
bring us the “evolutionary structure and timing of major habitat shifts in Crocodylomorpha.” 

Unfortunately
Wilberg, Turner and Brochu 2019 omitted a long list of basal bipedal crocodylomorpha (Figs. 1, 2), and considered an ingroup, Gracilisuchus, an outgroup. They also considered the unrelated giant rauisuchid, Postosuchus, an outgroup taxon.

Missing from the Wilberg, Turner and Brochu study
are a number of basal Crocodylomorph taxa and their outgroups, as determined by a wide gamut analysis of reptiles (= the large reptile tree = LRT; subset Fig. 1).

Ingroup Crocodylomorpha in the LRT
omitted by Wilberg, Turner and Brochu include: YPM VP 057 103, Pseudhesperosuchus, Carnufex, Trialestes, Lewisuchus, MCZ 4116, Saltopus, Scleromochlus, SMNS 12591, Terrestrisuchus, Tarjadia, Parringtonia, Litargosuchus, Erpetosuchus, SMNS 12352, Pedeticosaurus, Yonghesuchus, Dromicosuchus, Saltoposuchus and Dyoplax.

Outgroups to the clade Crocodylomorpha in the LRT omitted by Wilberg, Turner and Brochu include: Herrerasaurus + Staurikosaurus (at the base of the Dinosauria), PVL 4597 (at the base of the Archosauria = Crocodylomorpha + Dinosauria), Turfanosuchus (proximal outgroup to Archosauria), Decuriasuchus + Pagosvenator (second proximal outgroup to Archosauria).

Figure 1. Subset of the LRT focusing on the Crocodylomorpha, dorsal scutes, elongate proximal carpals, bipedality and clades.

Figure 1. Subset of the LRT focusing on the Crocodylomorpha, dorsal scutes, elongate proximal carpals, bipedality and clades.

Simply adding taxa
solves all these problems and documents a more gradual accumulation of derived traits and major habitat shifts.

Figure 1. Ten basal bipedal crocodylomorphs descending from a sister to Decuriasuchus.

Figure 2. Ten basal bipedal crocodylomorphs descending from a sister to Decuriasuchus.

References
Wilberg EW, Turner AH and Brochu CA 2019. Evolutionary structure and timing of major habitat shifts in Crocodylomorpha. Nature.com/scientificreports DOI:10.1038/s41598-018-36795-1

wiki/Crocodylomorpha

6 thoughts on “Crocodylomorph study omits a long list of basal taxa

    • Thanks for writing, Chris. Why did you omit so many basal in-group taxa in your study? Why did you employ the unrelated Postosuchus as your out-group? Why did you consider Gracilisuchus an outgroup when the LRT nests it as an ungroup? And why did you omit more closely related outgroups? The LRT pointed the way.

      • OK – I’m still not seeing a problem with respect to the overall conclusions of the paper.

        Once the LRT has been published in the peer-reviewed literature, we will consider it. May I ask when we can expect this to happen?

      • Several attempts, all rejected for 1) not seeing specimens firsthand, 2) not having enough characters, 3) extending to clades the referee had no expertise, 4) for no reason. So, it’s too big, not big enough, breaks tradition, and workers don’t want it published.

        When I have seen specimens and reported on them, even reporting on mistakes I had made earlier, workers did not want those conclusions to enter the literature.

        When I have had cladograms published, no one cited them, except to note they were heterodox, then ignored or dismissed them without testing. Whenever I had work published it was because only one referee said it was okay. The other was generally vicious in their comments. Once both referees rejected a work, but the editor published it anyway, embarrassed by their ruthless responses.

        As I view it, peer-review permits invalid, truncated and biased cladograms to be published, so peer-review is not what one would hope it could be. The LRT is presently the best solution for getting suggested pertinent taxa out there. You don’t have to use the characters, but the taxa should be considered in your own way.

        Thanks for asking, Chris.

  1. Also – for specific answers to your questions about Postosuchus and Gracilisuchus, I would point you to Eric Wilberg’s previous papers, one in JVP and the other in Systematic Biology.

    • Just found this in the unapproved comments section. Sorry for the delay. I checked Wilberg’s paper list in ResearchGate and found no titles that appear to fit your comment. Can you provide article titles so I can zero in on those papers? Thank you and apologies.

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