On Tue, Sep 29, 2020 at 6:33 AM Mike Taylor <sauropoda@gmail.com> wrote:
Here is Darren Naish's take, in a Twitter thread starting at https://twitter.com/TetZoo/status/1310866093582548994. (Darren is a long-time collaborator with Dave Martill.)> Here's what I think happened. The Daves DO think that pterosaurs were naked, even though the idea is wrong and was shot down in flames when presented at SVPCA 2019. They tried to get it through review and failed, the only part of their ms surviving being the bit contesting the interpretation of branched fibres - hence the published technical paper. But - as a way of getting the 'naked' idea out there and into consciousness - they used the press release to push the naked idea and had new art commissioned for it. I'm checking now; if I'm mistaken I'll apologise and delete these tweets.-- Mike.On Tue, 29 Sep 2020 at 05:24, Mickey Mortimer <mickey_mortimer111@msn.com> wrote:Is it just me, or did the paper not say at all what the press release reported? Unwin and Martill's paper never dismisses the idea of pycnofibers, and indeed speaks of them as if they are a real thing that are not just actinofibrils- "pycnofibres have been reported in 28 specimens distributed among 17 pterosaur species, which encompass much of Pterosauria and, typically, are associated with the skull, neck, body and wings", "These tapering, relatively straight and seemingly rather stiff structures, also reported for Batrachognathus volans and seemingly unique to anurognathids, appear to be distinctly different from other pycnofibres. The peculiar branching morphology exhibited by these structures in CAGSâZ070 most likely reflects fraying or the accidental overlap of multiple bristles." Instead, they only argue that "branching pycnofibres in NJUâ57003 and CAGSâZ070, whichâwith one exceptionâare all associated with flight patagia, are most likely misidentified aktinofibrils."
But the Portsmouth press release is titled "Naked prehistoric monsters!" and states the authors "believe they were in fact bald", providing an illustration of a naked Anhanguera next to a feathered one. Then Martill is quoted as saying "And if they didnât have feathers, then how did they keep warm at night, what limits did this have on their geographic range, did they stay away from colder northern climes as most reptiles do today. And how did they thermoregulate?" So what happened here?
Contra the authors, lacking stage II feathers doesn't mean pycnofibers aren't stage I feathers homologous with those of birds. And indeed, arguing pterosaurs were naked when they show the same kind of covering in Jehol deposits that coelurosaurs do (minus the big remiges and retrices) is just as silly as BANDit attempts to discredit dinosaur feathers. Unless all the coelurosaurs' and birds' bodies were just covered in actinofibrils...
Mickey Mortimer
From: dinosaur-l-request@mymaillists.usc.edu <dinosaur-l-request@mymaillists.usc.edu> on behalf of Ben Creisler <bcreisler@gmail.com>
Sent: Monday, September 28, 2020 11:42 AM
To: dinosaur-l@usc.edu <dinosaur-l@usc.edu>
Subject: [dinosaur] "Naked" pterosaurs study challenges feather-like structures on skinÂ
Ben Creisler
A new short paper (2 pages) with no abstract or preview:
David M. Unwin & David M. Martill (2020)
No protofeathers on pterosaurs.
Nature Ecology & Evolution (advance online publication)
doi: https://doi.org/10.1038/s41559-020-01308-9
https://www.nature.com/articles/s41559-020-01308-9
The original article was published on 17 December 2018
Yang, Z. et al. Pterosaur integumentary structures with complex feather-like branching. Nat. Ecol. Evol. 4, 24â30 (2019).
Free pdf:
A Matters Arising to this article was published on 28 September 2020
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Data availability
The data that support the findings of this study were collected from the literature cited and examination of specimens mentioned in the text.
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News release:
Naked prehistoric monsters: Evidence that prehistoric flying reptiles probably had feathers refuted