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RE: Bristles before down: A new perspective on the functional origin of feathers

The argument for this paper is a functional one rather than simply a 
developmental one: bristles as non-concentrated sense or display organs first, 
modified for insulation secondarily.

Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Office: Centreville 1216                        
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
Fax: 301-314-9661               

Faculty Director, Science & Global Change Program, College Park Scholars
Fax: 301-314-9843

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
                        Building 237, Room 1117
                        University of Maryland
                        College Park, MD 20742 USA
> -----Original Message-----
> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] On Behalf Of 
> Jaime Headden
> Sent: Tuesday, March 10, 2015 1:09 PM
> To: dinosaur@usc.edu
> Subject: Re: Bristles before down: A new perspective on the functional origin 
> of feathers
> Also without having read this, I am curious:
> Isn't the "bristle first" argument already the rpevailing theory of the 
> origin of avian feathers? That is, Prum's Stage I, as demonstrated
> in the form of "pycnofibers" in pterosaurs, are a bundle of closely bunched 
> filaments, arranged "en masse." This isn't a problem, if it
> occurs prior to the appearance of feathered dinosaurs, as a precursor.
> It agrees with feather development.
> On Tue, Mar 10, 2015 at 9:10 AM, Ben Creisler <bcreisler@gmail.com> wrote:
> > Ben Creisler
> > bcreisler@gmail.com
> >
> > A new online paper:
> >
> > W. Scott Persons IV and Philip J. Currie (2015) Bristles before down:
> > A new perspective on the functional origin of feathers.
> > Evolution (advance online publication)
> > DOI: 10.1111/evo.12634
> > http://onlinelibrary.wiley.com/doi/10.1111/evo.12634/abstract
> >
> > Over the course of the last two decades, the understanding of the
> > early evolution of feathers in non-avian dinosaurs has been
> > revolutionized. It is now recognized that early feathers had a simple
> > form comparable in general structure to the hairs of mammals. Insight
> > into the prevalence of simple feathers throughout the dinosaur family
> > tree has gradually arisen in tandem with the growing evidence for
> > endothermic dinosaur metabolisms. This has led to the generally
> > accepted opinion that the early feather coats of dinosaurs functioned
> > as thermo insulation. However, thermo insulation is often erroneously
> > stated to be a likely functional explanation for the origin of
> > feathers. The problem with this explanation is that, like mammalian
> > hair, simple feathers could serve as insulation only when present in
> > sufficiently high concentrations. The theory therefore necessitates
> > the origination of feathers en masse. We advocate for a novel origin
> > theory of feathers as bristles. Bristles are facial feathers common
> > among modern birds that function like mammalian tactile whiskers, and
> > are frequently simple and hair-like in form. Bristles serve their role
> > in low concentrations, and therefore offer a feasible first stage in
> > feather evolution.
> --
> Jaime A. Headden
> The Bite Stuff: http://qilong.wordpress.com/
> "Innocent, unbiased observation is a myth" - P. B. Medawar (1969)