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

That IS basically their argument. Bristles (for sensory or display function), 
modified by density & structure for insulation afterwards.

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 
> Ronald Orenstein
> Sent: Tuesday, March 10, 2015 12:18 PM
> To: bcreisler@gmail.com; dinosaur@usc.edu
> Subject: Re: Bristles before down: A new perspective on the functional origin 
> of feathers
> Without reading the paper: cannot a covering of bristles, even if not dense, 
> provide some thermoregulation by creating a boundary air
> layer near the surface of the skin?
> Ronald Orenstein
> 1825 Shady Creek Court
> Mississauga, ON L5L 3W2
> Canada
> ronorenstein.blogspot.com
> ronorensteinwriter.blogspot.com
> ________________________________
> From: Ben Creisler <bcreisler@gmail.com>
> To: dinosaur@usc.edu
> Sent: Tuesday, March 10, 2015 12:10 PM
> Subject: Bristles before down: A new perspective on the functional origin of 
> feathers
> 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.