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Re: Feathers and scutes



REPLY: Alan Brush and Richard Prum have a forthcoming
collaborative paper -- which should be a landmark in
cumulative research on the subject -- fully
explicating the origin and relatedness of feathers,
and clarifying functionality of various types.
Feathers are, in my mind, a significant "evolutionary
novelty" in dinosaur phylogenetic systematics,
especially when one considers: 1) how various writers
throw the word "flight feathers" in the air without
realizing the connotations (and biomechanics); 2) how,
among all extant theropods, feathers have a stunning
array of forms and functions (cf. the hair-like
structures of the kiwi, the sexual displays of
peacocks, etc.). Dromaeosaurs flew -- now, we have to
carefully consider how a dromaeosaur without wings,
but feathers on its arms, could achieve it.
*******************************************************
--- Brian Lauret <zthemanvirus@hotmail.com> wrote:
> 
> I seem to remember a study indicating feathers and
> scutes are from the same 
> genetical composition.Could this mean they were
> interchangeable? it could 
> certainly indicate why large dinosaurs had scutes
> instead of feathers. The 
> genes involved in the development of these
> structures could possibly produce 
> feathers and scutes.(and who knows what other
> structures?stegosaur 
> plates?psittacosaur quills?remember the fact that
> Anhima has a remarkable 
> sort of "horn" on it's head,could this be from the
> same origin as feathers 
> and scutes?) This means it's a genetical "choice"
> between feathers and 
> scutes.This would certainly explain how come snowy
> owls and snowgrouse (as 
> well as certain chickens and canaries) have feathery
> feet instead of 
> scutes.The genes translated structures normally
> developing into scutes in to 
> growing feathers because that was better in these
> hostile enviroments. (or 
> according to human selection)I guess vice vera might
> be possible too.(Any 
> canary or chickenbreeders onlist??)I surely think it
> would be cool to see a 
> scuted instead of feathered bird!
> Oh well,shoot me if you like
> Brian
> 
> 
> 
>
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