Re: Pterosaur feathers?

[Waylon Rowley <whte_rbt_obj@yahoo.com>]

> How about just feathers > scutes (and pterosaur fur,
> and stegosaur plates, 
> and psittacosaur quills, and sauropod dermal
> structures, and ankylosaur 
> scutes)? Say feathers arose as hairlike dermal
> structures in Permian 
> prolacertiforms (might have been useful as
> insulation during glacial periods 
> then), then take it from there. 

Ooooor, these tufts on pterosaurs and some dinosaurs
evolved convergently. Both groups could have evolved
these structures from a very similar ancestral scute.
I'm thinking that there may be some reason -genetic or
otherwise- that scutes (when evolving into a more
complex integument) tend to form tufts instead of
simple single-filament affairs. What about mammals?
Does anyone have reason to suspect mammalian hair
arose from scutes instead of scales? 

W.R.   


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