Re: Another feather theory

[Dann Pigdon <dannj@alphalink.com.au>]

On Wed, May 26th, 2010 at 8:46 AM, Phillip Bigelow <bigelowp@juno.com> wrote:

> 
> One hypothesized route to flight:
> 
> 1) Origin of fuzz (small stuff) for display, insulation, etc., NOT
> for protection --> 2) Evolutionary lengthening and stiffening of the
> fuzz into long feathers, in order to give a predator more stuff to
> bite off. --> 3) Later, evolutionary tweaking of the long feathers
> for gliding/powered flight.
> 
> Feathers are perfect for defensive protection because:
> 
> - They are not living tissue.
> 
> - They are light weight (little energy needed
> to carry them around).
> 
> - They are easily removed (less painful or debilitating).
> 
> - They are automatically replaced.
> 
> - They can grow big enough to fool a predator into thinking that it
> has a mouthful of prey.
> 
> 
> So, it is possible that feathers didn't originate for defensive
> protection, but they may have later evolved along that route as an
> intermediate step on the road that eventually led to powered flight.

It certainly sounds plausible - although if feathers were increasing in length 
for the purpose of 
predator avoidance, it could just as easily have been to make the potential 
prey look larger than it 
actually was. Imagine if a small Sinosauropteryx-like theropod puffed out all 
of its protofeathers, 
erected a suddenly bushy tail, and backed up the display with an aggressive 
open-mouthed hiss. It 
might have been enough to make a potential predator (or rival) think twice.

Passive predator avoidance (whereby the predator doesn't attack at all) is 
always a much better 
alternative to active escape mechanisms.

-- 
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Dann Pigdon
GIS Specialist                         Australian Dinosaurs
Melbourne, Australia               http://home.alphalink.com.au/~dannj
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