[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Yet more on dinosaur quad climbers

> Date: Fri, 12 Jul 2013 20:05:52 -0400
> From: ruben@mrbrklyn.com

> On Fri, Jul 12, 2013 at 02:51:22PM -0700, Mike Habib wrote:
>> On Jul 12, 2013, at 2:31 PM, Ruben Safir <ruben@mrbrklyn.com> wrote:
>>> Also, for almost all birds, at breeding season, the beaks turn color
>>> but to imply beaks evoloved for dispaly makes as much sense as flight
>>> feathers.
>> This argument makes no sense to me. Sure, the ancestral function of beaks is 
>> probably mostly feeding. But beak *color*, which is what you are 
>> referencing, probably did evolve under a largely display-oriented context. 
>> Besides, I never said that flight feathers evolved "for display". I merely 
>> pointed out that modern birds regularly use the wings for non-flight 
>> functions. That is all.
> You didn't write this?
> "but this does not mean that those effects were the primary function or
> that the limbs were used for a sustained flight function (or, indeed, a
> lift dominated function at all - though it is likely they were)"

 what does that have to do with beak coloration?

> That flight feathers would have evolved for anything other than flight
> would be an extradonary hypothesis that would need extradonary evidence.
> To repeat, having long light weight planar kites attached to ones arms
> would have an extremely debilitating effect of any other use of the
> arms... other than flight.

 That reminds me of a question posed to me once... "how can a turtle pull its 
head into a protective shell, before its evolved a [complete] shell?"