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Re: Long, long last gasp. (fwd)



John Bois (jbois@umd5.umd.edu) wrote:

<Further, Q. appears to me to be singularly poorly designed for nest
defense!>

  Could I ask your reasons?
 
<Bats are easy targets for diurnal birds in the daylight--I don't think I
can find the ref. but some sinister researcher released bats in the
daylight. They scrambled for cover but nevertheless many of them were hit
by kookaburra.>

  Ooo. Kookaburra are nasty birds altogether and highly territorial, so no
wonder. Try this in North America, or Europe.

<They diverged before advent of feathers.>

  I'm better than you cause I'm feathered! Ooo, you have hair, oo you must
be better than me. Oh, my, your brain in two cc's larger than mine, I'm
stupid and you win.... These kinds of arguments have fallen by the wayside
many a time as they do nothing but lean to strawmen. Evidence in
pterosaurs, as in the advent of _hair_ (having been the accumulation of a
sort of pelage, structurally unknown to date whether "hair-" or
"filoplume-like") apparently occured in the Triassic/Jurassic welllllllll
before the advent of feathers. Suggesting exaptively high metabolism in a
small animal, especially a flier, should have led, in the frame of the
leading hypothesis, to a better flier, and therefore should have kept the
birds down. Not so.

<What would one look like?  An pterosaur-ostrich?  A bat emu?  Stuff of
nightmares, maybe.  Not reality.>

  Potentially, a flightless bat can occur, as much as a flightless
pterosaur. Needn't be a ratite-knockoff. Reduction in wings, enlargement
of the dorsal vertebrae, pelvis and hindlimb architechture to support a
more terrestrial environment, possible advances to permanent
quadrupedality or bipedality will lead to exaptation and expansion of
things like tails, vertical dorsum, shorter arms and fingers, etc. Should,
possible, but not known and therefore highly hypothetical.
 
<"Similarly `Zhelestidae', an abundant element of Middle Asian coastal
plains since possibly the Cenomanian, gave rise to more derived archaic
ungulates (`condylarths') in North America after arriving there in the
late Santonian." From: Averianov, A O. , and J. D Archibald 2003 Mammals
from the Upper Cretaceous Aitym Formation, Kyzylkum Desert, Uzbekistan.
_Cretaceous Research_, Volume 24, Issue 2 , April 2003, Pages 171-191.>

  Some recent arguments favor use of "Zhelestidae" as a paraphyletic grade
of basal eutherians, and the same is true for "Condylarthra" being the
paraphyletic grade of ungulate-like, carnivore-like etc. higher
eutherians, that gave rise to carnivorans and ungulates, among other
groups. Currently, Zhelestidae does not seem to be favored as a natural
grouping beyond *Zhelestes,* and Condylarthra was used in the quote above
_in_ quotes, leading to the paraphyletic nature now regarded as more real
than not.

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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