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FW: The birds vs. the pterosaurs



It may also be noted that pterosaurs were, after all, reptiles.  Not really
having the ability to survive climatic changes as well as an animal with
even rudimentary fur or, in this case feathers, would put a fundamentally
severe strain on their ability to compete with a smaller, faster, perhaps
much more maneuverable creature.

-----Original Message-----
From: Henri Rönkkö [mailto:henri.ronkko@kolumbus.fi] 


Hi!
 
Steve Doolittle wrote about the demise of the pterosaurs:
 
"Which brings me to this question:  If the dinosaurs evolved into birds, why
did they do that when that ecological niche was already filled by the
pterosaurs?  Because they could do the flying thing better?  Maybe the birds
filled a niche that the pterosaurs couldn't?"  

Well, I don't think the first of the birds competed with the big pterosaurs.
I don't believe that competition with birds drove the great, soaring
pteoraurs such as Pteranodons to extinction. It is probable that Pteranodon
and friends couldn't do well in a very wide range of environvents, due to
their aeriation style. So when the winds started blowind a little harder,
they were chained to the coastal cliffs and caverns and starved. Soaring
birds evolved after this great dying. The birds living simultaneously with
pterosaurs wouldn't have had kids capable of competing well enough with the
great dragons of the air. This is because adaptive evolution consists of
accumulating unidirectional bits of little, undirected and aimless, random
change. The offspring of the ancient birds could be obly a little different
from their parents not adapted to soaring, and so they couldn't compete with
the pterosaurs. Soaring birds didn't evolve, because the creatures giving
birth to the intermediate forms were never born.

"So what the hell happened to the little pterosaurs?  If they were being
"phased out" by the dominance of the birds, why didn't they fill another
niche?  I mean, the dinosaurs did it."
 
I think feathers proved to be better than leathery wings for flapping
flying. The ability to walk well on land may also have played some role.
 
As for why the pterosaurs didin't fill another nice, the only and obious
explanation coming to my mind is that no immediate offspring of a little
pterosaur could compete successfully with creatures of other niches. Empty
niches probably weren't filled, because the pterosaurs trying to live
differently from their parents did even worse.
 
Well, as it is said, that's my two cents.
 
Best wishes,
Henri Rönkkö