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Re: pterosaurs & snakes
>From: Robert.J.Meyerson@uwrf.edu (Robert J. Meyerson)
> As they got rid of their tail, however, the became far less stable in the
> air. It was for this reason, that most pterodactyloids have crests on the
> head; it serves as a rudder while in flight.
The main evidence *against* this position is the fact that the
size of the crest is sexually dimorphic in Pteranodon.
[Male Pteranodons have larger crests than females of the same speces].
Also, most small pterodactyloids *don't* have a crest (for instance,
Pterodactylus itself has no crest).
Thirdly, some of the crests are very small - especially some of the
nasal crests, as in some of the South American genera.
I know it may begin to sound like a broken record - but I see
more evidence for a display function than an aerodynamic one
for these crests.
The peace of God be with you.