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Index][Thread Index][Subject Index][Author Index] Re: NO
SECONDARILY FLIGHTLESS THEROPODS ><< I do not see why a more "
primitive " species cannot evolve > flightlessness in the same
way that modern species do. >> <<They may, or they may not;
they're certainly not >obliged< to. By the way, I find your
posts on paedomorphosis in the evolution of flightlessness quite
interesting. Please keep them coming; you have a good command of
the material.>> Thanks for your interest and the compliment.
But, there is a possibilty that they _are_ obliged to. Now among
vertebrates that fly, as far as is known, only birds have become
flightless. What makes them special in this regard? The answer
is rather obvious : birds are an extremely adaptable group of
vertebrates that are able of equal locomotion on ground, sea, or
air. But, even some birds that live on ground or in the sea do
not show progressive trends toward flightlessness. The factor
which turns a bird flightless i