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Re: Dinosaur Revolution Review
Am 16.09.2011 05:45, schrieb Anthony Docimo:
> While the lack of scale plasticity in extant birds may very well be
> a derived trait, I still can't help but wonder about the old "party
> line" regarding why scales were lost in the first place (i.e. the
> weight reduction hypothesis). With the exception of osteoderms,
> scales are not that heavy. Birds get away with flying around with
> all kinds of strange display structures that would weigh more than
> a light covering of scales would.
Some might argue that that is what birds can afford to do, after they
first got good at flying around.
You can put carpets and chairs in modern planes (even small ones),
but the Wright Flier had to watch how much material it took on
But birds didn't lose their teeth when they started to fly. They lost
them later, and several times independently. The loss in the ancestors
of Neornithes may in fact have been the last one and apparently happened
in the Late Cretaceous (using the oldest occurrences of Ichthyornithes,
the closest relative of Neornithes with known jaws, to estimate the age
of the MRCA of Ichthyornithes and Neornithes).