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Re: New Burnham Book
Mark Pauline <email@example.com> wrote:
> "Eventually, birds of modern
> aspect probably replaced the primitive maniraptorans since
> they were
> more efficient fliers and had evolved higher metabolic
> rates suitable
> for the cooler climate."
> -By "eventually" Burnham must mean "already", since
> carinate birds had already diversified by the time of
Exactly. Plus, there were small, feathered, and possibly winged paravians near
the end of the Cretaceous - such as _Mahakala_ and _Rahonavis_. Why couldn't
these have been four-winged gliders? Or two-winged gliders? Maniraptoran
gliders might have persisted until the very end of the Cretaceous. Even if
maniraptoran gliders did go extinct in the Lower Cretaceous, it does not
necessarily mean that birds were to blame.
And why would gliding maniraptorans have been "replaced" by "birds of modern
aspect"? In the modern world, bats co-exist quite happily with different
species of nocturnal gliding mammals. The advent of powered flight does not
necessarily make passive gliding redundant.
Burnham's work contains so many unfounded assumptions, stacked one on top of