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Re: New Burnham Book



Mark Pauline <markpauline@rocketmail.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
> Microraptor. 


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 
the other.


Cheers

Tim