Re: _Archaeopteryx_ and the Evolution of Bird Flight

["Matthew Troutman" <m_troutman@hotmail.com>]

<<Shipman, Pat. 1998.  _Taking Wing: *Archaeopteryx* and the Evolution 
of Bird Flight_. Simon & Schuster, New York. ISBN 0-684-81131-6.>>

It is a very good book,  and somebody who doesn't know their stuff on 
bird origins should look at it.  However, where Shipman makes a mistake 
is her account on the arboreality of Archaeopteryx; she interprets that 
since Archaeopteryx lacks a zygodactyl foot and large flexor tubercles 
on the pedal phalanges as evidence against the arboreality of 
Archaeopteryx.  Many birds such as woodcreepers are trunk-climbers and 
lack zygodactyl feet, and Archaeopteryx does seem to have enlarged 
flexor tubercles on its pedal phalanges.  She also brings up the 
supposed "problem" with the lack of the appropriate vegatation for 
climbing.  Gingkos have been found in the Solnhofen limestones, and they 
are more than suitable trees for climbing.  Plus, even if the coniferous 
stem succulents were not that tall, many birds can live in scrub like 
that ( such as the elusive saige wren that lives in prarie grasses and 
praries, scarsely flying above 10ft above the ground ).  Shipman also 
fails to recognize that some lineages of theropods may been arboreal 
and/or from arboreal ancestors.  She also ignores the clear evidence 
that Archaeopteryx and early birds could not take off from the ground 
because the M.supracoracoideus was not developed to perform a complete 
upstroke.  She claims that the crowd in support of the arboreal origin 
of flight is a "minority of experts who do not hold to the theropodian 
ancestry of birds".  Wrong!  Larry Witmer and Sankar Chatterjee are 
supporters of this idea or are sympathetic to the notion.  Plus, I'm 
looking into the arboreal origin ( cannot say more ).  

Overall, the book is good and anybody interested in birds or dinosaurs 
should look into it.  Shipman's chapter on the history of Archaeopteryx 
and her look into the Fred Hoyle accusations are very good.  

Matt Troutman

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