RE: Gliders to Fliers? (Was Re: Ruben Strikes Back)

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> dbensen
>
> >>There are too many "perhaps this" and "perhaps that" arguments and
> counterarguments in this issue. Not enough constraints to settle the
> question, certainly not enough constraints to reject any reasonable
> hypothesis.<<
> I agree completely.  Sombody needs to do some locomotion work
> like Bakker did
> with the crocodiles.  Maybe the most constructive outcome of
> Gliders to Fliers?
> could be a list of all the things we need to study to get an answer.

Agreed.

In fact, people ARE studying it (see my posts from January re: the SICB
meetings, among others).

The mechanics of gliding, of take off, even many aspects of running are MUCH
LESS WELL UNDERSTOOD than people here (and elsewhere) think.  For example,
many people have assumed gliding begins by dropping from trees/cliffs.
Sorry: laboratory experiments show that gliding animals (including flying
squirrels and even flying snakes!) begin with a propulsive phase: they jump
first.

There is a growing body of literature dealing with the mechanics of
locomotion in modern animals: Steven Gatsey & his students represent one
important lab for that work, for example.  Some (Gatsey again) are
interested in questions related to the origin of flight.

At present, although powered flight is fairly well understood (due to
Rayner, Goslow, Dial, and colleagues) the other half of the equation
(gliding) is not.


                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796