[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

re: Feduccia discussions



How about this for a possible scenario?  A small (theropod) dinosaur
discovers that prey localization and capture is facilitated by perching on
low-lying vegetation or low tree branches.  Pouncing accurately on
a moving ground-level prey from such a location would require a good
level of aerodynamic control (pitch, yaw, roll, etc.)  Getting back up into
the bushes or low tree branches would require the ability to generate lift.
Such a creature would never have a purely gliding stage, and would
have to develop both control and lift capabilities simultaneously.  This
idea reminds me of Caple's arguments for the cursorial origin of flight, but
turns it around.  Caple suggested that a running bipedal animal would
leap for airborne prey, requiring the ability to generate lift on the way up
to the prey and the ability to control movement through the air and make a
bipedal landing.  The idea I have suggested above would apply to an
animal that needs control on the way down to its prey, and lift to get
back up to its perch.  Lift and control could co-evolve in the forelimb, and
the hindlimb could make the transition from a cursorial configuration to a
grasping one simultaneously.  

Reactions from the group?

James

James M. Norton, Ph.D.
University of New England
11 Hill's Beach Road
Biddeford, ME  04005
phone: [207]283-0171 x2270
fax: [207]283-3249
email: jnorton@mailbox.une.edu