Re: Gliding vs Non-gliding

["Tim Williams" <twilliams_alpha@hotmail.com>]

Marcel Bertolucci wrote:

>     As I can see, the biomechanics of mammals and reptiles differ from one
> another, mostly because of the metabolism and the energy necessary to
> biomechanics of flight.

Gliding requires very little energy on the part of the glider.  Almost none 
at all in fact, except during maneuvering and landing.

Unlike gliding, powered flight requires a LOT of energy.

> That's maybe why mammals do have representatives
> that fly and others that glide, and the reptiles may only glide.

There is only one group of flying mammals (Chiroptera / bats).  There are 
*two* groups of flying vertebrates which evolved from reptiles (or amniotes 
usually termed reptiles): birds (from theropods) and pterosaurs (from 
prolacertiforms or basal archosaurs - after reading Peters (2001), I like a 
prolacertiform ancestry better.)





Tim

------------------------------------------------------------

Timothy J. Williams

USDA/ARS Researcher
Agronomy Hall
Iowa State University
Ames IA 50014

Phone: 515 294 9233
Fax:   515 294 3163

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