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Re: BAAD BCF



In a message dated 95-12-01 13:13:05 EST, ornstn@inforamp.net (Ronald
Orenstein) writes:

>Certainly "useless random" fluttering would not happen.  But I think it is a
>valid question to ask how the use of a power stroke evolved, and
>non-useless, directed fluttering might have been involved.  As living
>animals show an efficient glider can travel huge distances.  Why go to the
>more energetically-expensive powered flight option?
>
>I am only suggesting (hypothesizing, guessing) that this step would not have
>been taken by an efficient glider trying to extend its range or degree of
>control, but by a non-glider seeking to add a little more power to its
>upward leaps.  Thus  an animal in a tree seeking to reach a limb (say) two
>metres or so over its head could not glide to it, but could leap for it -
>and a fluttering stroke may have given it a little more ability to
>accomplish the leap successfully.  If this is true the evolution of powered
>flight has nothing to do with gliding - indeed an accomplished flutterer
>could add gliding to its repertoire later, rather than the other way round.

You have a very good point here: Powered flight may have arisen among lousy
gliders rather than good ones; both good gliding and powered flight might be
considered improvements over lousy gliding, but going in different
directions.