Re: Evolutionary Stages

Richard Spear (
Tue, 29 Aug 1995 01:58:15 GMT (Kenn Hipkiss) wrote:

>Through evulution confers advantages to the end product of a successful
>evolutionary line, the feature in the intermediate stages can be highly
>counter survival. Example, how does a lizard evolve into a Pteradactyl?
>Presumably it's fingers start to lengthen, as does the extended webbing between
>them until they evolve into foldable aerodynamic wings. Great for the
>Pteradactyl but what about the million years or so that the species passes
>with appendages that are no longer good for normal movement and yet are not yet
>usefull as wings. How do they survive, prey, and procreate during the million
>years in which they are changing?

Ken - the adaptation would not be present (or continue to develop) if
it were *not* advantageous. When changes occur over long periods of
time it is the result of selection and must confer some advantage to
the species.