Re: Flying Along a Logarithmic Spiral

[brian whatcott <inet@INTELLISYS.NET>]

It would be hard to find anyone who doubts the short term importance
of inheritance vs. environmental factors - for humans this is often
estimated at 70:30%

 The natural selection argument holds that if a range of natural
variation exists in a particular design of creature or plant, then the
design variety that best fits the environment where survival and
propagation themselves are problematic, will flourish (in comparison
to others).    If environmental challenges change over a similar time
scale to the generation time, then this favored aspect is evanescent.

   But what if a creature has proven well adapted to a succession of
challenges over many millions of years?
 There is a suggestion that some species have limited resources left with
which to generate the varied types on which selection operates - despite
some mechanisms thought to allow renewed variation (though preponderantly
 deleterious like radiation induced damage).
It may be this kind of limited variation that Jack is pointing to, when
he says, "Look a predator may have some behavioral character because
 some other related species seperately existing for many millions of
years can be seen to have a comparable behavior."

 I feel unsure of the ethological evidence for this position, if it is
in fact what Jack has in mind - but I and I'm sure, he is  aware of
the biochemical pathways shared by living organisms seperated
 by eons - yeasts and humans for example. There, there are molecular
biochemical markers that may be compared in a rather objective way.
 As always, behavior is harder to evaluate.

Brian


At 22:47 12/20/00 -0600, Jack Uretsky offers this:

> Hi all-
>        Maybe it's inheritance rather than optimization.  I was watching
> a piece on <how to tickle an alligator> the other night.  The advice is,
> approach from straigt ahead - an alligator always strikes on a diagonal.
> So alligators and birds are cousins, right?  Both are dinosaur relics.
> So why shouldn't they have features in common that are inherited, rather
> than adaptive?
>                                        Regards,
>                                                Jack
> >
> On Wed, 20 Dec 2000, brian whatcott wrote:

> > /snip/: "if evolutionary design
> > efficiencies are so darned effective at optimizing a design, why
> > isn't the direction for maximal acuity situated straight-ahead anyway?"
> >  - for example. The general design layout for the bird has been around
> >  an exceptionally long time - and even a novel construct like the mammal
> >  can fine focus nearly straight ahead, can't it?
> >
> >  This suggests there are competing objectives involved - indeed Bill
> > mentions head streamlining versus light gathering (where the Owl seems
> > to have been optimized for rather different visual/flight conditions
> > as an airborne predator.)  I expect that birds in general have the
> > built in capability of "keeping your head on a swivel!"
> >  - the advice given to novice pilots... by its panoramic view which is
> > not apparently optimized for binocular fusion and depth perception by
> > this means.
/snip/
> > Brian

brian whatcott <inet@intellisys.net>  Altus OK
                Eureka!