attached mail follows:
David Campbell wrote:
>
> >There are a big bunch of chickens and the foxes are eating them. Over
> >time there will be some microselection as the gene frequencies are
> >modified and those with longer legs are seen to dominate the population.
> >
> >Now tell me as to "inventive macromutations":
> >
> >Will the chickens develope teeth as a defensive mechanism?
> >
> >Will they develop an eye in the back of their head?
> >
> >How long will it take given the number of chickens, foxes, etc.?
> >
> >What does the ratio of chickens to foxes have to be at t=0 so that the
> >chickens do not go extinct? Or, that there become too few chickens so
> >genetically produce an effective mutation rate?
> >
> >What will happen, and incidently, I will give you as accurate a
> >description of the initial conditions of the chickens as you want, why,
> >you can even be given the total genetic code of the chicken, mutation
> >rate, etc. Just tell me what you want to know and in fact please assume
> >that you have all the information you want at time zero.
> >
>
> It may in part reflect a Calvinistic viewpoint, but assuming that we knew
> exactly what gene did what, what the effect of each mutation would be, the
> relative benefits and costs of each change, and what mutations would occur
> (e.g., exactly what bases would get hit by a cosmic ray or be miscopied,
> etc.), I think it would be possible to predict the evolution. God, being
> omniscent and omnipotent, can bring about exactly what He wants through
> such a process even though it is practically unpredictable to us.
>
> Speculation on what could happen:
> Escape seems to be a more frequent adaptation than sharp teeth for defense,
> so better wings or longer legs seem more likely. Sharp teeth might also
> interfere with eating grain and bugs. There was a paper several years ago
> claiming to have gotten a chicken tooth gene to work; however, it was
> questioned whether their protocol was adequate to ensure that the
> tooth-making gene really came from the chicken.
>
> Instead of an eye in back, moving eyes from the front towards the side of
> the head does occur. This gives closer to 360 degree vision but less
> binocular vision. I believe woodcocks have about a 340 degree view without
> turning their heads, for example. I would guess that the ability to turn
> one's head or turn around does a good enough job, and eyes in the back of
> the head would not be greatly favored.
>
> At least one bird has developed poison as a defense. Getting very big is
> another possibility. A hyperactive thyroid is the major difference between
> a wolf and a dog, a pigeon and a dodo, or a Canada Goose and the giant
> extinct flightless goose of Hawaii. It is a bit like Peter Pan, never
> growing up in certain respects. Obviously, this is not an advantage
> against human predators, as the last two examples show, unless we figure
> out that domesticating them will ensure a continual supply. A giant fuzzy
> flightless chicken might be a challenge for foxes, though, and requires
> only a little mutation.
>
> If you started with colorful chickens, mutation to a more camoflaged
> pattern might be favored and relatively easy.
>
> There is the old tall tale of someone who liked drumsticks and developed a
> three legged chicken. They ran too fast for him to catch, however. Maybe
> that's the next big mutation :)
>
> A problem in communication here is the definition of a major mutation. A
> slight change in a gene involved in early development could have a big
> effect on the final appearance, whereas extensive mutation of another gene
> might have little or no morphological effect. For example, the living
> Hawaiian goose, the Nene, does not look all that different from a Canada
> Goose, yet it split off earlier than the giant flightless goose. The
> flightless goose had a mutation with bigger effects on appearance than did
> the Nene, despite having less time.
>
> David C.
***********
Your prediction is not precise enough to allow for any kind of testing
of the actualy outcome vs. the forecast. Bert M.
This archive was generated by hypermail 2b29 : Fri Jan 14 2000 - 10:35:49 EST