Actually, I hear, under some circumstances, evolution is very fast.
Someone did a study on the Galapagos with some kind of bird that adapted,
through evolution, to changing food supply.
After a few generations, just a few years, they had longer beaks and shorter
toes, or something like that.
I saw a PBS special on it some years ago.
Dave
----- Original Message -----
From: "James Tauber" <jtauber@jtauber.com>
To: "FoRK" <fork@xent.com>; "Antoun Nabhan" <antoun@incellico.com>
Sent: Friday, April 20, 2001 6:16 PM
Subject: Re: Evolution being slow ...
>
> Yes, you're right of course. But they are hardly species-creating changes.
I
> should have been clearer: I was talking about macro-evolution (going way
> back to prebiotic), not improvements within a species.
>
> If you take the changes necessary to take a mouse's genotype to a human's,
> how many of those changes are individually beneficial?
>
> James
>
> ----- Original Message -----
> From: "Antoun Nabhan" <antoun@incellico.com>
> To: "James Tauber" <jtauber@jtauber.com>; "FoRK" <fork@xent.com>
> Sent: Friday, April 20, 2001 7:23 PM
> Subject: Re: Evolution being slow ...
>
>
> > At 06:36 PM 4/20/01 -0400, James Tauber wrote:
> > >One thing that has always fascinated me is the number of genotypic
> mutations
> > >that need to take place for the phenotype to have a beneficial change.
> It's
> > >not as if a single change to the DNA has an immediate benefit. You
really
> >
> > Huhwhat? There are Single Nucleotide Polymorphisms - one-base changes -
> > that account for significant phenotypic mutations like Huntington's
> Disease
> > and increased resistance to certain cancers. Likewise, a change in a
> > limited number - frequently 13 or fewer bases appear to account for
> > differences in "Continuum Traits" like blood pressure and ability to
> > metabolize cholesterol. So maybe there's a big probabilitistic
> > concatenation to get from a mouse to a human, but to get from an early
> > human to a healthier, stealthier human isn't necessarily so improbable.
> >
> > I'm not a bioinformaticist, but I play one at conferences,
> > --Antoun
> >
> >
>
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