Again, not species-creating changes.
Certainly it's an example of natural selection but not the macro-evolution
which is what I was describing as really fascinating.
I wonder if the initial gene pool already included the beak variations. In
that case all you've got is a shift in the proportions within the gene pool.
James
----- Original Message -----
From: "Dave Winer" <dave@userland.com>
To: "James Tauber" <jtauber@jtauber.com>; "FoRK" <fork@xent.com>; "Antoun
Nabhan" <antoun@incellico.com>
Sent: Friday, April 20, 2001 10:34 PM
Subject: Re: Evolution being slow ...
> 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
> > >
> > >
> >
>
This archive was generated by hypermail 2b29 : Sun Apr 29 2001 - 20:26:03 PDT