Re: Tiktaalik

[David Marjanovic <david.marjanovic@gmx.at>]

> > Well, _actually_, that _is_ a small (though of course rare) change that
> > just _looks_ like a big one morphologically.
>
> Yes.  It looks like a big morphological change, because it *is* a big
> morphological change.  Sure, it was caused by a small developmental 
> change;
> but it's the resulting phenotype that's acted upon by natural selection.

It's just one mutation, it seems. BMP2 gets expressed in a place where it 
usually isn't.

The nice thing about mutations is that they _can_ be quantified -- counted. 
:-)