Corn as evidence of macroevolution (Doebley, Iltis, et.al.)?
Doug_Ee at um.cc.umich.edu
Thu Dec 16 11:39:45 EST 1993
In article <2ejikt$q9e at bardeen.physics.csbsju.edu>
A la vida, ddackerman at tiny.computing.csbsju.edu writes:
>I would just like to pose a question, and that is what researchers hear think
>of the idea of macroevolution and such. Especially, I am interested in
>what people think of corn (Iltis's C.S.T.T. or the recent Science article on
>gene locus tg1 [spelling?]) as an example of macroevolution.
As an off-the-cuff response, you may want to distinguish between
two concepts: 1) "macromutation" includes many varieties of mutations
except for the long-known point- or frame-shift ("micro") mutations; and
2) "macroevolution" in which one is hypothesizing that species
are evolving through time in a way that is decoupled from "microevolution,"
or _any_ change within a single population or species. This gets into
debate about whether or not there are "emergent" properties of species.
Do we gain anything by distinguishing the organismal level at which
selection occurs among individuals (microevolution) from the level
at which selection occurs among species (macroevolution)? As far
as I know, paleontologists such as Steve Stanley and S. J. Gould have
been the chief proponents of a macroevolutionary view, but this doesn't
have much to do with the magnitude of a mutational event.
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