Re: [asa] Genetic Surprise Confirms Neglected 70-Year-Old

Evolutionary Theory
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>
> *Genetic Surprise Confirms Neglected 70-Year-Old Evolutionary Theory*
>

I'm not sure it's quite as neglected as the story makes out. I remember
from a biology class mention of mice in isolated valleys in Italy.
Chromosomal rearrangements (mostly fusion or division) made the
populations
in different valleys reproductively incompatible with other populations,
because the mismatched chromosomes did not sort themselves out
properly in
meiosis. A similar factor often underlies the isolation of new hybrid
species from both parents. If both sets of chromosomes are treated
like a
single set, the hybrid functionally has about twice as many
chromosomes as
either parent and can't interbreed. However, if it is able either to
reproduce asexually or to get together with another hybrid, then it
can be a
self-propagating new species. This is fairly common in plants
(significantly in some crops like wheat and corn).

  --
> Dr. David Campbell
> 425 Scientific Collections
> University of Alabama
> "I think of my happy condition, surrounded by acres of clams"
>

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Received on Sat Sep 9 15:43:00 2006