I'll agree and disagree with Art. I agree that just doubling of the
chromosomes may not really be an increase of information. Sure it results
in a new species but our definitions of species are such a contrived thing
anyway. More work needs to be done on these critters but it may be that
they have derived a complex system to deal with the problems of being a
tetraploid. They did overcome the problem of have doubled sex chromosomes
somehow. My point really isn't about the doubling of the genetic
information but the difficulty in pulling off this feat. I suspect that
before any cases of polyploidy in mammals had been found some could have
suggested in was impossible but despite the extremely remote chance of it
occurring it apparently has (unless these are a separate rat kind of some
sort that just happens to look like other rats). It just shows that
things that seem extremely unlikely still do occur and we shouldn't be too
quick to make bold statements that this or that couldn't have occurred.
Joel
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R. Joel Duff, Assistant Professor
Dept. of Biology, ASEC 185
Campus Mail 3908
University of Akron
Akron OH, 44325-3908
Office: 330-972-6077
rjduff@uakron.edu
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