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Date: | Fri, 8 Jul 2005 11:06:57 -0400 |
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"Manuel J. Tenorio" wrote:
>
> The big
> (unanswered) question is therefore, which is the threshold in DNA
> differences for species separation?
* the even bigger quaetion is whether it's right to use levels of
phentic or genetic difference to define species. If species are defined
by reproductive isolation, then the only criterion is whether they
intergrade when they naturally come into geographic contact. It
shouldn't matter how different they are: as long as they form a single
population when they're in contact they're the same species - and
likewise it doesn't matter how similar they are - if they don't
interbreed they're different species.
I don't know about Conidae, but there's a tendency in Vertebrate
stystematics to observe the degeee of genetic difference between 'good'
species, and then to impose this statistic as a criterion of specieation
even when the repoductive evidence is missing or opposed.
fred.
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Bishops Mills Natural History Centre
Frederick W. Schueler, Aleta Karstad, Jennifer Helene Schueler
RR#2 Bishops Mills, Ontario, Canada K0G 1T0
on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
(613)258-3107 <[log in to unmask]> http://pinicola.ca
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