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Re: More on the genus problem

I think also that the biological species concepts, related to
delimitation of gene pools, are neither used to refer a given
individual to a species today, and you rather employ morphology,
behaviour, songs, etc. In order to confirm contribution to the same
gene pool, you should have a living holotype and prove if an
individual you collect can have fertile offspring with it (at least
conforming to the laboratory definition: this may imply we will likely
few times be sure if a given individual contributes to the wild gene
pool) -continuing this absurdity, given that the holotype will
sometime die, you will have to clone it regularly-.

Our morphological ways of referring living individuals to species (as
most noeontologists and birdwatchers do) are just approximations to
what we think the member of a given gene pool looks like. Of course,
this implies great chances of being wrong. So, given that we will not
go around looking at if the live specimens we collect contribute to
the same gene pool, laboratory and wild, we should neither talk of
species assignments to these living beings.

Thus, with specimens for which we only have information different from
contributing to gene pools, we should neither speak of species, either
if living or fossil. We should conform to assing it to clades
irrespective of ranks, as David said. The only way we may meaningfully
talk about species may be if we are studying gene pools, reproductive
dynamics of populations, and studies derived from these, and even in
that case, species may nearly come to only represent a synonym of gene
pool, and would thus be more likely be superfluous (and may be
eliminated, because of the ambiguity carried by the many concepts with
which it was associated; alternatively, it has priority over gene
pool, so I do not know...).

I think the only thing we can do with morphology is cladistic
classification. Clades do not necessarily have to do with gene pools,
and a given gene pool not necessarily has to coincide with a
monophyletic group, and may conceivably be paraphyletic or, less
intuitively, even polyphyletic (why not?). As long as we are not able
to trace any correspondence between morphologies and pertenence to
given gene pools, and difference with other gene pools, we should more
profitfully abandon any reference to gene pools (and the special rank
"species" asociated with it) in morphological studies.

PS: Thanks David for the citations on the PDI.