I got an e-mail asking why I thought interbreeding between European polecats
and ferrets wasn't enough evidence to assume they are the same species.
Easy, because the ferret can also interbreed with Mustela erminae, AKA:
Stoat, Ermine.  The hybrids are reportedly fertile.  (Check out A.P.  Gray
1954 "Mammalian Hybrids").  If successful interbreeding producing fertile
offspring is all you need to prove two animals belong to the same species,
then the European Polecat and the Stoat are the same species.  (Same with
the lion and tiger, the housecat and bobcat, the wolf/dog/coyote, etc.)
Before you ask, I don't know if the stoat can interbreed with the European
polecat; just because the ferret can crossbreed with the two isn't evidence
they can.  Deer mice span the entire USA, and the east coast variety can
breed with the mid-western, who can breed with the westerners, but the east
coast and west coast mice cannot.
 
The evidence for the polecat and ferret being the same species (the ferret
being the domesticated version) are similar morphology, chromosomal
structure, and interbreeding.  The morphology can be explained by looking at
all polecats--they ALL look the same, and ferret coat color is determined at
the whim of humans.  (I have seen ferrets that are spitin' images of the
BFF).  The chromosomal structure can be explained by the two species having
a common ancestor in the recent past ( a protoferret giving rise to two
lineages, one becoming the European polecat, the other becoming the ancestor
of the domesticated ferret).  After all, just because the steppe polecat has
2n=38 chromosomes, and the ferret has 2n=40, doesn't mean the steppe polecat
couldn't be the ancestor; a mutation could have occured during the
domestication process, which caused an increase in chromosomes.  Thats
probably what happened when the European polecat evolved from the steppe
polecat anyway, so if it happened once, it could happen twice.  At the very
beginning of the development of the domesticated ferret, there must have
been alot of inbreeding to maintain the albino state.  All interbreeding
proves is a close phylogenetic relationship; similar but not necessarily
equal.  In short, there is no unrefutable evidence that the ferret is a
domesticated European polecat.
 
Evidence that proves the ferrets are difference species include increased
number of liters producable per year, different skull morphology, changes in
behavior, physiology, senses, inteligence, temperment, etc.  It should be
noted that many of these differences could be the rest of the domestication
process, which is in effect, a speciation process.  (Which means, even if
they started the same, they are now different.  Cool.)
 
In truth, neither side is compelling.  What is need is what is missing;
paleontological and/or archaeological evidence.  And with the American
public support towards scientific research, and the problem being one of
zoology and anthropology rather than pizza cheese-food, cosmetics, or breast
augmentation devices, I wouldn't hold my breath for funds to be made
available to solve the problem.  Even if funds were available, such as by
ending the tens of millions of dollars given away in tobaccoo subsidies, it
could take decades to find the answer.
 
I have made some very discrete inquiries in obtaining faunal remains from
Old World sites in an effort to look into the problem, and have had some
success (one of the reasons I am going to Europe--at my own expense--next
January).  I have been promised some bones from the Roman era, and some from
about 1000 BC, but basically I'm working for free (for them) in order to
find a few pieces of data (for me).  And lab work (with or without pay) can
be about as exciting as watching water evaporate off a plate.  So if there
are any really rich FML ladies out there who needs an aging long haired
boy-toy in exchange for funding this type of research, I'm available.
Otherwise, it will take a while.  (In the meantime, I buy lottery tickets,
because my chance of funding via gambling is higher than getting anything
from a Republican congress who are four months into this year's budget
without actually having one.  Am I the only one who noticed a failure to
remember history when Dole blamed Clinton for budget problems, when
republican presidents have been in control for 20 out of 24 years, and Dole
was in Washington voting yes?  BTW, in case you think I'm anti-republican, I
call Clinton the "Amazing Two-headed President." I would say to use
politicans for medical research, but then the law protects those with mental
handicaps, and I could be jailed for cruelty to subhumans.) In any case,
discovering the actual ancestor of the ferret is, at present, sometime away.
(Its premature to release details, but I am finishing a paper that addresses
why the discovery of ferrets in archaeological contexts would be quite
important.  If presented or published, it might spur more research.)
 
In short, and back to the point (sorry), flip a coin.  Heads, its Mustela
furo.  Tails, its Mustela putorius furo. But using the ability to breed as
a major criterion to define species is sophomoric science; the real
question is far more involved (Yes, I'm talking to you, you CA F&G morons)
 
Bob and the 13 Sprite Lovers
[Posted in FML issue 1530]