Q:"Which name is right, _Mustela_furo_ or _Mustela_putorius_furo_?" and "I
understand mink and ferrets successfully mate? Have you ever seen this?"
A: Yes, go to www.mustelidsex.com/fertxxxmink.....
Yes they can, but not in the way you think. A few scientists have stated
they were able to fertilize eggs from one with sperm from the other, but
I can find little evidence that the embryos survived, nor of the events
occuring in nature.
There are actually many sources that discuss the successful hybridization of
mink and European polecats (and if a polecat can do it, so can a ferret).
However, they are not discussing interspecies reproduction with the American
mink, but instead with the European mink. Most of the confusion results
from people using the term "mink" rather than the longer popular name or the
scientific name. European mink (_Mustela_lutreola_) are quite different
from American mink (_Mustela_vison_), and their very close external
resemblance is due to something called convergent evolution. Both species
live in similar environments, are about the same size, and eat about the
same things so they look the same (American mink are more generalist
feeders). A similar thing has occurred between the Mustelidae and the
Viverridae, which is why some mongeese look so similar to weasels and
polecats.
But there are some real differences. In one recent paper, it was suggested
the Genus _Mustela_ is bimodal, with one group being more polecat-like and
the other more weasel-like. The "polecat" mode had more chromosomes and
were more mtDNA related than the "weasel" mode. In this scheme, American
mink would be considered to be in the "weasel" group, and the European mink
would reside within the "polecat" group.
This idea is supported by a close look at mustelid chromosomes. The
American mink has only 30 chromosomes. The steppe polecat has 38
chromosomes, as does the black-footed ferret and the European mink. The
European polecat has 40 chromosomes, as does the domesticated ferret,
although at least two sources indicate some domesticated ferrets have a
variable number of chromosomes, ranging from 38 to 40. The closeless of
this mode is evidenced by the existence of fertile hybrids between them
(steppe x bbf; steppe x E. polecat; E. polecat x ferret; E. polecat x E.
mink). Based on this pattern, it is likely all the "polecat mode" members
can successfully interbreed, and chromosome number is not very important
for successful breeding.
In conventional evolutionary theory, species with larger numbers of
chromosomes are usually derived from species with fewer chromosomes. Thus,
it is likely that the European polecat is derived from either the steppe
polecat or a common ancestor. This is the sticky point about the ancestry
of the domesticated ferret; who was it's ancestor? Having 40 chromosomes
that have a similar appearance to those of the European polecat has long
been cited as proof of ancestry, but clearly, the mutation which resulted in
the polecat's 40 chromosomes could have occured during the domestication of
the ferret, and it could have just as likely been derived from the steppe
polecat, or even both polecats. Without a detailed examination of the
genetic structure of the "polecats," determination of ancestry is
conjectural only.
This discussion raises two very important points in domesticated ferret
issues. First, the use of _Mustela_putorius_furo_ is questioned until
evidence of a more defining nature is found, and Mustela furo should be
used instead. This point is further supported by the continued use of
_Canis_familiaris_ for the dog, even though DNA testing has firmly
established it was derived from the wolf, _Canis_lupus_. The International
committee on taxonomic nomenclature is currently hashing out (or at least
discussing it in their journal) the problems of naming domesticated animals.
Until then, stay with _Mustela_furo_.
The second point is that the close ties between the polecats and the
European mink support the idea that it is unlikely ferrets could establish
feral populations in the United States. In a recent paper, it was shown
that American mink were able to completely establish themselves throughout
Europe within a human lifetime, mostly since World War Two. It only took
20-40 years for American mink to populate some entire countries. These
animals came from fur farms, and where either accidentally or deliberately
introduced. American mink compete against both the European mink and
polecat and in some manner is more fit than either of the two. In North
America, ferret farms have been in existence far longer than any American
mink farm in Europe, and ferrets have been actively bred for the research
and pet trade since the early 70s, yet not a single self-supporting feral
colony exists anywhere in North America.
If you take two different species and release members of each into the
opposite species's territory, and one takes over while the other doesn't,
what does that tell you? It would tell most intelligent people the likehold
of the less fit species taking over territory from the more fit species as
rather slim, if possible at all. I guess my point that the CaCa Fish and
Gestapo is not intelligent is well taken.
This is but two drops in a sea of substandard, yet completely idiotic "I'm
stupid and I'm not afraid to use it" decisions by the putrid and bloated
corpse of wildlife mismanagement, the CaCa Fishing Gestapo. Unlike the
truely unintelligent, where genetics or environmental forces have unfairly
lowered a person's mental abilities, Fishing Gestapo agents have CHOSEN
intellectual retardation. These soulless spawn of wretched perversions,
lacking identifiable earthly parentage, have proven time and again education
doesn't matter so long as you have a gun and know how to stalk the wild
suburban housewife. California needs to flush.
Bob C and 20 MO Poledogs of Denigration
[Posted in FML issue 2358]
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