adony melathopoulos said:
> I am of the... opinion... if varroa were introduced to a population
> of European honey bees the two species would evolve towards
> a more benign relationship.
> Strong support for this argument is that the closest relative of
> A. mellifera, A. cerana, has had a much longer relationship with
> varroa (V. destructor) and the relationship is far less damaging to
> the host than it is in A. mellifera.
I wish it were as simple as the proponents of this view hope,
but I must disagree.
These are different bees, and very different mites.
Apis cerana is able to tolerate Varroa JACOBSONI, while Apis
mellifera is plagued with the much more destructive Varroa
DESTRUCTOR. (They named it "destructor" for a good reason!)
While both situations can be described as "bees and mites",
the similarity ends there.
The fact that Apis Cerana colonies can tolerate the presence
of Varroa jacobsoni does not imply anything about the ability
of Apis mellifera to survive Varroa destructor. These are two
different bees, and two very different mites. The mites are
much more dissimilar than the bees are.
To make such a leap of faith would be similar to seeing a
group of 3-year old porpoises drive off a nurse shark in a
Cousteau documentary, and then tossing one's children
into the waters of Australia's Great Barrier Reef with
instructions to do the same if encountering a great white
shark. Both are cases of "mammals" and "sharks", so the
comparison is just as inaccurate as the comparison
between the two sets of "bees" and "mites" at issue.
Here's just one of many reference documents available on
the web that can help clarify a few of the many differences
between the two mites:
http://ethesis.helsinki.fi/julkaisut/maa/selai/vk/fakhimzadeh/detectio.pdf
Which says, in part:
"Varroa destructor Anderson & Trueman is an external parasitic
mite of honey bees. Varroa jacobsoni Oudemans was found on
Apis cerana Fabricius, in Java (Oudemans 1904) and until recently
was generally believed to be the same specie as V. destructor
(Anderson & Trueman 2000). Even though Varroa from different
population are physically alike, their virulence toward A. mellifera
is not uniform (Camazine 1986; Ritter et al. 1990; Moretto et al.
1991; Anderson 1994; Eguaras et al. 1995; De Jong & Soares 1997).
According to Anderson & Fuchs (1998) the mite that was described in
1904 as V. jacobsoni is still restricted to the Asian honey bee, A. cerana
as a host. Only two of the 18 different haplotypes concealed within the
complex of mites infesting A. cerana have switched host and have become
pest of A. mellifera worldwide. Both belong to V. destructor, and they are
not V. jacobsoni (Anderson & Trueman 2000; Anderson 2000).
These species differ significantly in size, reproductive characteristics
(Anderson 1994) and mitochondrial DNA (mtDNA) cytochrome oxydase I
(CO- I) gene sequences (Hunt & Anderson 1999; Anderson & Trueman
2000; Anderson 2000). According to Anderson & Trueman (2000) V.
destructor is larger than V. jacobsoni. Apparently, only V. destructor is
capable of causing extensive damage to bee colonies (Hunt & Anderson
1999)."
Much of the confusion between the two mites was because varroa mites
were not as well-documented as bees, and at first, the text-only description
of Varroa jacobsoni from 1904 (no photomicrographs in 1904) seemed a
good "match" for the mite found.
It was not until "mug shots" were matched up that the authorities realized
that they had accused, tried, and convicted the wrong mite.
Here are the mug shots, showing the gross physical characteristics of
the two types of mites, which are clearly different enough to see, once
one has side-by-side photos.
http://www.anu.edu.au/BoZo/trueman/labsite/successes.htm
One is a mere minor pest. The other is a hemoglyph-sucking,
virus carrying, mass murderer of the sort that prompts one to
ask Sigourney Weaver for advice. Why ask her? She has
significant experience with things like varroa. Look here:
http://hosted.avpnetwork.com/aliendomain/alien26.jpg
jim
farmageddon
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