At 09:26 AM 2/21/02 -0700, you wrote:
>I don't see why the mites, most females of which will breed with a brother,
>would have that many more *different* sets of genes than honey bees, queens
>of which may breed with distant hives, except where mites from several
>diverse sources heavily infest a colony.  I assume that this latter case is
>not all that common except in a migratory situation where hives are moved to
>a common location, since mites are not able to fly except on a bee.  What am
>I missing?

The different sets may not vary by much.  In most sexual production the process
of production of the gametes ensures that most offspring are unique, and even
though brothers and sisters are very similar they vary to a small degree.  Each
individual and each generation represents a chance of that small difference
being
something significant (like resistance to camphorus).

This chance is significantly reduced in the honey bee (as compared to the
mites)
because the male is half diploid and contributes identical sperm (as
apposed to normal
cell division that results in non identical sperm),  and the number of new
reproducing
individuals created over a period of time is small, only a few new queens
every year.
Selective breeding does speed up the process by breeding many queens and
eliminating
all but the best, rather than natures few queens and eliminating only the
few weak.

Of course human intervention has had a significant impact on the natural
process.
The introduction of chemicals to control mites has forced selective
breeding on the mites
as well as allowing weak queens (hives) to survive mite infestation keeping
weak mite
susceptible genes available.  Breeding programs, SMR, natural treatments,
etc. will
or have a further effect on the gene pool, both for the bees and the
mites.  I believe, in
general, that only using chemical and IPM methods without a breeding
program will
eventually leave bees at a disadvantage simply because the mites have more
generations
and reproductive members vs. bees.  And anyone who does any sort of IPM or mite
treatment is selectively breeding mites (until someone finds a treatment
that kills
all mites), yet relatively few actively selectively breed bees (simply
raising bees from known
stock doesn't count).


-Tim