A pathogen, however mighty, clever, and enduring, cannot and must not and
should not and will not wipe out its host completely, a self-defeating,
self-anihilating process because its own survival depends on the very
viability of its host.  What is it going to eat when all the bees are
gone?  A cod?  (They are pretty much gone, too)
Just as in beekeeping, following nature, the pathogen must strike a
sembiotic relationship with bees, never one side dominating the other;

I am glad to see that so many people on this list believe in
evolution, but there are a few aspects of evolution that seem to be
overlooked in these discussions. One, evolution cannot move toward a
goal. Nature does not have capacity to see into the future and create
improved life forms in this manner. Certainly, something as simple as
a mite has no ability to regulate itself in order to prevent the
killing of the host. Over time, however, mites may be *selected* which
do not kill the host. This is not a given, however. Plenty of
parasites kill their hosts and perish with them.

The point being: while varroa mites kill individual colonies, they
obviously cannot kill off the species, as there are strains of honey
bees that can coexist with the mites. The mites will not wipe out the
whole honey bee population (fulfilling the famous Einstein prophecy).
It could be that only tropical bees like Africans and Asians
adequately hold down the mite populations. It is conceivable that
Northern areas will have to continually restock their hives with bees
from the South, but that's nothing new.

* * *
A parasitoid is an organism that spends a significant portion of its
life history attached to or within a single host organism which *it
ultimately kills* in the process. Thus they are similar to typical
parasites except in the certain fate of the host. In a typical
parasitic relationship, the parasite and host live side by side
without lethal damage to the host.

Typically, the parasite takes enough nutrients to thrive without
preventing the host from reproducing. In a parasitoid relationship,
the host is killed, normally before it can produce offspring.

This type of relationship seems to occur only in organisms that have
fast reproduction rates (such as insects or mites). Most biologists
use the term parasitoids to refer only to insects with this type of
life history, but some argue the term should be used more embrasively
to include parasitic nematodes, seed weevils, and certain bacteria and
viruses all of which obligately destroy their host.

-- 
Peter L. Borst
Danby, NY  USA
42.35, -76.50

picasaweb.google.com/peterlborst

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