Randy:

 Thus it wasn't so much that there were two "types" of bees kept, but
rather a
high-mite group and a low-mite group, and that mites drifted from the
high
mite colonies to the low-mite colonies at a greater rate than vice
versa,
as would be expected by diffusion.

Yes, it appears as if mites diffused, and yet if you look at the total
mite load in each apiary, somehow the two "comingled" apiaries (in sun
and shade) had much higher overall levels of mites, regardless of type.
 I see no biological reason why comingling of types would promote
higher overall mite loads.  Could it just be an apiary effect that was
incorrectly interpreted as an effect of co-mingling?  This could be a
clear example of the perils of pseudo-replication which inevitably
happens in most bee field experiments.  Subunits (colonies) are
replicated, but treatments (apiaries) are not.  The "correct" design to
make conclusions about drift and diffusion would require multiple
apiaries receiving each treatment.  Seldom done, but statisticians
continually point this out.   

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html