Jim Fischer said:  “Whatever level of "sterile" we choose, we should see 
some specific 
negative impact fairly quickly if microorganisms are mission-critical
to the health and well-being of bee colonies.”

     OK so it would not be impossible.  Would you think it necessary to 
follow said colony through at least one complete generation starting with 
your original brood and having them age completely to the field bee stage 
while raising new brood which the queen has laid?  I am hypothesizing 
(speculating) that a truly symbiotic microorganism might depend on 
behavioral factors involved in brood rearing, or even egg laying, in order 
to serve its intended purpose.  Perhaps the exchange of fluids between 
field bees and house bees might serve as a critical link.  So then if the 
capped brood that you started with did not die before reaching field bee 
stage, it would not prove that microorganisms were not needed.  They might 
play a critical role at a later stage in the cycle.  It could also be that 
a prolonged absence of such beneficial organisms might gradually wear a 
colony down requiring more than one generation to finally do it in.   The 
complexities of such relationships can be mind boggling.  Never mind trying 
to figure out which of the thousands of micro organisms or combinations of 
them is actually vital or beneficial.  For that you would have to be able 
to eliminate them one by one or eliminate all but one at a time.
    Other than the missing microorganisms, I’m trying to think of any other 
factor, the absence or presence of which could result in the death of such 
a very small colony in such an environment; a colony that certainly 
wouldn’t be expected to survive under normal field conditions.  I can’t 
think of any.  Can you?  Then in the absence of any other factor, unforseen 
or otherwise, if the colony died right away you could say with a high 
degree of confidence that it was the lack of some beneficial microorganism 
that did them in.
     My whole point, I guess, is that proving that microorganisms are not 
beneficial or vital to the well being of honey bees would be at least as 
difficult as proving that they are.  In any case it hasn’t apparently been 
done.  There is an abundance of such relationships in nature, though, so 
assuming that one or more of them exists in honeybees is certainly not far 
fetched.

Steve Noble            

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