Peter, thanks for explaining the suicide theory further.   I guess I 
can see how a generalized behavioral response such as self sacrifice could 
be of benefit in certain conditions and in other conditions might be 
counter productive, as would seem to be the case if it were to result in 
the collapse of the colony.  You would have to assume that if such a 
mechanism does exist it would have to have been the result of evolution 
over long periods of time in response to stresses that have also existed 
for long periods of time.  If suddenly a new wrinkle were to come into the 
picture in the form of a particularly pernicious pathogen that had not been 
encountered in the past, then this behavior might not work the way it was 
designed to.  What this tells me is that it might be quite tricky, to say 
the least, to select for this behavior as a way of combating something like 
CCD.

Bill Truesdell wrote:  
“look no further than Tracheal mites in winter. Infected bees 
will move out of the hive and cluster on the hive and die of the cold.

    Bill, I have actually seen this myself in one of my hives last spring.  
I concluded, as you say, that it was tracheal mites.  A lot of bees were 
dying after coming back from the field and congregating near the entrance.  
There was no streaking.  The bees looked like they were breathing hard.  I 
hit the hive with a Formic acid treatment and the hive, which I had pretty 
much given up on, recovered amazingly.  It actually produced a surplus.
It would have been interesting to see if the colony would have recovered 
without the formic treatment.  If so, then it would seem to be a case in 
support of the suicide hypothesis.  But then there would have to also be no 
other logical explanation other than deliberate self sacrifice, such as… 
that they instinctively new it would be harder to breath in the hive than 
out in the open and could not foresee that they would die outside.  Either 
way if it resulted in a net benefit for the colony and resulted in the 
colony surviving, that behavior would tend to be passed on. 

Steve Noble  

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