Does anyone know whether someone has tried to breed bees selecting for
larger size?  It seems to me that there might be numerous advantages this
would confer:
the bees could carry larger nectar and pollen and water loads;  they might
be able to "buzz" pollinate blueberry blossom (maybe cranberry too, I don't
know if bumblebees do that in cranberry);  they might be able to fly at
lower temperature since their surface to volume ratio would decrease;  and
they might even be more prone to chewing up varroa mites as their larger
distant relatives the bumblebees apparently do.
 
In cows and pigs size is a characteristic that responds very quickly to
selection.  If I were going to breed for a larger bee, I would increase cell
size in foundation slightly and see if any hives responded to this challenge
{not such a big increase as to make them build drone comb).  It would be
interesting to see if the bees would increase their cell size instinct as
their body size increased. I think that the bees probably measure cell size
and bee space size in relation to their body,  much as the queen uses her
mandibles as calipers, but that is not necessarily the case.  Perhaps size
and measurement are of such fundamental importance to bees that breeding a
larger bee would be extremely difficult.
 
I would be most interested in information on this.
 
Have a  nice day.    Stan