Bill,

>>1. it is an unnatural cell size for the bee if the reason is crowding

There are two more hypothesis:

1. A lower reproductive rate in the smaller cells.  One possible reason mites prefer drone cells is that there is perhaps more room and the mother mite can raise more mite offspring.

2. The larger pupae offer a greater food supply for the mites and result in more mite offspring.

>>...why does 5.0 not work if that is natural for a race?

If the health of the ferals I have seen is any evidence then just over 5.0 mm seems to be common size in the lower part of the brood combs in my area.

We are not out of the woods just yet and we may be headed in the right direction.

Waldemar

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