Hi All

> This is irrelevant in a clonal animal as the *two* mites will carry the
> same genes.

It really comes down to the population genetics of the mite.  It is possible that one clone spread into the area, and only one clone is still found there.  Often happens with a new wave of invasion of a colonising organisam.  It is also possible that the original population was mixed in the first place, or that variation came in during successive waves, not obvious to the beekeeper.

all the best

Gavin

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