Deknow wrote:
>if all the mites in the colony (and/or apiary) were genetically identical, 
>then how would this resistance to apistan arise?

According to Martin: The resistance mechanism is believed to come from a 
change in the sodium channel (do not ask me to explain it!), which is a 
change which has no cost to the mite.  He believes that this change occured 
in a single mite, probably in Sicily, and has spread from there i.e. all the 
resistant mites are clones of that one mite.  He says that the movement of 
resistant mites is followig the same path as the original spread.

Best wishes

Peter Edwards
[log in to unmask]
www.stratford-upon-avon.freeserve.co.uk/

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