Re: varroa destructor introduction and evolution

> As well, the article said that the mother varroa enters the brood cell
> and lays one male and upto 5 females.  The male then mates with his
> sisters.  Isn't this inbreeding of the most intense kind?  Why haven't
> they inbred themselves into dysfunctionality and unsurvivability by
> now?

you are right, but nature has found a way to take advantages of 
inbreeding, as that set of remaining alleles stabilizes the suitable 
features of the offspring - think of parthenogenesy and even paedogenesy

a reduced chance of genetic distribution can happen at those heavily 
infested bee swarms where more than one mother mite enters a cell

the complete change from varroa jacobsonii to v. destructor seems to be 
one of the consequences of the beekeeper's method to cut out infested 
drone combs, so that mites preferring worker brood were able to attain 
majority

cheers kauhl