> While on the subject of varroa reproduction, can someone offer an explanation of how varroa maintain genetic health while constantly inbreeding? 

A more interesting question is how they can develop genetic diversity with so little outcrossing. We often hear them referred to as "virtual clones." It turns out that even truly clonal species have significant genetic variation. Clonal species:

> like all other living organisms, are not immune from the effects of mutation, selection/genetic drift, adaptation, and extinction. With this in mind, it is thus strange that the members of such a lineage are still assumed by some scientists to be “genetically identical” to their stem mother, and thereby, with little genetic/functional plasticity to be able to adapt in the face of changing ecological circumstances.

> the various DNA molecular marker studies performed on aphids display widespread genetic variation within and between different clonal lineages, as expected since mutation is a fundamental property of the DNA and hence the genome itself.

> The large majority of these mutations are likely to be mildly deleterious and at non-coding regions of the genome; however, others are probably important, that is to say, at coding regions and are thus positively or negatively selected for. In the case of the Spotted Alfalfa aphid, some mutations were shown to confer resistance to organo-phosphates insecticides, so that the insect became resistant to these pesticides within a relatively short time after its introduction into the USA in the early 1950s

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html