Thanks for the research citations- now we're getting somewhere.
Based on the papers posted, is it safe to assume the line of thought we are trying to unpack is not whether Natural Selection is equipped to address a novel parasite like varroa, but whether Natural Selection is efficient at this purpose for our apicultural needs?
In the first paper cited 'Characteristics of honey bee colonies (Apis mellifera) in Sweden surviving Varroa destructor infestation' (https://hal.science/hal-01003560/file/hal-01003560.pdf), Locke and Fries conclude: 'Our results clearly demonstrate a significant reduction in the reproductive success of Varroa mites (measured as the ability to produce at least one viable offspring) in a European population of A. mellifera colonies where no mite control was practiced for more than 10 years. The surviving colonies had on average almost twice the proportion of infertile mites, more than twice the proportion of dead progeny, significantly reduced fecundity and an overall reproductive success rate of less than 50% compared with over 75% in control colonies. Delayed egg laying by the mother mites was proportionally the most frequent cause of reproductive failure with dead progeny as the second most common cause. Reduced fecundity, along with the reduced ability to produce viable female offspring clearly, is important to explain the lower mite infestation rates in the surviving population.'
In the second, 'Prospects, challenges and perspectives in harnessing natural selection to solve the ‘varroa problem’ of honey bees' (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10035043/), Guichard et al orient their research towards, '... strategies to improve the probability for a successful outcome in natural selection‐based programmes, also taking into account their distinct possible objectives. We have shown above that a nonnegligible degree of human intervention is required to assist the process and ensure the long‐term occurrence and effectiveness of selected traits under field‐realistic conditions at low costs and with minimal collateral damages. Thus, the proposed process involves a combination of natural and human‐directed selection processes.'
And in the third, 'Natural selection, selective breeding, and the evolution of resistance of honeybees (Apis mellifera) against Varroa' (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7236208/), van Alphen and Fernhout conclude, 'Natural and artificial selection at colony level can also be used in closed populations (e.g. on islands or otherwise isolated mating yards) providing that genetic variation in these populations is maintained. Resistant colonies produced in this way can then be used to increase the level of resistance in large panmictic populations. Once the resistance level has passed the threshold where it becomes profitable for apiculturists to stop chemical treatments of the mite, natural selection can proceed to make European and North American honeybees fully Varroa resistant.'
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