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Keith Delaplane is Professor of Entomology at the University of Georgia in Athens. He has a family history of beekeeping; he received his first hive at 13, and his grandfather was a beekeeper in Indiana. He studied for his MSc at Purdue in 1983, and moved to Louisiana to complete a Masters and PhD in 1989 before taking up the post at LSU. In 2014 he was recognised by the Queen with an honorary MBE. Delaplane has worked on and off in Britain since 2000 for the Natural Environment Research Council. Over the past 14 years, he has given support to local and national beekeeping associations throughout the UK where he is well known. He was instrumental in the formation of the Institute for Northern Ireland Beekeepers, and in 2012 and 2013 he was visiting sabbatical scientist at the U.K.'s National Bee Unit where, with others, he researched honeybee pollination, health and breeding. When he's not working, Tolkien, CS Lewis and Harry Potter, and an interest in medieval and Christian history keep him busy. His latest study appeared in my Inbox this morning. It contradicts some earlier work and places a much higher value on multiple mating (polyandry), dealing with a concern I have about selecting for VSH, among other things. I talked about some of that in this post; [URL="http://www.nzbees.net/threads/letter-the-nuptial-flight.1767/"]Letter: The Nuptial Flight[/URL] , which will also give some of you a 'backgrounder' if you haven't the faintest idea what this is all about. [B]Abstract[/B] [I]A honey bee queen mates on wing with an average of 12 males and stores their sperm to produce progeny of mixed paternity. The degree of a queen’s polyandry is positively associated with measures of her colony’s fitness, and observed distributions of mating number are evolutionary optima balancing risks of mating flights against benefits to the colony. Effective mating numbers as high as 40 have been documented, begging the question of the upper bounds of this behavior that can be expected to confer colony benefit. In this study we used instrumental insemination to create three classes of queens with exaggerated range of polyandry – 15, 30, or 60 drones. Colonies headed by queens inseminated with 30 or 60 drones produced more brood per bee and had a lower proportion of samples positive for Varroa destructor mites than colonies whose queens were inseminated with 15 drones, suggesting benefits of polyandry at rates higher than those normally obtaining in nature. Our results are consistent with two hypotheses that posit conditions that reward such high expressions of polyandry: (1) a queen may mate with many males in order to promote beneficial non-additive genetic interactions among subfamilies, and (2) a queen may mate with many males in order to capture a large number of rare alleles that regulate resistance to pathogens and parasites in a breeding population. Our results are unique for identifying the highest levels of polyandry yet detected that confer colony-level benefit and for showing a benefit of polyandry in particular toward the parasitic mite V. destructor.[/I] [B]Delaplane KS, Pietravalle S, Brown MA, Budge GE (2015) Honey Bee Colonies Headed by Hyperpolyandrous Queens Have Improved Brood Rearing Efficiency and Lower Infestation Rates of Parasitic Varroa Mites. PLoS ONE 10(12) doi:10.1371/journal.pone.0142985[/B]