Hygenic behavior as recessive trait in bees

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Hygienic behavior is controlled by two recessive genes. One gene allows the worker to detect and uncap a cell that contains diseased brood. The other gene makes the workers remove the brood and discard it. It’s possible for a hive to contain one of these genes and not the other, in which case the hive won’t be hygienic. It’s also possible for different individual bees to have one, but not the other gene.