Bee genetics

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The other odd thing about bees is their habit of multiple mating. The queen is quite promiscuous and mates with from 10–20 drones, usually in 1 or 2 mating flights over the course of a couple days. The sperm is stored for years in an organ called the spermatheca. Actually the sperm from one drone is more than enough to fill the spermatheca. So apparently the queen goes out of her way and at great risk to mate with so many drones, just to gather up extra genetic diversity for her colony. This extra diversity is thought to help in providing genetic resistance to diseases. Also since bees tend to specialize in performing certain tasks in the hive, by having a larger diversity of fathers, the colony may perform more efficiently.