A new study has revealed the reason behind honeybee queens' extraordinary promiscuity, by showing that the creatures have sex with harems of males to give birth to much better dancers. Bees are known to communicate the location of food by dancing, and it is this requirement that makes bee queens mate with several males, according to scientists at the Cornell University in Ithaca, N.Y.
Lead researcher Heather Mattila, a honeybee behaviourist at Cornell, said that the better the honeybees dance, the better they are at hustling for food.
Taking lots of male consorts is an unsafe proposition for bee queens, as it puts them at a greater risk of catching sexually transmitted diseases.
Furthermore, having several fathers could make a queen's children genetically different from each other, which in theory could threaten how well they all get along.
Still, honeybees continue practicing polyandry, with some North American honeybee queens each having sex with an average of seven to 20 males, and the giant honeybee in Asia know to demand up to 104 mates.
To understand the mechanism behind honeybee queens' promiscuous life, the research team compared a trio of queens each inseminated by just one male drone with a trio of queens inseminated by 15 drones.
They found that the genetically diverse colonies of queens inseminated by 15 males turned out better dancers, performing more waggle dances and longer dances.
Worker bees use waggle dances to reveal where food is to nest mates, and genetically diverse colonies dispatched more foragers to look for food.
"What really surprised us was the extent of difference. In some colonies, you can see the less genetically diverse bees pretty much just standing still on the honeycombs on the videotape, while bees in the genetically diverse colonies are dancing or have left to go forage," LiveScience quoted Mattila, as saying.
She also suspects that some males could result in better dancing progeny than others.
"Honeybees may look all the same, but they're not — some bees are better at some tasks than others. So queens might mate with a lot of males to increase the likelihood of getting a drone that fathers good dancers, or produce workers want to follow good dances," she said.
The scientists said that better dancing is not the only advantage of genetic diversity for honeybees. Research has shown that it boosts a colony's resistance against disease.
"It could be that genetic diversity is vital for getting enough food to feed huge, energetically demanding colonies," Mattila said.
"Honeybees are unusual in that they tend to have massive populations and complex ways of communicating between nest mates, and it could be that once you reach a certain level of complexity, genetic diversity helps provide the productivity that is needed," she added.
The findings are published in the Proceedings of the Royal Society B.