A reputation for chastity may have worked for Elizabeth I of England, but queen bees who start their reign with a royal orgy end up with healthier hives.
When queens mate with multiple males their hives end up with greater genetic diversity and more robust communities of symbiotic bacteria living in the bee’s guts. Heather Mattila, an ecologist at Wellesley College, found significantly more gut bacteria in bees from hives where the queens partnered with multiple males than in more sexually deprived hives.
“We’ve never known how healthier bees are generated by genetic diversity, but this study provides strong clues,” said Mattila in a press release. “Our findings suggest that genetically diverse honey bees have the advantage of broader microbial communities, which may be key to improving colony health and nutrition — and to understanding factors that can mitigate honey bee decline.”
Plentiful gut bacteria allow the bees to break down food more easily by helping turn pollen into “bee bread,” the food of the worker masses. Just as yeast makes flour into bread for humans, a variety of organisms make pollen more palatable as bee bread.
Mattila and Irene Newton, a microbiologist at Indiana University, tested the effects of multiple mates on genetic diversity and bacteria by developing 22 experimentally controlled colonies of honey bees, Apis mellifera, divided into two categories. Twelve benefited from a queen inseminated with a mix of 15 male bee’s sperm. The other 10 had a chaste queen with only one mate.
Queen honey bees only mate once in their lives. In nature this happens when a plethora of drones fly up in a mating dance with the queen. But, in an example of nature’s extreme sado-masochism, the male’s reproductive organ is torn off as he mates with the new queen. Later males remove their fallen comrade’s phallus and mate with the queen, losing their phallus in the process as well. The stored sperm from multiple partners is used to produce hundreds of offspring from that one wild day.
So, in the experiment, the initial artificial insemination was enough to last Queeny a lifetime.
The polyandrous, multi-male queens’ hives hosted 1,105 species of microbes with 40 percent more beneficial bacteria than the other group. The monogamous queens’ hives had only 781, as well as 127 percent more potential pathogens.
The results of the study were published in PloS ONE.
Understanding bee health could help entomologists save honey bees. Bee numbers have been declining by at least 30 percent every year, according to the US Department of Agriculture due to the mysterious Colony Collapse Disorder.
“There is a large community of bee researchers in the United States and around the world, and we are doing everything we can to maximize the health of our most important pollinator,” said Mattila.
IMAGE: A European honey bee (Apis mellifera) extracts nectar from an Aster flower using its proboscis. (John Severns, Wikimedia Commons)