Pheromone the Key to Queen Bees' Reign
By Mick Kulikowski, News Services
There's a good reason people use the term "queen bee" to refer to a domineering female.
After all, say NC State bee researchers Dr. Christina Grozinger and Dr. David Tarpy, queen bees have control of much of what happens in the hive. The queen's daughters - the hive's worker bees - take care of the nuts and bolts of life in the hive while the queen goes about the business of increasing the brood.
Most of the time, that is.
Grozinger says that there are occasions when workers are less attentive to the queen's wishes. They occur when the queen's primary signaling mechanism - queen pheromone, which attracts workers to the queen and inhibits worker bee ovary development to prevent workers from laying eggs - somehow loses effectiveness.
So-called "anarchist" workers will sometimes activate their ovaries and produce unfertilized male bees in the hopes the males will fly away and mate, spreading their genes here and there.
Other times, specifically when a queen has mated just one time - queens normally take one or two mating flights and mate with an average of 12 and up to 40 males - workers will try to overthrow the queen.
"Workers can sense from the queen pheromone when the queen is getting old or is not well mated," Grozinger says. "We're studying what happens to the chemistry and physiology of mated queens and how the pheromone affects workers."
In either case, Tarpy says, workers are doing what they think is best for the survival of the colony.
"Workers want the best queen possible and will oust the queen if they sense she's not up to snuff," he says.
Examining which genes are turned on and off during these times of reticence and rebellion is part of Grozinger and Tarpy's research program.
The results could be important to human reproductive health, the scientists say.
"Bees have retained genes similar to human genes that have been lost in other research models like Drosophila, the fruit fly," Grozinger says. "So in some ways they may be better models to study what genes do in humans."
The way queen mating affects relationships in the hive is, the researchers say, very important to colony survival, and, therefore, to agriculture. Healthy bees are needed to pollinate about 100 important crops responsible for $20 billion per year.