Because queens mate early in their lives and store semen, it stands to reason that queens that have mated multiple times and accumulate more semen might be more valuable to a colony. But Tarpy said researchers have not studied the impact of the number of times a queen mates on her physiology until now.
To determine the effect mating has on honey bee queens, the scientists artificially inseminated queens. Its difficult to determine the number of times a queen mates under natural conditions. Some queens were inseminated with the semen from one drone, others with the semen from 10 drones. The scientists then put the queens in hives and observed them.
They found that worker bees paid more attention to the multiply inseminated queens. Worker bees demonstrate what is known as a retinue response to their queen; they lick her and rub their antennae on her. The retinue response to the multiply inseminated queens was more pronounced.
This tells us the workers can tell how many drones the queen has mated with, said Grozinger.
Like many animals, honey bees use pheromones to communicate. When Richard analyzed pheromone produced in the mandibular gland of honey bee queens, she found that pheromone composition changes dramatically after queens mate and that the number of times the queen mates appears to be a key factor in determining the extent of pheromone alteration.
Richard added that when worker bees were exposed to pheromone from queens inseminated with semen from one drone and queens inseminated with semen from multiple drones, the workers showed a preference for the pheromone from the multiply inseminated queens.
Richard added that an analysis of the mandibular gland pheromone found differences in the chemical profile of pheromone from once-inseminated and multiply inseminated queens
|Contact: Dr. Freddie-Jeanne Richard|
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