Saturday, August 15, 2009
Last week a member of Pacific Science Center’s Science Interpretation Department made an interesting observation at the bee hive, found in our Insect Village. She spotted a robust queen, efficiently laying eggs in the cells of the hive. Continuing to look around the rest of the hive, she made another observation that didn’t make quite so much sense. There was a second queen doing the exact same thing. (Dun-Da-Dun-Dun!)
Most people know that for a bee hive to live and thrive, it must have a queen. The queen is the largest bee in the colony and she is responsible for laying all of the eggs. Queen bees usually live between one and five years, while worker bees’ lives are measured in weeks, or at most months. Over time, the queen bee’s body will age and deteriorate, and eventually the time will come for her to be replaced. Beekeepers often replace the queen when they see signs of aging, but in the wild, replacement can happen in one of two ways:
Most often, an old queen dies suddenly before the rest of the colony has a chance to prepare. With no queen, what is a colony to do? Why, raise a new queen of course! Several larvae are selected at random and installed in larger cells built especially for them. These are generally found on the bottoms of the hive frames. Although genetically identical to a worker, the queens are physically different. They are fed large amounts of royal jelly, which allows their ovaries to mature. They will emerge as virgin queens. The first virgin queen to emerge will eliminate any others with a quick sting to each of the remaining queen cells. Then she takes off on a short mating flight before returning to the hive to settle down into her role of Queen Bee.
Alternatively, the colony will detect signs that the queen is starting to get old. As her pheromone output decreases and she fails to perform at the speed the workers want to see, the workers will begin to rear new queen cells. Once a new queen is available, the workers will surround the old queen so tightly that she overheats and dies. Ouch! The old queen has just been superseded.
We believe that in our hive, our old queen is being superseded. Although it is rare to catch the hive at a time when both the old queen and the new queen are alive and actively laying eggs, it is not entirely unheard of. While we have been able to locate one robust and healthy looking queen, the old, tired queen (distinguishable by a yellow dot painted on her thorax) has still been spotted hanging around the hive recently. How long will she remain? Stop by the bee hive on your next visit to Pacific Science Center and perhaps you can help us to solve this mystery. (Dun-Da-Dun-Dun-DA!)