The Sad Saga Of The Drone Bee
The plight of the male honey bee is one of the classic examples of sexual suicide. This incredible story is actually very complex and is eloquently explained by Mark Winston in his fascinating book The Biology of the Honey Bee (Harvard University Press, 1987). Honey bees are social insects that live in complex colonies. They have a division of labor with a true caste system in which different bees assume various roles within the colony. In fact, the way that all the thousands of individuals selflessly serve the collective is somewhat reminiscent of “The Borg” in Star Trek: The Next Generation. Compared with the smaller diploid female workers, the haploid drones have a relatively easy life–until that fateful day when they must fly into the sky for their rendezvous with a sexually receptive queen. The entire sex act takes place during flight, like a jet fighter refueling in mid air. Only in the case of honey bees, the actual bridge between the drone and the queen is his extended penis apparatus (endophallus) which is tightly plugged into the sting chamber of the receptive female. His explosive ejaculation ruptures his everted penis apparatus and propels semen into the queen’s oviduct. In addition to the forceful ejaculation of semen, the terminal bulb at the tip of the everted endophallus remains in the queens vagina, and according to Mark Winston (1987), this “plug” may function to prevent semen from flowing out of the vagina following copulation. [So there is truth in the old tale about the drone’s penis breaking off inside the female.] In the sci-fi film “Zzzzz” (a TV episode from the 1964 Outer Limits series), a queen bee metamorphosed into a women named Regina. In this “B” rated-film, Regina wanted to mate with the entomologist Ben Fields to produce a super race of bees. It is now very clear why the terrified entomologist/bee keeper did not want to have sex with this queen bee lady. Getting back to the world of real honey bees, the drone bee dies within minutes after his violent eruption of semen and literally falls from the sky.
With her sperm receptacle (called a spermatheca) filled, the queen can lay fertilized, diploid eggs (which become females) and unfertilized (haploid) eggs (which become males) in the hexagonal wax cells of her hive, in one of nature’s truly amazing insect cycles. In case you are wondering, worker bees build unfertilized hexagonal cells a little larger in order to accommodate the drone. When full, the queen’s spermatheca may contain more than five million sperm, more than enough to lay 1500 fertilized eggs daily during the summer, and up to 200,000 fertilized eggs annually during her life span of nearly four years. According to Mark Winston (1987), the queen may get a complete fill-up of sperm on one mating flight (often from more than one male), or she may make several flights over a period of several days to a week. And during the mating flight of one queen, up to 17 male drones may commit sexual suicide.
In a PBS TV broadcast about honey bees, the narrator referred to drone bees as “clones” of each other. Since clones are usually defined as genetically identical individuals (usually derived asexually), WAYNE’S WORD strongly disagrees with the accuracy of this broadcast. Although the haploid drone comes from an unfertilized egg with only one set of chromosomes, they are certainly not all genetically identical. The diploid queen bee undergoes normal meiosis (oögenesis) producing haploid eggs. During this cell division process her 16 pairs of homologous chromosomes become altered and reshuffled through crossing over and random assortment, resulting in haploid eggs that are not chromosomally identical. In fact, with 16 pairs of homologous chromosomes, there are 65,536 different chromosomal combinations possible. Furthermore, the additional random combination of gametes during fertilization also insures that worker bees are not chromosomally identical. One more gee whiz comment about honey bees. Since the foraging bees bring nectar back to the hive in special stomachs (where it is converted into honey and regurgitated into wax cells of their hive), honey is truly analogous to bee vomit.