PHYSIOLOGY AND BEHAVIOR OF THE ARTHROPODA 347 



diers and honey-ants (Fig. 17.19), appear. Trophallaxis is again the 

 prime integrating force of the colony. As in the termites, great numbers 

 of winged reproductives are produced seasonally by some unknown 

 mechanism. 



Honeybees. The queen honeybee is unable to found a colony or to 

 survive at all without workers. She appears in an established colony, 

 flies out of the hive with males in chase on the nuptial flight, is fer- 

 tilized, and then returns to the hive to begin producing eggs. Most of 

 the eggs develop into workers, and as in the other societies the integrat- 

 ing mechanism assuring that all members will be fed is trophallaxis. 

 Although there is only one caste of sterile female bees, these workers 

 are ditterentiated by age into three physiologically different groups as 

 described in section 319. If all the individuals of one of these age groups 

 are removed from the colony, the time scale of development in the 

 others is altered, and sometimes a given group will revert to a younger 

 stage. This suggests that trophallaxis not only assures feeding and de- 

 velops a hive odor but by the distribution of hormonal substances it 

 keeps the colony structure balanced. 



W^hen the colony becomes large the nurse bees set aside a few eggs 

 to be raised as queens. Adjacent cell walls are torn out to make larger 

 chambers, and there these few larvae are fed exclusively on royal jelly 

 for the whole six days of their larval life. When they pupate, the colony 

 begins to split up. About half of the workers induce the old queen to 

 leave, and they fly off with her to begin a new colony. The other half 

 remains. W'hen the first new queen emerges from her cell, she may also 

 be induced to leave with another group of workers if the colony has 

 become very large. Either she or the next queen, however, remains as 

 the new resident queen. As soon as one or the other is established the 

 few other queens that may be hatching are destroyed. 



It had been thought that the determining factor in queen produc- 

 tion was nutritional, but recent work suggests that the royal jelly con- 

 tains a hormone; if a larva receives enough of this it will mature as a 

 queen. 



Sex is determined by the usual chromosomal mechanism (p. 660) 

 in the termites, half of which are male and half female in all of the 

 castes. Most ants and bees, however, are female. Males are produced 

 only from unfertilized eggs and are haploid. They appear only with the 

 female reproductives in the ant colony, as part of the seasonal swarming. 

 Male bees are produced sporadically. They hang around the hive as 

 drones, doing no work and feeding themselves when hungry. Their 

 only function is to be there when new queens emerge. They chase after 

 her on the nuptial flight, and high in the air one of them mates with 

 her. In the fall, as the colony prepares for winter they are expelled from 

 the hive. 



156. Bee Language 



Bees have an additional social mechanism that greatly increases the 

 efficiency of the colony, an elaborate and remarkable language. Bee 



