150 evolution: the ages and tomorrow 



works within wide variations of outside temperature. In 

 spring, for the better development of the grubs, bees keep 

 the hive at blood heat, 95 degrees. On hot days certain bees 

 take over the task of creating a current of air through the 

 hive; this they do by standing at the door and beating vigor- 

 ously with their wings. 



There have been many books and short articles published 

 from time to time on the honeybee; but undoubtedly the 

 great classic of our time on the behavior of an insect is Bees, 

 Their Vision, Chemical Senses, and Language, by Karl von 

 Frisch. With great patience and lifelong perseverance this 

 Bavarian zoologist has given us many new facts about bees 

 and has corrected many old errors. Von Frisch's method 

 has been to mark the individual bees with dabs of bright 

 paint on various parts of the body, and then to follow their 

 individual activity from the "cradle to the grave." In this 

 way and using specially built glass hives, von Frisch has 

 observed intimately the life and behavior of the bee. 



In a single colony, where there may be 30,000 workers, 

 the division of labor is not rigidly apportioned among in- 

 dividuals whose lifetime is spent doing a single job, as in 

 ants. On the contrary, there is a succession of jobs which a 

 single individual performs, one after the other, as it grows 

 older. Queens carry on reproductive activity exclusively 

 throughout a rather long Hfe (upwards of five years), but 

 the workers have instincts for doing a variety of different 

 jobs as they grow up. Beyond their possible duty of fertiliz- 

 ing a queen, males (the drones) are superfluous and do 

 nothing, being killed or dying of starvation in the fall of 

 each season. The sterile workers (females) live about fiYQ 

 weeks as actively winged adults. Their whole life cycle 

 includes three days as an tgg, six days as a growing grub, 

 twelve days as a resting pupa, and about five weeks as a 

 winged adult. 



In this short but incredibly active adult life there are, in 

 turn, three main periods. During the first ten days the bee 



