THE PHYLA ARTHROPODA AND ONYCHOPHORA 



Fig. 15.36. Hymenoptera: the honeybee, Apis mellijera. A, comparative aspects of the three 

 castes of a honeybee colony, fi, a worker honeybee visiting a flower; note the bulging pollen 

 baskets on the metathoracic legs of the insect, packed with pollen to be carried to the hive. 

 These pollen baskets, along with other special modifications, are found only in the worker caste. 

 {A, redrawn from K. von Frisch, 1953, Bwlogie, vol. 2, printed by permi.ssion of Bayerischer 

 Schulbuch-Verlag; fi, photograph by Charles Walcott.) 



performed at the entrance of the hive by the returning forager; the dances are 

 soon joined and imitated by other workers. A so-called "round dance" is per- 

 formed when the food is near the hive, and the abundance of the supply is 

 indicated by the vigor of the dance. For sources many hundreds of yards, 

 or even a mile or more, from the hive, the forager performs a more com- 

 plicated "waggle dance" involving a straight passage which indicates the 

 compass direction to be flown in seeking the food. By imitating the straight 

 part of the dance, other workers evidently perceive the pattern of polarization 

 of light from the sky, which is characteristic of the compass heading they must 

 fly. Analysis and integration of polarized light are presumably functions of 

 the well-developed compound eyes of these insects. Fantastic as these state- 

 ments may seem, they are all based on sound experimental evidence gathered 



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