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EVOLUTION OF ANIMALS 



Part V 



/ 



XOiM'Y 



Fig. 30.26. Bees distinguish between solid and broken patterns. They do not 

 learn to distinguish between different shapes of solid patterns (upper row) or 

 between those of different broken ones (lower row). (Courtesy, von Frisch: Bees. 

 Ithaca, N.Y., Cornell University Press, 1950.) 



sucks up the sugar water (placed there for the experiment), goes back to the 

 hive and walks onto the comb among hundreds of bees. First, she delivers 

 sugar water to some of them. After that she dances, turns a circle to the left, 

 turns one to the right, repeats this in one spot for a half minute or more, then 

 goes to another place and dances again. During the dances the nearby bees 

 become more and more excited. They troop behind the dancer and extend 

 their antennae toward her. Suddenly one of them turns away and leaves the 

 hive; others follow and the watcher soon sees them at the feeding place. 



Workers that have been collecting food at more distant places perform the 

 wagging dance (Fig. 30.28). They run a little way straight forward wagging 

 the abdomen then turn a circle to the left, retrace the straight hne wagging 



Fig. 30.27. Sense organs on one of the eight outer or distal segments of the 

 antennae of honeybees. Sections through the chitinous body covering (black), the 

 cells which produce it and the sense organs. Left, section through an organ of 

 touch, highly magnified. Center and right, the organs of smell. Processes from 

 nerve cells, in the cluster, end beneath a very thin part of the chitin and can be 

 stimulated by scented substances diffusing through it. (Courtesy, von Frisch: Bees. 

 Ithaca, N.Y., Cornell University Press, 1950.) 



