3 : 5/ Special Uses of Hearing and Vision 63 



At least one European plover, hatched from its egg in isolation from 

 all other birds, developed with a memory of the terrain over which its 

 species migrated. This bird, at the start of the fall season, became 

 extremely restless in captivity but made no consistent attempt to fly in 

 any given direction. When it was placed in the Paris Planetarium with 

 the proper skyline and the proper orientation of stars for that time of 

 year, the bird attempted to fly along the migration course characteristic 

 of its species. It simulated flight southward to the Mediterranean shore, 

 then turned eastward and simulated flight around the Mediterranean to 

 Africa. By simulated day it used the skyline to navigate, and on simu- 

 lated clear nights it used the position of the stars. A built-in "clock" 

 (time sense) enabled the bird to "compute" the proper position of the 

 stars at that time of night for the Mediterranean shore at that season of 

 year. 



There is nothing to indicate that similar built-in, inherited memories 

 exist in all migratory birds. Nor is there any reason to guess whether 

 or not some inherit their memories and others acquire them on their 

 first flights. (Migration experiments do give one reason to doubt the 

 carry-over of learning experiments from birds to man.) Birds use their 

 visual sensations in migrating in a very special way which man is not 

 adapted to emulate, except through his artifacts such as the "migrating" 

 airplane. 



REFERENCES 



A large portion of the material in this chapter was based on the experimental 

 work of D. R. Griffin and his co-workers. A pleasant review of this work, on 

 a high, technical level, but written in an entertaining fashion, is his book: 



1. Griffin, D. R., Listening in the Dark : The Acoustic Orientation of Bats and Men 

 (New Haven, Connecticut: Yale University Press, 1958). This book 

 contains 386 pages of text as well as 467 references, which are pertinent 

 to the present chapter. 



Two shorter articles are in Scientific American: 



2. Griffin, D. R., "Bird Sonar" 190: 78-83 (March 1954). 



3. Griffin, D. R., "More About Bat 'Radar'" 199: 40-44 (Jan. 1958). 



The homing of bees and ants is discussed in : 



4. Fraenkel, G. S., and D. L. Gunn, Orientation of Animals : Kinesis, Taxes and 

 Compass Reactions (New York, N.Y. : Oxford University Press, 1940). 



5. von Frisch, Karl, Dancing Bees: An Account of the Life and Senses of the Honey 

 Bee. Translated by Dora Use (London, England: Methuen and Com- 

 pany, Ltd., 1954). 



