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DIETRICH SCHNEIDER 

 FOOD DETECTION BY OLFACTORY RECEPTORS 



As is well known, the olfactory sense serves insects in different ways. 

 Many insects depend largely upon their olfactory receptors to find food or 

 places to lay eggs. A good example is the worker honeybee which is 



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Fig. 2. A, Method of recording action potentials with glass capillary electrodes 

 from a single sensillum basiconicum. B, Recording from Sphinx pinastri 

 (Sphingidae) stimulated with terpineol. Three units are active. Upper (D-C) 

 trace shows receptor potential with nerve impulses ; lower (R-C) trace shows 

 only nerve impulses. Downward deflection indicates negative charging of the 

 recording electrode (from Schneider and Lacher, unpublished). 



directed to a large extent by olfactory stimuli during foraging. Rather 

 unexpectedly the bee was shown to have a sense of smell somewhat similar 

 to man (v. Frisch, 1921). This broadly developed sense does not show 

 extreme sensitivity but enables the animal to distinguish between a large 

 spectrum of odours. 



Many food specialists among the insects also exist. A well known 

 example is the carrion-beetle of the genus Necrophorus (cf. Dethier, 1947). 



