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Psyche 
[June 
tant in some other function. Simpson (1966) reported that the 
mandibular gland secretion repelled honey bees when it was added 
to a dish of sucrose syrup. This repellency probably depends on the 
content of 2-heptanone in the mandibular glands (Butler, 1966). 
Our study provides no evidence that the worker bees release their 
mandibular gland secretion when they detect ants. When the ant 
or odorous compound was removed, the defensive behavior stopped, 
and the bees resumed normal activity. This defensive response of 
honey bees toward ants described here may illustrate a situation 
where one species of insect appears to emit an alarm pheromone acting 
as a “Kairomone” (Brown et al., 1970) which releases defensive 
behavior for another species, and may also indicate that honey bees 
can react in several different ways to the same compound. 
SUMMARY 
Honey bees respond to ants and certain chemicals by turning away 
from the ants or chemicals, fanning the wings, and kicking the rear 
legs. This activity is believed to be a defense against ants invading 
the nest. Argentine ants are probably successful pests of bees be- 
cause they apparently have a low level of odor. 
ACKNOWLEDGEMENTS 
We thank Dr. Murray S. Blum, University of Georgia, for supply- 
ing us with Argentine ant workers and Dr. William L. Nutting, 
University of Arizona, for reading the manuscript. We also thank 
the Arizona Commission of Agriculture and Horticulture for prompt 
and courteous processing of our permit to bring these worker ants 
into Arizona for experimental purposes. 
Literature Cited 
Blum, M. S. 
1969. Alarm Pheromones. Ann. Rev. Entomol. 14: 57-80. 
Blum, M. S., F. Padovani, A. Curley, R. E. Hawk 
1969. Benzaldehyde: defensive secretion of a harvester ant. Comp. 
Biochem. Physiol. 29: 461-6. 
Blum, M. S., S. L. Warter, R. S. Monroe, J. C. Chidester 
1963. Chemical releasers of social behaviour — I. Methyl-n-amyl ketone 
in Iridomyrmex pruinosus (Roger) (Formicidae: Dolichoderinae) . 
J. Insect Physiol. 9: 881-5. 
Boch, R. and D. A. Shearer 
1967. 2-heptanone and 10-hydroxy-trans-dec-2-enoic acid in the mandib- 
ular glands of worker honey bees of different ages. Z. Vergleich. 
Physiol. 54:1-11. 
