A CAUSE OF FEUD BETWEEN ANTS OF THE 



SAME SPECIES LIVING IN DIFFERENT 



COMMUNITIES. 



ADELE M. FIELDE. 



If the blood of several ants of the same species be shed upon a 

 morsel of sponge, the characteristic odor of the species is dis- 

 cernible upon the sponge, even by human nostrils. The odor 

 may be pungent, acid, acrid, or musty, or may be like that of an 

 animal or vegetable oil. Of the thirty-five hundred known 

 species of ants, probably each has its distinctive odor. 



Every ant recognizes its acquaintances through their odor 

 and its own sense of smell. It is violently hostile to all ants 

 bearing an unfamiliar scent, and is caressingly friendly with ants 

 whose odor it has always known. 



That ants of unlike species should be inimical one to another 

 is less strange than the fact that those of the same species and 

 variety, inhabiting the same localities, but living in different com- 

 munities, should be as intensely antipathetic as are those of dif- 

 ferent species. With a view to ascertaining the cause of the an- 

 imosity between such communities, I made in 1902, many ex- 

 periments l with Stenauunafiilviun, with results showing that the 

 odor of the ants changes with their age, and that ants will not 

 live amicably with those much older than any that inhabited the 

 nest in which they were hatched. 



If an ant be hatched in isolation, and the isolation be main- 

 tained until the ant has attained its adult strength and color, the 

 odor of its own body is this ant's sole criterion of proper ant- 

 odor, and it will affiliate with no ants other than those of the 

 same lineage and of nearly the same age as itself. It will affiliate 

 instantly with the queen-mother from whose egg it came and 

 whose odor it inherits, and will identify and caress that mother 

 though she be presented among five queens never before en- 



1 A. M. Fielde, " Notes on an Ant," Proceedings of the Academy of Sciences of 

 Philadelphia, December, 1902. 



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