Author
JERAL, J - UNIV OF COLORADO BOULDER | |
BREED, M - UNIV OF COLORADO BOULDER | |
Hibbard, Bruce |
Submitted to: Physiological Entomology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/9/1996 Publication Date: N/A Citation: N/A Interpretive Summary: Nestmate recognition plays a key role in the biology of many social insects. Recognition systems are particularly important in prevention of thievery. Workers of the tropical ant species we worked with exhibit a system of thievery of food between colonies; thief ants enter other colonies, intercept food, and carry it to their own colony. Insects have layer of waxy chemicals on the outside of their exoskeleton that helps to prevent moisture loss. The type of chemicals found differs between insect species, and even between individuals of the same species. Social insects from within the same colony generally have a similar surface chemistry profile. We analyzed thief ants, ants from the thief's colony, and ants from the colony being robbed for their surface chemical profile. Thief ants had significantly lower total quantities of surface compounds than non-thieves. The reduction in surface compounds on thieves suggests that thievery is aided by inhibition of either synthesis or acquisition of its home colony's recognition cues. Statistical analysis of the quantities of surface compounds on different types of ants supports the hypothesis that both inhibition of a thief's home colony cues and acquisition of its target colony's cues play a role in successful thievery. Elucidation of this behavior and signaling system contributes to our understanding of the basis for apparent social activity in ant colonies. Technical Abstract: Workers of a tropical ponerine ant, Ectatomma ruidum (Roger), exhibit a system of intercolonial thievery for food; thief ants enter conspecific colonies, intercept food, and carry it to their own colony. We analyzed thief ants, ants from the thief's colony, and ants from the colony being robbed to determine if changes in cuticular profiles could facilitate entry by thieves into a target colony. Thief ants have significantly lower total quantities of dichloromethane soluble cuticular compounds than non-thieves. The reduction in cuticular compounds on thieves suggests that thievery is facilitated by inhibition of either synthesis or acquisition of its home colony's recognition cues. Five of the fifteen compounds differed significantly in their relative proportion among colonies. Principle components analysis lend support the hypothesis that both inhibition of a thief's home colony cues and acquisition of its target colony's cues play a role in successful thievery. |