Segregation of colony odor in the desert ant Cataglyphis niger

Citation
S. Lahav et al., Segregation of colony odor in the desert ant Cataglyphis niger, J CHEM ECOL, 27(5), 2001, pp. 927-943
Citations number
24
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Environment/Ecology
Journal title
JOURNAL OF CHEMICAL ECOLOGY
ISSN journal
0098-0331 → ACNP
Volume
27
Issue
5
Year of publication
2001
Pages
927 - 943
Database
ISI
SICI code
0098-0331(200105)27:5<927:SOCOIT>2.0.ZU;2-3
Abstract
There are two separate, and presumably opposing, processes that affect colo ny odor in the desert ant Cataglyphis niger: (1) biosynthesis and turnover of these chemicals by individual ants, and (2) homogenization of colony odo r through exchange of cues. The first increases signal variability; the lat ter decreases it. The impact of these factors was tested by splitting colon ies and monitoring the profile changes occurring in the postpharyngeal glan ds (PPG) and cuticular hydrocarbons. From each of two polygynous nests four daughter colonies were formed, three monogynous and one queenless. Thereafter, 10 ants from each were randomly selected each month, for three successive months, for analyses of their PPG and cuticular hydrocarbons. From two colonies we also obtained ants from a known matriline. Over time, there was a shift in hydrocarbon profiles of b oth the PPG and cuticular washes in each of the tested colonies. Moreover, by subjecting selected hydrocarbon constituents to a discriminant analyses based on their relative proportions, all of the daughter colonies (queenrig ht and queenless) were distinguishable from each other and from their respe ctive mother colonies. In each of the queenright daughter colonies, the que en profile was indiscriminable from that of the workers and often was in th e center of the group. Full sisters were clearly distinguishable from their nestmates, emphasizing the genetic versus environmental processes that gov ern colony odor. The effect of time was always superior to the separation e ffect in contributing to odor segregation. Comparison of the Mahalanobis di stances indicated that the shift in hydrocarbon seems to proceed along para llel lines rather than in divergence. However, there was no overt aggressio n between ants that originated from the different subgroups in dyadic encou nters. It appears that in this species a three-month separation period is n ot sufficient to change the hydrocarbon profile beyond the recognition thre shold.