Optional gamergates in the queenright ponerine ant Gnamptogenys striatula Mayr

Abstract

Ponerine ants display a number of social structures to which particular behaviours are associated. In the ponerine ant species Gnamptogenys striatula Mayr, queens occur and queenright colonies are functionally polygynous. However, some workers are capable to mate and to produce their own worker offspring. These gamergates appear several days after the queens are experimentally removed, allowing some workers to adopt a sexual calling posture inside the nest. At that time, other workers get outside the nest to collect males in the arena and carry them back into the colony. There, these males are groomed before they can mate with sexual calling workers. As for queens, several gamergates may coexist in a same colony. The social profile of gamergates is similar to those of nurses and they stay closer to the egg piles.

Genetic diversity, worker size polymorphism and division of labour in the polyandrous ant Cataglyphis cursor

“…Thus, genotypic variability does not appear as a necessary condition for intracolonial diversity and task specialization in C. cursor. This contrasts with the several cases where genetic variability among workers has been shown to influence division of labour in insect societies (honeybee: Frumhoff & Baker 1988;Robinson & Page 1988;Fuchs & Schade 1994;Page et al 1995;Kryger et al 2000;termites: Goodisman & Crozier 2003;ants: Stuart & Page 1991;Snyder 1992;Blatrix et al 2000;Julian et al 2002;Bargum et al 2004;Schwander et al 2005). The lack of genetic polyethism in C. cursor also suggests that within-colony genetic diversity is not associated with increased task efficiency and/or colony performance in this species.…”

“…For instance, workers belonging to certain patrilines show a higher tendency to perform certain tasks such as foraging, recruiting, guarding, stinging, or nest-cleaning in the honeybee (Frumhoff & Baker 1988;Robinson & Page 1988, 1989Page et al 1989Page et al , 1995Oldroyd et al 1994), wasps (O'Donnell 1998), and in a few ant species (Stuart & Page 1991;Hughes et al 2003). Similarly, a significant genetic component to division of labour has been reported in ant colonies headed by multiple queens (polygyny), with workers belonging to different matrilines showing a different propensity to perform distinct tasks (Snyder 1992;Blatrix et al 2000;Julian et al 2002).…”

Cuticular Hydrocarbons Provide Reliable Cues of Fertility in the Ant Gnamptogenys striatula

“…Removing queens or gamergates from nests results in sexual calling and egg laying by some of the virgin workers inside the nest. The labor workers then transport nearby males to the nest, where the males will mate with any worker that assumes the sexual-calling position (Blatrix and Jaisson, 2000). The ability of workers to mate after loss of the queen or gamergates renders the colonies potentially everlasting.…”

“…In some species, dominance behavior appears to be lacking altogether, even after colonies have been orphaned (Gnamptogenys striatula, Blatrix and Jaisson, 2000;Pachycondyla berthoudi, Peeters andCrewe, 1985, 1984;Sledge et al, 2001;P. krugeri, Wildman and Crewe, 1988;Platythyrea lamellosa, Villet et al, 1990;P.…”

“…We used the facultatively queenless ant G. striatula (Blatrix and Jaisson, 2000) to examine the cuticular chemistry of fertile and infertile individuals with respect to different stages of ovarian development and mating status. As predicted, we showed that active egg layers have a unique cuticular hydrocarbon profile that, thus, can provide nestmates with reliable signals of fertility.…”