Flexible colony-founding strategies in a socially polymorphic ant

Abstract

Keywords:ant colony founding dispersal Formica selysi queen number social evolution social insect social structureIn social insects the number of queens per nest varies greatly. One of the proximate causes of this variation may be that queens produced by multiple-queen colonies are generally smaller, and might thus be unable to found new colonies independently. We examined whether the social origin of queens and males influenced the colony-founding success of queens in the socially polymorphic ant Formica selysi. Queens originating from single-queen and multiple-queen colonies had similar survival rates and colony-founding success, be they alone or in two-queen associations. During the first 5 months, queens originating from single-queen colonies gave rise to more workers than queens originating from multiplequeen colonies. Pairs of queens were also more productive than single queens. However, these differences in productivity were transient, as all types of colonies had reached a similar size after 15 months. Mating between social forms was possible and did not decrease queen survival or colony productivity, compared to mating within social forms. Overall, these results indicate that queens from each social form are able to found colonies independently, at least under laboratory conditions. Moreover, gene flow between social forms is not restricted by mating or genetic incompatibilities. This flexibility in mating and colony founding helps to explain the maintenance of alternative social structures in sympatry and the absence of genetic differentiation between social forms. Ó

Nesting patterns, ecological correlates of polygyny and social organization in the neotropical arboreal ant Odontomachus hastatus (Formicidae, Ponerinae)

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Prospecting precedes dispersal and increases survival chances in cooperatively breeding cichlids

“…In highly social animals, the current and future social environment are important determinants of an individual's chances of surviving and reproducing. If reproductive skew within groups is large, dispersal of subordinates may be a means to enhance the chances of gaining direct fitness by joining another group (Cant, Otali, & Mwanguhya, 2001;Clutton-Brock, 1998;Daniels & Walters, 2000;Glander, 1992;Johannesen & Lubin, 1999;Reber, Meunier, & Chapuisat, 2010;Rood, 1987;Sharp, Simeoni, & Hatchwell, 2008).…”

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“…In some ant species, colony-founding alternatives correlate with queen morphology: large queens found independently while small queens found dependently (Buschinger and Heinze, 1992;Rüppell and Heinze, 1999), though this may not be true in every species (e.g. Reber et al, 2010). While the development of queen size has both genetic and environmental influences, one or the other may predominate.…”