Bidirectional Shifts in Colony Queen Number in a Socially Polymorphic Ant Population

Purcell, Jessica; Chapuisat, Michel

doi:10.1111/evo.12010

Cited by 31 publications

(42 citation statements)

References 86 publications

(183 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, we seek biogeographic patterns in the altitudinal distribution of colony queen number of a socially polymorphic ant species across multiple transects in geographically distant drainage basins. Our study species, the Alpine silver ant Formica selysi, exhibits a mix of monogynous and polygynous colonies within a single population (Chapuisat et al 2004;Purcell & Chapuisat 2013). As in other polymorphic species, each form is associated with a suite of behavioural and morphological traits (Keller 1993).…”

Section: Introductionmentioning

confidence: 98%

Social structure varies with elevation in an Alpine ant

2015

Self Cite

View full text Add to dashboard Cite

Insect societies vary greatly in social organization, yet the relative roles of ecological and genetic factors in driving this variation remain poorly understood. Identifying how social structure varies along environmental gradients can provide insights into the ecological conditions favouring alternative social organizations. Here, we investigate how queen number variation is distributed along elevation gradients within a socially polymorphic ant, the Alpine silver ant Formica selysi. We sampled low- and high-elevation populations in multiple Alpine valleys. We show that populations belonging to different drainage basins are genetically differentiated. In contrast, there is little genetic divergence between low- and high-elevation populations within the same drainage basin. Thus, elevation gradients in each of the drainage basins represent independent contrasts. Whatever the elevation, all well-sampled populations are socially polymorphic, containing both monogynous (= one queen) and polygynous (= multiple queen) colonies. However, the proportion of monogynous colonies per population increases at higher elevation, while the effective number of queens in polygynous colonies decreases, and this pattern is replicated in each drainage basin. The increased prevalence of colonies with a single queen at high elevation is correlated with summer and winter average temperature, but not with precipitation. The colder, unpredictable and patchy environment encountered at higher elevations may favour larger queens with the ability to disperse and establish incipient monogynous colonies independently, while the stable and continuous habitat in the lowlands may favour large, fast-growing polygynous colonies. By highlighting differences in the environmental conditions favouring monogynous or polygynous colonies, this study sheds light on the ecological factors influencing the distribution and maintenance of social polymorphism.

show abstract

Section: Introductionmentioning

confidence: 98%

Social structure varies with elevation in an Alpine ant

2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…For example, both queen number and queen mating frequency may vary greatly between species, and even within species in a population. Colonies may be headed by a single queen (monogynous) or by two or more queens (polygynous) (Bourke and Franks, 1995;Crozier and Pamilo, 1996;Purcell and Chapuisat, 2013). Species may also vary in the number of males with which the queen(s) mate, from strict monandry to high levels of polyandry .…”

Section: Introductionmentioning

confidence: 99%

At the brink of supercoloniality: genetic, behavioral, and chemical assessments of population structure of the desert ant Cataglyphis niger

et al. 2014

View full text Add to dashboard Cite

† These authors have contributed equally to this work.The nesting habits of ants play an important role in structuring ant populations. They vary from monodomy, a colony occupies a single nest, via polydomy, a colony occupies multiple adjacent nests, to supercoloniality, a colony spans over large territories comprising dozen to thousands nests without having any boundaries. The population structure of the desert ant Cataglyphis niger, previously considered to form supercolonies, was studied using genetic, chemical, and behavioral tools in plots of 50 × 50 m at two distinct populations. At the Palmahim site, the plot comprised 15 nests that according to the genetic analysis constituted three colonies. Likewise at the Rishon Leziyyon site 14 nests constituted 5 genetic colonies. In both sites, both chemical analysis and the behavioral (aggression) tests confirmed the colony genetic architecture. The behavioral tests also revealed that aggression between colonies within a population was higher than that exhibited between colonies of different populations, suggesting the occurrence of the "nasty neighbor" phenomenon. In contrast to supercolony structure previously reported in another population of this species, the presently studied populations were composed of polydomous colonies. However, both the genetic and chemical data revealed that the inter-colonial differences between sites were larger than those within site, suggesting some within-site population viscosity. Thus, C. niger exhibits flexible nesting characteristics, from polydomy to supercoloniality, and can be considered at the brink of supercoloniality. We attribute the differences in population structure among sites to the intensity of intraspecific competition.

show abstract

“…Each individual was used in only a single experiment or trial in this study. This population has been monitored for over ten years [14], and large floods causing erosion and nest destruction have been observed during that time (Fig. S1 in File S1) [12].…”

Section: Methodsmentioning

confidence: 99%

Ant Brood Function as Life Preservers during Floods

et al. 2014

Self Cite

View full text Add to dashboard Cite

Social organisms can surmount many ecological challenges by working collectively. An impressive example of such collective behavior occurs when ants physically link together into floating ‘rafts’ to escape from flooded habitat. However, raft formation may represent a social dilemma, with some positions posing greater individual risks than others. Here, we investigate the position and function of different colony members, and the costs and benefits of this functional geometry in rafts of the floodplain-dwelling ant Formica selysi. By causing groups of ants to raft in the laboratory, we observe that workers are distributed throughout the raft, queens are always in the center, and 100% of brood items are placed on the base. Through a series of experiments, we show that workers and brood are extremely resistant to submersion. Both workers and brood exhibit high survival rates after they have rafted, suggesting that occupying the base of the raft is not as costly as expected. The placement of all brood on the base of one cohesive raft confers several benefits: it preserves colony integrity, takes advantage of brood buoyancy, and increases the proportion of workers that immediately recover after rafting.

show abstract

Bidirectional Shifts in Colony Queen Number in a Socially Polymorphic Ant Population

Cited by 31 publications

References 86 publications

Social structure varies with elevation in an Alpine ant

Social structure varies with elevation in an Alpine ant

At the brink of supercoloniality: genetic, behavioral, and chemical assessments of population structure of the desert ant Cataglyphis niger

Ant Brood Function as Life Preservers during Floods

Contact Info

Product

Resources

About