Data from: Strict monandry in the ponerine army ant genus Simopelta suggests that colony size and complexity drive mating system evolution in social insects

Altruism in social insects has evolved between closely related
full-siblings. It is therefore of considerable interest why some groups
have secondarily evolved low within-colony relatedness, which in turn
affects the relatedness incentives of within-colony cooperation and
conflict. The highest queen mating frequencies, and therefore among the
lowest degrees of colony relatedness, occur in Apis honeybees and army
ants of the subfamilies Aenictinae, Ecitoninae, and Dorylinae, suggesting
that common life-history features such as reproduction by colony fission
and male biased numerical sex-ratios have convergently shaped these mating
systems. Here we show that ponerine army ants of the genus Simopelta,
which are distantly related but similar in general biology to other army
ants, have strictly monandrous queens. Preliminary data suggest that
workers reproduce in queenright colonies, which is in sharp contrast to
other army ants. We hypothesize that differences in mature colony size and
social complexity may explain these striking discrepancies.