Numbers count: caste-specific component Allee effects and their interactions

Allee effects, positive relationships between fitness and the number or density of conspecifics, are surprisingly widespread and are of profound importance for understanding ecological dynamics. Lucque etal. (2013) provide the first explicit demonstration of Allee effects in a social insect. Using laboratory colonies of the Argentine ant, they show that there are component Allee effects of both workers and queens which interact with negative frequency-dependent effects. Such Allee effects are central to the ecology and evolution of social insects, the societies of which provide a rich, experimentally tractable resource for understanding the mechanisms and impact of Allee effects.