Testing the reproductive groundplan hypothesis in ants (Hymenoptera: Formicidae)

The evolution of complex societies with obligate reproductive division of labour represents one of the major transitions in evolution. In such societies, functionally sterile individuals (workers) perform many of fitness-relevant behaviours including allomaternal ones, without getting any direct fitness benefits. The question of how such worker division of labour has evolved remains controversial. The reproductive groundplan hypothesis (RGPH) offers a powerful proximate explanation for this evolutionary leap. The RGPH argues that the conserved genetic and endocrinological networks regulating fitness relevant behaviour (e g. foraging and brood care) in their solitary ancestors have become decoupled from actual reproduction in the worker caste and now generate worker behavioural phenotypes. However, the empirical support for this hypothesis remains limited to a handful of species making its general validity uncertain. In this study we combine data from the literature with targeted samplin...