Prof. Dr. Susanne Foitzik

Institut für Organismische und Molekulare Evolutionsbiologie

Universität Mainz

<link file:243737 download internal link in current>Flyer here...

The evolution and genetic basis of behaviour in ants: Division of labour and the role of parasitism

Social insects and in particular ants show fascinating behaviours, from slavery, over social immunity to an effective division of labour in their societies. In this talk, I will give insights into the evolution and molecular basis of behaviour in ants and present recent results that reveal which genes or pathways are involved. For example, division of labour among workers is age dependant in Temnothorax ants, and using transcriptome analyses we could identify candidate genes, which control this behavioural transition. RNAi-mediated knockdown of a brood care gene, vitellogenin-6, showed that division of labour is indeed controlled via response thresholds, which shift with gene expression. This gene also plays a role in infection as it is overexpressed in cestode-infected workers. Here it appears to control the association of infected workers with the brood, which might be in the parasites’ interest as it could increase its transmission to the final host. Another interesting trait of infected workers is an increase in longevity and first evidence suggest that this is mediated via a reduction in oxidative stress. Whether these parasite-induced phenotypic alterations are indeed the result of parasite manipulation is still an open question, which might be answered by studying how the parasite interferes with its host gene expression. Finally we investigate the evolution of slavery in ants and can show, which genes are differently expressed during slave raids and host defence in three slavemakers and their three hosts. We could functionally characterize some of these candidates using RNAi. Selection analyses reveal that different genes are under selection in independent origins of slavery, suggesting convergent evolution of this fascinating behaviour.