FOR 2281: Sociality and the reversal of the fecundity-longevity trade-off

Basic data for this project

Description

Why do animals age? This is a question of fundamental importancefor scientists and the general public alike. Yet despite its importancethis puzzle is still not well understood. Central for ageing is thefecundity/longevity trade-off: in almost all animals an increase inreproduction is traded-off against a shortened lifespan. Majorexceptions are social insects, such as honey bees, ants and termites.Their queens are amongst the most fecund and the most long-livinginsects and reproduction increases longevity. This makes socialinsects promising new ageing models which we explore within ourresearch unit. Our overarching goal is to understand how and why thefecundity/longevity trade-off is reversed in social insects and how thisevolved convergently in independent lineages. During the first fundingphase we studied ageing from an ultimate and proximate perspective,covering three lineages of social insects (ants, bees, and termites)and using Drosophila melanogaster as a solitary control. Thisapproach allowed us to develop the first evolutionary ageing modelstailored to social insects which identified crucial variables forexplaining queen longevity. Additionally, we found promisingcandidate genes and pathways associated with ageing and thereversal of the fecundity/longevity trade-off. Our results suggest thatconvergent evolution at the phenotypic level was accomplished bydifferent molecular changes across social species but along the samepathways. During the second funding phase we will explore theseresults in more detail. We have three Foci: The projects of Focus A‘Synthesis’ will undertake comparative studies and analyses to obtainan overarching view of the general and idiosyncratic mechanisms ofthe reshaping of the fecundity/longevity trade-off. Within Focus B‘Regulators’, projects will perform functional experiments and in-depthanalyses to reveal the pathways and networks and their re-wiring,underlying the reshaping of the fecundity/longevity trade-off usingselected species. The projects of Focus C ‘Transitions’ willcomparatively study ageing and the reshaping of thefecundity/longevity trade-off along multiple social transitions withinbees, ants and termites to uncover how and why sociality changedthe trade-off. Combined, we thus aim at gaining fundamental insightsinto the mechanisms and causes of ageing and sociality. Byuncovering the basis of the apparent escape from the commonfecundity/longevity trade-off, we expect to understand better thefundamental biological rules governing fecundity, longevity,senescence, and health.