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

• Subject Area: Biology
• Term: since 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 261675780

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.

• DFG Programme: Research Units
• International Connection: Brazil, Mexico, Netherlands, South Africa, Switzerland, USA

Projects

• A comparative approach to the fecundity/longevity trade-off across two origins of eusociality in the bees (Applicant Paxton, Robert )
• Comparative Analysis of the Molecular Mechanisms of Ageing in Flies and Bees (Applicant Fricke, Claudia )
• Coordination Funds (Applicant Korb, Judith )
• Defying senescence – The causes of death and the costs of living of ant queens (Applicant Oettler, Jan )
• Differential regulation of genes, isoforms and networks during ageing in social insects (Applicant Bornberg-Bauer, Erich )
• Functional basis of the fecundity - longevity reversal in the ant Temnothorax rugatulus (Applicants Feldmeyer, Barbara ;  Foitzik, Susanne )
• Reversal of the fecundity / longevity trade-off across social transitions in ants (Applicants Foitzik, Susanne ;  Libbrecht, Ph.D., Romain ;  Nehring, Ph.D., Volker )
• The fecundity/longevitiy tradeoff in a clonal ant (Applicant Heinze, Jürgen )
• The fecundity/longevity trade-off in a clonal ant (Applicant Bernadou, Ph.D., Abel )
• The genomic tool box to transform a short lived social bee into a long lived social parasite (Applicant Moritz, Robin F. A. )
• The Physiological and Metabolic Basis of the Fecundity/Longevity Trade-Off in Drosophila (Applicant Flatt, Thomas )
• Towards testable quantitative models for the evolution of caste specific ageing part II: integrating theory and experiment (Applicant Pen, Ido )
• Uncovering the functional basis of the reversal of the fecundity/longevity trade-off in a termite (Applicant Korb, Judith )
• Why and how does sociality change the fecundity/longevity trade-off in termites? (Applicants Korb, Judith ;  Pen, Ido )

• Spokesperson: Professorin Dr. Judith Korb