Sexual Selection as an Engine for Adaptation to Changing Environments

• Applicant: Professor Dr. Klaus Reinhardt, since 7/2019
• Subject Area: Evolution, Anthropology
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 412226825

Sexual selection is widely acknowledged as a potent selective force driving the evolution of reproductive behaviours, physiologies and morphologies. However, the extent to which sexual selection affects the adaptation to novel environments remains an unresolved conundrum in evolutionary biology. Theory predicts that sexually selected traits capture the genetic information encoding condition at a multitude of loci across the genome. This postulated condition-dependence of sexual traits implies that sexual selection targets the same genes as natural selection and therefore promotes the adaptation to novel environments. By contrast, another school of thoughts predicts that sexual selection leads to sexual conflict, which often comes at a demographic cost and thereby impedes the population’s adaptive potential to cope with novel environments. Given this contradictory theoretical framework and the lack of rigorous empirical tests of the interplay between sexual and natural selection, it is currently impossible to evaluate the role of sexual selection for the adaptation to changing environments. The here-proposed project aims to fill this gap (i) by testing condition-dependence of sexually selected traits across the animal kingdom, (ii) by quantifying the effect of the environment on sexual selection, and (iii) by examining the interplay between sexual and natural selection. This will be achieved by using the Red-flour beetle Tribolium castaneum as a model system and a blend of meta-analyses, quantitative genetics, experimental evolution, and state-of-art Next Generation Sequencing techniques. Specifically, I propose to carry out a meta-analysis testing for heightened condition-dependence of sexually selected traits across animals. Moreover, I will explore how environmental factors affect the mode of sexual selection including experimental tests of environment-dependent genetic variance-covariance matrices and multivariate fitness surfaces of sexually selected traits. Finally, I will combine experimental evolution and genomics to test the hypothesis that sexual selection and natural selection act in concert to purge deleterious alleles and are targeting primarily the same loci. These experimental approaches aim to achieve a major breakthrough in sexual selection research by providing the most powerful and comprehensive test of the working hypothesis that sexual selection aligns with natural selection and therefore promotes to adaptation to novel environments.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Tim Janicke, until 7/2019