CAUSEX · Unified theory of sexual selection

Sexual selection and sexual strategies include some of the most fascinating and widely-studied phenomena in evolutionary biology. Yet they are also among the most debated and disputed topics. Our ability to understand causal relationships and to fully engage with disagreements and controversies is limited by the disjointed nature of theory, which does not typically engage with the gamete level where central concepts are defined. CAUSEX will seek a common causal and mathematical structure that applies across models of sexual selection and sexual strategy, and engages explicitly with the defining aspects of sexes and sexual selection. This common foundation will be used to bind together and reconstruct central aspects of classical sexual selection theory, to scrutinise relationships between modelling methods, and to develop new models. In doing so, we will also develop biophysical models (fertilisation functions) which explicitly link gamete level processes to fitness. The overall aim is a conceptually and causally coherent theory which is clearly linked to the gamete level. The unification of a disjointed and controversial field will address unresolved challenges and clarify empirical predictions, and will be a major breakthrough in evolutionary biology.