A trade-off between precopulatory and postcopulatory trait investment in male cetaceans

• DOI: 10.1111/evo.12676
• Publication Date: 2015-05-01T09:42:15Z
• Authors: James P. Dines; Sarah L. Mesnick; Katherine Ralls; Laura May-Collado; Ingi Agnarsson; Matthew D. Dean
• Keywords: Trait; Trade-off; Sexual dimorphism

Mating with multiple partners is common across species, and understanding how individual males secure fertilization in the face of competition remains a fundamental goal evolutionary biology. Game theory stipulates that have fixed budget for reproduction can lead to trade-off between investment precopulatory traits such as body size, armaments, ornaments, postcopulatory testis size spermatogenic efficiency. Recent theoretical empirical studies shown if monopolize access females, they will invest disproportionately less traits. Using phylogenetically controlled comparative methods, we demonstrate 58 cetacean species most prominent sexual dimorphism shape, teeth, tusks, singing significantly relative testes mass. In support predictions, these tend show evidence male contests, suggesting there opportunity winners females. Our approach provides robust dataset which make predictions about mating strategies many adequate behavioral observations do not exist.