2009/05/22 by Amy E. Dunham, Volker H. W. Rudolf · 1 citation
Agricultural and Biological Sciences · Psychology · #Animal Behavior and Reproduction #Primate Behavior and Ecology #Evolutionary Psychology and Human Behavior #Biology #Sperm competition #Monomorphism #Sexual selection #Sexual dimorphism #Receptivity #Mate choice #Zoology #Primate #Phylogenetic comparative methods #Ecology #Competition (biology) #Evolutionary biology #Phylogenetic tree #Mating
paper · doi:10.1111/j.1420-9101.2009.01768.x
openalex publication_date 2009/05/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/16
Some species have potential for intense mate competition yet exhibit little or no sexual size dimorphism, despite predictions from sexual selection theory. Using a conceptual model, we show the conditions for which passive mate guarding with copulatory plugs can be an alternative and more successful strategy to active (direct) guarding, reducing selection pressure on large male size. The model predicts that copulatory plugs in mammals should be favoured in species for which females have short sexual receptivity periods. Using data on 62 primate species and a phylogenetic regression approach, we show that, as predicted, copulatory plugs are negatively associated with degree of sexual dimorphism and females' sexual receptivity length. Penile spines are also significantly associated with plug use and short receptivity periods suggesting a possible offensive role in sperm competition. Results highlight that life-history characteristics, such as sexual receptivity lengths, may alter the costs and benefits of alternative male strategies and thus alter the strength of sexual selection.