Adult sex ratio variation: implications for breeding system evolution.
Adult sex ratio (ASR) exhibits immense variation in nature, although neither the causes nor the implications of this variation are fully understood. According to theory, the ASR is expected to influence sex roles and breeding systems, as the rarer sex in the population has more potential partners to mate with than the more common sex. Changes in mate choice, mating systems and parental care suggest that the ASR does influence breeding behaviour, although there is a need for more tests, especially experimental ones. In the context of breeding system evolution, the focus is currently on operational sex ratios (OSRs). We argue that the ASR plays a role of similar importance and urge researchers to study the ASR and the OSR side by side. Finally, we plead for a dynamic view of breeding system evolution with feedbacks between mating, parenting, OSR and ASR on both ecological and evolutionary time scales.
Biodiversity Lab, Department of Biology & Biochemistry, University of Bath, Bath, UK; Theoretical Biology, Centre for Ecological and Evolutionary Studies, University of Groningen, Groningen, The Netherlands; Behavioural Ecology and Self-organization, Centre for Ecological and Evolutionary Studies, University of Groningen, Groningen, The Netherlands.
T
T
Székely
F J
FJ
Weissing
J
J
Komdeur
D000220:Adaptation, Biological / Q000502:physiology*; D000818:Animals; D005075:Biological Evolution; D008954:Models, Biological; D012744:Sex Ratio; D012726:Sexual Behavior, Animal / Q000502:physiology*; D012741:Sexual Maturation / Q000502:physiology; D013045:Species Specificity
adult sex ratio; mate choice; mating system; operational sex ratio; parental care