Meeting Abstract

S11-2.4  Monday, Jan. 7  A reaction norm perspective on sex and mate choice AH-KING, Malin*; GOWATY, Patricia A.; Uppsala University; Univ. of California, Los Angeles Malin.Ah-King@gender.uu.se

Sex is often seen as an essentially discrete trait, ensuing certain characteristics and “roles”. However, sex and sexual characters and behaviors are reaction norms, that is all phenotypes emerge out of environmental interactions with pre-existing phenotypes. For example, sex-change may be induced by temperature, body size or social environment. Sex allocation in hermaphrodites is influenced by environmental factors. Though sex is not completely plastic. Reaction norms may be reversible or non-reversible, differ in their amount of plasticity, the rapidity of response to environmental factors and in the responsive time-frame. Also, sex (determination, characters and behavior) changes over evolutionary time, and so does the relative importance of genetic and environmental influence on the expression of a trait. Females are traditionally expected to be generally choosy in their mate choice and males to be indiscriminate. However, accumulating empirical evidence shows that mate choice is flexible in response to environmental, social and internal factors. Both males and females have been shown to shift between choosy and random mating in response to a number of environmental, demographic, social and internal factors. Empirical studies have investigated diverse factors (such as predation risk, density, OSR, encounter rate, chooser condition) causing mate choice flexibility, often as deviations from a general female and male pattern. In contrast, Gowaty and Hubbell (2005, 2009) argued that all individuals are flexible. The dynamic view of sex opens up new directions for future research. We suggest that we need to pay more attention to phenotypes – morphological, physiological, and behavior – as developmentally plastic and/or individually flexible in relation to sex and sex-linked traits.