|SREL Reprint #2246|
MAINTENANCE OF POLYMORPHISM PROMOTED BY SEX-SPECIFIC FITNESS PAYOFFS
HOWARD H. WHITEMAN
Phenotypic plasticity occurs when a single genotype produces continuous or discrete phenotypic variation in different environments (Lloyd 1984; West-Eberhard 1989; Stearns 1992-1 Roff 1992; Schemer 1993). Phenotypic variation and plasticity are fundamental to our understanding of evolutionary processes, yet the mechanisms that produce and maintain them remain unclear (Via and Lande 1985; Schlichting 1986; West-Eberhard 1989; Moran 1992; Schemer 1993). Environmentally cued polymorphisms, in which two or more alternative phenotypes are produced in response to environmental variation, are some of the most extreme examples of phenotypic plasticity. Such polymorphisms are ideal for studying the evolutionary mechanisms maintaining phenotypic plasticity and variation because each alternative has discrete fitness consequences and is likely maintained as a result of' selection (Caswell 1983; Smith-Gill 1983; WestEberhard 1986). Thus, studying the evolution of these polymorphisms may help clarify the role of the environment in the production and maintenance of plasticity.
Key words-Facultative paedomorphosis, fitness, polymorphism, sex, sex ratio.
SREL Reprint #2246
Whiteman, H.H. 1997. Maintenance of polymorphism promoted by sex-specific fitness payoffs. Evolution 51:2039-2044.