The status of the conditional evolutionarily stable strategy

Larval growth in polyphenic salamanders: making the best of a bad lot

“…Environmentally-cued polymorphisms (polyphenisms), which occur when discretely different phenotypes develop from genotype by environment interactions, provide excellent opportunities for understanding the mechanisms producing and maintaining phenotypic variation and plasticity (West-Eberhard 1986, 2003Hazel et al 1990Hazel et al , 2004Scheiner 1993;Roff 1996;Relyea 2002;Tomkins and Hazel 2007). Polyphenisms provide model systems for the study of phenotypic variation because: (1) the trait of interest has a direct environmental component; (2) alternative phenotypes are often distinct and easily distinguished; and (3) they are likely to be a direct result of selection (Caswell 1983;Smith-Gill 1983).…”

“…Polyphenisms provide model systems for the study of phenotypic variation because: (1) the trait of interest has a direct environmental component; (2) alternative phenotypes are often distinct and easily distinguished; and (3) they are likely to be a direct result of selection (Caswell 1983;Smith-Gill 1983). Documenting the ecological and evolutionary contexts that produce and maintain polyphenisms is critical for understanding their role in speciation, life history evolution, the maintenance of biodiversity, and the evolution of plasticity (West-Eberhard 1986, 2003Hazel et al 1990;Via 2001;Denoël et al 2005;Emlen et al 2007;Pfennig et al 2007Tomkins and Hazel 2007;Pfennig and McGee 2010).…”

Ejaculate Allocation and Sperm Competition in Alternative Reproductive Tactics of Salmon and Trout: Implications for Aquaculture

“…Recently, phenotypic plasticity in sperm production as a response to sperm competition risk was emphasized (Rudolfsen et al 2006;Cornwallis & Birkhead 2007;Pizzari et al 2007;Ota et al 2010). Importantly for conditional strategies to evolve, environmental cue affecting gonad maturation must be reliable, whereas finesses of the alternative maturation life histories are not necessarily equal (Tomkins & Hazel 2008). Each reaction norm can be understood as different conditional strategy.…”

“…early versus late maturing phenotypes) (Tomkins & Hazel 2008). Above equation implies that stronger additive genetic variation for the maturation trait, the stronger response to selection should be over an environmental gradient.…”

“…A genotype x environment reaction exists in the population if slopes of alternative fitness functions over environmental gradient cross. If slopes of fitness functions do not cross, male tactic may depend on individual male condition, which is commonly influenced by developmental constraints (Tomkins & Hazel 2008). These conditional reproductive tactics are central in sexual selection.…”