Selection and phenotypic plasticity in evolutionary biology and animal breeding (original) (raw)

2002, Livestock Production Science

This paper reviews models for phenotypic plasticity in evolutionary genetics and animal breeding and show how those 21 models are connected. Environmental differences often lead to systematic phenotypic differences: phenotypic plasticity. 22 42 6 254-2219. 7 E-mail address: g.dejong@bio.uu.nl (G. de Jong). ent phenotypes in different environments. Phenotypic 43 1 0301-6226 / 02 / $ -see front matter  105 61 breeding is to include fixed effects, e.g., herd-year-composed from probability of survival, number of 106 62 season effects, into the model for breeding value offspring, mating success, longevity, and other so-107 63 estimation, and subsequently treat performance in called life-history characters. An individual's fitness 108 64 different environments (e.g., herds) as the same trait. depends upon its phenotype and the genotypic 109 65 128 84 Here, we shall first give an overview of the existence of a covariance between phenotype and 129 85 models of the evolution of phenotypically plastic fitness can be expressed in a selection gradient. A 130 86 quantitative traits as found within evolutionary biolo-selection gradient equals the partial derivative of 131 87 gy. The emphasis here will be on the different fitness with respect to the trait-that is, how fast 132 88 representation by the various models, as the models fitness changes with any change in trait value. A fast 133 89 themselves are straightforward applications of the change of fitness with trait value, i.e., a steep 134 90 general model for simultaneous selection on a num-selection gradient, implies strong selection. 135 91 ber of quantitative traits. Secondly, we will connect In accordance with the usage in evolutionary 136 1296 1259 converts into the product of the genetic variance and that S5cov(w ,z)5E(w z)5(12p)E(w zuz,t)1 1297 z z z 21 1260 the selection gradient of mean fitness towards mean pE(w zuz.t)501pis p , giving 1298 z z 1261 genotypic value. This yields