van Dooren T J
Department of Biology, University of Antwerp, Belgium.
Proc Biol Sci. 2001 Feb 7;268(1464):279-87. doi: 10.1098/rspb.2000.1362.
Two versions of a model for the evolution of seasonal polyphenism investigate the evolution of reaction norm bifurcation and branching. The first version is without a specific submodel for morphological development and the second has an explicit developmental map. Version 1 is evolutionarily relatively unconstrained: (i) reaction norms are specified by matrices containing the probabilities of occurrence of environment-phenotype combinations, (ii) all conceivable reaction norm matrices are reachable through a sequence of mutations, and (iii) small as well as large mutational effects occur. This version is used to find the evolutionarily stable strategy favoured by the population ecology that is characterized by stabilizing viability selection with a cyclically fluctuating selection optimum. When the strength of selection is large and when the lag between initiation of development and selection on mature phenotype is not a multiple of half the period of the environmental cycle, a branching reaction norm evolves. In the second model version, branching reaction norms occur for certain parameter combinations of the developmental submodel, but the evolution of this pattern is often constrained. The evolutionary trajectory becomes trapped in a local selective optimum for the parameters of the developmental system. Substantial developmental noise evolves, but mutations that produce a selectively advantageous branching pattern do not occur from there.
一个关于季节性多型现象进化的模型有两个版本，它们研究反应规范分叉和分支的进化。第一个版本没有形态发育的特定子模型，第二个版本有明确的发育图谱。版本1在进化上相对不受限制：（i）反应规范由包含环境 - 表型组合出现概率的矩阵指定，（ii）所有可想象的反应规范矩阵都可以通过一系列突变达到，并且（iii）会出现小的和大的突变效应。这个版本用于找到种群生态学所青睐的进化稳定策略，其特征是具有周期性波动选择最优值的稳定生存能力选择。当选择强度大且发育开始与成熟表型选择之间的滞后不是环境周期一半的倍数时，会进化出分支反应规范。在第二个模型版本中，对于发育子模型的某些参数组合会出现分支反应规范，但这种模式的进化通常受到限制。进化轨迹会陷入发育系统参数的局部选择最优值。会进化出大量的发育噪声，但从那里不会发生产生选择性有利分支模式的突变。
