Environmental stress and evolution: a theoretical study.
Environmental stress and evolution: a theoretical study.
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环境压力与进化：理论研究。
DOI：
10.1007/978-3-0348-8882-0_13
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Zhivotovsky,LA
中科院分区：
文献类型：
--
作者：
Zhivotovsky,LA
一个单倍体群体受到反复的有害突变和两种环境，提供两种不同的选择系数剖面的位点建模。种群应该居住在一个“家”环境中，在那里它进化出相应的遗传结构。然后，一代人口暴露在第二种“外国”环境中。平均种群适应度的下降被认为是外来环境对种群造成压力的一种度量。我将应力相对强度定义为1减去国内外环境中平均适应度之比，并给出相应的解析表达式。应力强度由三个不同的因素组成：应力的环境成分，它完全由外部环境的非遗传因素（其承载能力）决定，以及两个遗传成分。后者由外部环境对选择系数的直接影响引起的环境×遗传成分，以及由于种群对家乡环境的适应而引起的进化成分组成。其中，研究表明，即使内外环境相等，使应激的环境和环境×遗传成分都不存在，由于进化成分，应激仍然会在外环境中发生。该模型还预测，紧张的外部环境会导致适应度基因型方差的增加。本文还讨论了应激环境下种群变异的其他一些特征。从这个模型中可以得出的一般结论是，只有在考虑到给定的种群和种群进化的环境时，才能声称某个环境是有压力的。
A haploid population subject to recurrent deleterious mutations and two environments that provide two different profiles of selection coefficients over loci are modeled. The population is supposed to inhabit one “home” environment where it evolves the corresponding genetic constitution. One generation of the population is then exposed to the second, “foreign” environment. The decline in the mean population fitness is considered as a measure of stress in the population caused by the foreign environment. I define the relative strength of stress as 1 minus the ratio of the mean fitnesses in the foreign and home environments, and give the corresponding analytical expression. The stress strength is composed of three different contributors: the environmental component of stress, which is determined by purely external, non-genetic factors of the foreign environment (its carrying capacity), and two genetic components. The latter consists of the environment × genetic component, caused by the direct influence of the foreign environment on selection coefficients, and of the evolutionary component that is due to the adaptation of the population to the home environment. Among others, it is shown that even if the home and foreign environments were equivalent, so that both the environmental and environmental × genetic components of stress were absent, stress would still occur in the foreign environment due to the evolutionary component. The model also predicts that stressful foreign environments cause an increase in the genotypic variance of fitness. Some other features of population variability in stressful environments are discussed. A general conclusion that can be drawn from this model is that a certain environment may be claimed as stressful only if considered with respect to both a given population and the environment in which the population has evolved.
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影响因子：
6.7
作者：
J. Yoshimura;C. Clark
通讯作者：
C. Clark
空间异质环境中的健身模式和表型可塑性。
DOI：
10.1017/s0016672300034212
发表时间：
1996
期刊：
Genetical research
影响因子：
--
作者：
Zhivotovsky,LA;Feldman,MW;Bergman,A
通讯作者：
Bergman,A
影响因子：
3.3
作者：
A. Tantawy;G. S. Mallah
通讯作者：
G. S. Mallah
有害突变作为进化因素。
影响因子：
2
作者：
Alexey S. Kondrashov
通讯作者：
Alexey S. Kondrashov
DOI：
--
发表时间：
1946
期刊：
影响因子：
--
作者：
I. Schmalhausen
通讯作者：
I. Schmalhausen