The Speed of Adaptation in Large Asexual Populations
The Speed of Adaptation in Large Asexual Populations
复制标题
大量无性种群的适应速度
作者：
C. Wilke
在大型无性种群中，有益的突变必须相互竞争才能固定下来。在这里，我推导了在种群规模N较大，新的有益突变的平均效应小于新的有害突变的平均效应，并且新的有益突变呈指数分布的假设下，固定突变的替代率和平均有益效应的显式解析表达式。随着N的增加，替代率接近于一个常数，等于新的有益突变的平均效应。固定突变的平均效应继续随着N呈对数增长。适应的速度，以对数适应度随时间的变化来衡量，对于中等大的N，它也随着N呈对数增长，对于极大的N，它呈双对数增长。此外，我推导了一个简单的公式，可以确定在给定N时，有益突变是相互竞争还是独立固定。最后，用数值模拟验证了所有结果。
In large asexual populations, beneficial mutations have to compete with each other for fixation. Here, I derive explicit analytic expressions for the rate of substitution and the mean beneficial effect of fixed mutations, under the assumptions that the population size N is large, that the mean effect of new beneficial mutations is smaller than the mean effect of new deleterious mutations, and that new beneficial mutations are exponentially distributed. As N increases, the rate of substitution approaches a constant, which is equal to the mean effect of new beneficial mutations. The mean effect of fixed mutations continues to grow logarithmically with N. The speed of adaptation, measured as the change of log fitness over time, also grows logarithmically with N for moderately large N, and it grows double-logarithmically for extremely large N. Moreover, I derive a simple formula that determines whether at given N beneficial mutations are expected to compete with each other or go to fixation independently. Finally, I verify all results with numerical simulations.
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DOI：
10.1073/pnas.92.13.5841
发表时间：
1995-06-20
影响因子：
11.1
作者：
NOVELLA, IS;DUARTE, EA;HOLLAND, JJ
通讯作者：
HOLLAND, JJ
影响因子：
3.3
作者：
H. Orr;Y. Kim
通讯作者：
H. Orr;Y. Kim
影响因子：
3.3
作者：
S. Otto;Corbin D. Jones
通讯作者：
S. Otto;Corbin D. Jones
无性动物的适应率。
影响因子：
3.3
作者：
Orr,HA
通讯作者：
Orr,HA
二倍体会增加适应率吗？
影响因子：
3.3
作者：
Orr,HA;Otto,SP
通讯作者：
Otto,SP