The competition between simple and complex evolutionary trajectories in asexual populations.
The competition between simple and complex evolutionary trajectories in asexual populations.
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DOI：
10.1186/s12862-015-0334-0
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发表时间：
2015-03-26
影响因子：
3.4
通讯作者：
Desai MM
中科院分区：
文献类型：
--
作者：
Ochs IE;Desai MM
在崎岖的适应性景观中，符号上位性是常见的，适应通常涉及个体有益的“上坡”突变或涉及适应性山谷或高原的更复杂的突变轨迹。进化过程的动力学决定了进化将在各种竞争的可能轨迹中选择任何特定路径的概率。如果我们要理解崎岖地貌上适应的结果和可预测性，理解这种进化选择是必不可少的。我们提出了一个简单的模型来分析进化将避开立即上坡的路径，有利于跨越健身谷或高原，导致更高的健身，但不太容易获得的基因型的概率。我们计算这种概率如何取决于人口规模，突变率和相关的选择压力，并比较我们的分析结果赖特-费舍尔模拟。我们发现，跨越山谷的概率依赖于非单调的人口规模：中等规模的人口最有可能遵循“贪婪”的策略，立即获得有益的突变，即使他们导致进化的死胡同，而较大和较小的人口更有可能跨越健身谷，以达到遥远的有利基因型。我们明确地确定这些不同的制度之间的界限，在相关的进化参数。超过一定的阈值人口规模，我们表明，人口发现更遥远的峰值的概率仅取决于一个简单的相关参数的组合。
On rugged fitness landscapes where sign epistasis is common, adaptation can often involve either individually beneficial “uphill” mutations or more complex mutational trajectories involving fitness valleys or plateaus. The dynamics of the evolutionary process determine the probability that evolution will take any specific path among a variety of competing possible trajectories. Understanding this evolutionary choice is essential if we are to understand the outcomes and predictability of adaptation on rugged landscapes. We present a simple model to analyze the probability that evolution will eschew immediately uphill paths in favor of crossing fitness valleys or plateaus that lead to higher fitness but less accessible genotypes. We calculate how this probability depends on the population size, mutation rates, and relevant selection pressures, and compare our analytical results to Wright-Fisher simulations. We find that the probability of valley crossing depends nonmonotonically on population size: intermediate size populations are most likely to follow a “greedy” strategy of acquiring immediately beneficial mutations even if they lead to evolutionary dead ends, while larger and smaller populations are more likely to cross fitness valleys to reach distant advantageous genotypes. We explicitly identify the boundaries between these different regimes in terms of the relevant evolutionary parameters. Above a certain threshold population size, we show that the probability that the population finds the more distant peak depends only on a single simple combination of the relevant parameters.
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影响因子：
4.5
作者：
Salverda ML;Dellus E;Gorter FA;Debets AJ;van der Oost J;Hoekstra RF;Tawfik DS;de Visser JA
通讯作者：
de Visser JA
DOI：
10.1073/pnas.1213613110
发表时间：
2013-01-08
影响因子：
11.1
作者：
Szendro, Ivan G.;Franke, Jasper;Krug, Joachim
通讯作者：
Krug, Joachim
影响因子：
3.3
作者：
Weissman, Daniel B.;Feldman, Marcus W.;Fisher, Daniel S.
通讯作者：
Fisher, Daniel S.
影响因子：
64.8
作者：
Poelwijk, Frank J.;Kiviet, Daniel J.;Tans, Sander J.
通讯作者：
Tans, Sander J.
影响因子：
2.9
作者：
Dawid, Alexandre;Kiviet, Daniel J.;Tans, Sander J.
通讯作者：
Tans, Sander J.