Clonal interference and Mullerʼs ratchet in spatial habitats
Clonal interference and Mullerʼs ratchet in spatial habitats
复制标题
空间栖息地中的克隆干扰和穆勒棘轮
作者：
Jakub Otwinowski;J. Krug
在空间种群中，独立产生的有益突变之间的竞争由于克隆的线性增长而不是指数增长而增强。最近的理论研究指出，由此产生的适应度动力学类似于表面生长过程，其中新层随机成核和扩散，导致尺度不变粗糙度的建立。这种情况与适应的标准观点有质的不同，因为适应的速度与种群大小无关，而适应度方差则与之无关。在这里，我们利用对地表生长过程的理解的最新进展来获得一维栖息地适应度分布的普遍非高斯形状的精确预测，并通过模拟验证了这一点。当突变是有害的而不是有益的，这个问题就变成了穆勒棘轮的空间版本。与混合良好的种群相比，即使在无限栖息地的极限下，如果比值为U / s 2 ？有害突变率与（负）选择系数的平方之间的>足够大。再次使用表面生长模型的类比，我们表明棘轮的静止和运动状态之间的过渡是由定向渗透控制的。
Competition between independently arising beneficial mutations is enhanced in spatial populations due to the linear rather than exponential growth of clones. Recent theoretical studies have pointed out that the resulting fitness dynamics is analogous to a surface growth process, where new layers nucleate and spread stochastically, leading to the build up of scale-invariant roughness. This scenario differs qualitatively from the standard view of adaptation in that the speed of adaptation becomes independent of population size while the fitness variance does not. Here we exploit recent progress in the understanding of surface growth processes to obtain precise predictions for the universal, non-Gaussian shape of the fitness distribution for one-dimensional habitats, which are verified by simulations. When the mutations are deleterious rather than beneficial the problem becomes a spatial version of Mullerʼs ratchet. In contrast to the case of well-mixed populations, the rate of fitness decline remains finite even in the limit of an infinite habitat, provided the ratio U d / s 2 ?> between the deleterious mutation rate and the square of the (negative) selection coefficient is sufficiently large. Using, again, an analogy to surface growth models we show that the transition between the stationary and the moving state of the ratchet is governed by directed percolation.
有性和无性的适应率：费雪穆勒效应的可解模型
影响因子：
3.3
作者：
Su-Chan Park;Joachim Krug
通讯作者：
Joachim Krug
相互竞争的岛屿限制了结构性人口的适应速度
影响因子：
1.4
作者：
Pokalyuk;L. Mathew;D. Metzler;P. Pfaffelhuber
通讯作者：
P. Pfaffelhuber
影响因子：
1.4
作者：
Rouzine, Igor M.;Brunet, Eric;Wilke, Claus O.
通讯作者：
Wilke, Claus O.