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arXiv math/0511743math.PRq-bio.PE
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最近的共同祖先在一个进化中的聚结过程

The process of most recent common ancestors in an evolving coalescent

P. Pfaffelhuber, A. Wakolbinger

摘要:

考虑一个通过可交换的繁殖动力学进化的单倍体种群,其中所有在时间$t$存活的个体都有一个最近的共同祖先(MRCA),他们生活在时间$A_t$。随着时间的推移,不仅人口会发生变化,而且其谱系也会发生变化:一些家庭将从人口中消失,最终将建立新的MRCA。对于一个时间平稳的情况下,并在无穷总体规模$N$与时间测量的$N$代,即在缩放的人口遗传学,导致费舍尔-赖特扩散和金曼的合并,我们研究的过程$\mathcal A = (A_t)$的跳跃形成的点过程的时间对$(E,B)$时,新的MRCA建立,当他们住。通过将这些粒子对表示为粒子的进入和离开时间,这些粒子的轨迹嵌入Donnelly和Kurtz(1999)的俯视图中,我们可以通过交换论证来证明泊松过程的时间$E$和时间$B$。此外,粒子表示有助于计算MRCA过程的各种特征,例如建立新MRCA时聚结的分布,以及今天过去的MRCA数量的分布。

英文摘要:

Consider a haploid population which has evolved through an exchangeable reproduction dynamics, and in which all individuals alive at time $t$ have a most recent common ancestor (MRCA) who lived at time $A_t$, say. As time goes on, not only the population but also its genealogy evolves: some families will get lost from the population and eventually a new MRCA will be established. For a time-stationary situation and in the limit of infinite population size $N$ with time measured in $N$ generations, i.e. in the scaling of population genetics which leads to Fisher-Wright diffusions and Kingman's coalescent, we study the process $\mathcal A = (A_t)$ whose jumps form the point process of time pairs $(E,B)$ when new MRCAs are established and when they lived. By representing these pairs as the entrance and exit time of particles whose trajectories are embedded in the look-down graph of Donnelly and Kurtz (1999) we can show by exchangeability arguments that the times $E$ as well as the times $B$ from a Poisson process. Furthermore, the particle representation helps to compute various features of the MRCA process, such as the distribution of the coalescent at the instant when a new MRCA is established, and the distribution of the number of MRCAs to come that live in today's past.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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