NEW APPROACHES TO THE MODELING OF SPECIATION

这个项目的总体目标是更好地理解生物学 通过动态和静态研究导致物种形成的过程 各种多位点模型的行为。现有的建模方法 物种形成在几个方面都是不足的。通常是一小部分(1个 或两个)的基因座或数量性状，假设为选择素 弱，人口规模被认为是恒定的，只有非常 数量有限的遴选制度大多反映了主导 对“崎岖适应性景观”范式进行了研究。最近被砍了一刀 “洞穴适应性景观”的比喻(Gavrilets和Gravner，1997) 是作为传统观点的一种可信的替代方案提出的 崎岖的适应性景观。这个比喻，可以追溯到两个- Dobzhansky(1937)提出的座位双等位基因模型是该模型的核心 这里提出了一项研究。 使用分析方法和广泛的数值方法相结合 模拟本项目将研究孔洞物种形成的动力学。 考虑各种因素的适应性景观 自然种群。在开发和分析物种形成模型时 标准群体遗传学方法和最近的新方法 将使用在物理学中发展起来的。 该项目将调查洞穴适应性景观的结构。 通过关注相关的景观和专注于 基因分化和物种形成的可能性由 重组。基于洞穴适应的种群进化动态 由突变、分离和重组决定的景观， 随机和非随机交配、空间分布、种群增长和 将对随机漂移进行研究。理论假设和预测将 根据自然种群和实验室种群的特性进行测试。为 为了达到这个目的，杂交和回交的适合度分布， 实验室种群对人工选择的反应， 杂交区的特征和宏观进化模式 将使用化石记录中的数据。

The overall aim of this project is to better understand biological processes leading to speciation through a study of the dynamic and static behavior of various multilocus models. Existing approaches to the modeling of speciation are deficient in several ways. Usually a small number (one or two) of loci or quantitative traits are considered, selectin is assumed to be weak, population size is considered to be constant, and only a very limited number of selection regimes mostly reflecting the dominant paradigm of "rugged adaptive landscapes" have been studied. Recently a hew metaphor of "holey adaptive landscapes" (Gavrilets and Gravner, 1997) has been put forward as a plausible alternative to the conventional view of rugged adaptive landscapes. This metaphor, which can be traced to a two- locus two-allele model described by Dobzhansky (1937), is the core of the research proposed here. Using a combination of analytical methods and extensive numerical simulations this project will study the dynamics of speciation of holey adaptive landscapes taking into account various factors operating in natural populations. In developing and analyzing speciation models both standard population genetics approaches and novel methods recently developed in physics will be used. This project will investigate the structure of holey adaptive landscapes by focusing on correlated landscapes and concentrating on the possibilities for genetic divergence and speciation introduced by recombination. The dynamics of population evolution on holey adaptive landscapes as determined by mutation, segregation and recombination, random and non-random mating, spatial distribution, population growth and random drift will be studied. Theoretical assumptions and predictions will be tested against properties of natural and laboratory populations. For this purpose, distributions of fitnesses in hybrids and backcrosses, responses of laboratory populations to artificial selection, characteristics of hybrid zones, and macroevolutionary patterns deduced from the fossil record will be used.