Evolution of Reproductive Isolation and Speciation in Neurospora

这项研究的目的是了解当种群分化成不同的物种时，杂交的障碍是如何演变的。这一问题将通过研究粗糙脉孢菌（一种丝状真菌（霉菌），是生物学中研究得最好的生物体之一）的两个地理和遗传隔离种群之间的杂交来解决。crassa及其近缘种N.中间的该项目有两个主要目标。第一个是确定和测量生殖隔离的各个组成部分，在整个性途径，从杂交父母之间的交配相互作用的缺陷，杂种后代的活力。第二个目标是绘制控制生殖隔离障碍的遗传位点，并在不同地理环境下检验生殖隔离的进化遗传学假设。生殖隔离的进化是新物种起源的关键事件，希望这项研究将增加我们对促进地球生物多样性的基本机制的了解。 在脉孢菌中，与许多物种一样，生殖隔离的强度是地理结构性的：对于给定的物种对，来自不同位置的杂交亲本比来自相同位置的杂交亲本更能相互作用。这一观察结果表明，基线生殖隔离地理隔离物种之间的进化是加强自然选择对杂交时，物种一起发生。 在这里进行的工作旨在了解这一过程的遗传基础。

The object of the research is to understand how barriers to hybridization evolve as populations diverge into separate species. This problem will be addressed by studying hybrid crosses between two geographically and genetically isolated populations of Neurospora crassa, a filamentous fungus (mold) that is one of the best studied organisms in biology, and between N. crassa and its close relative N. intermedia. This project has two main goals. The first is to identify and measure the individual components of reproductive isolation operating throughout the sexual pathway, from defects in mating interactions between hybridizing parents to inviability of hybrid offspring. The second goal is to map genetic loci controlling reproductive isolation barriers and to test hypotheses about the evolutionary genetics of reproductive isolation under different biogeographic scenarios. The evolution of reproductive isolation is a key event in the origin of new species, and it is hoped that this research will add to our scant understanding of a foundational mechanism that promotes biodiversity on Earth. In Neurospora, as in many species, the intensity of reproductive isolation is geographically structured: for a given species pair, hybridizing parents from disparate locations are more interfertile than hybridizing parents from the same location. This observation suggests that baseline reproductive isolation evolving between geographically isolated species is reinforced by natural selection against hybridization when species occur together. The work undertaken here aims to understand the genetic basis of this process.