OPUS: CRS: Through the looking glass: host-parasite coevolution and genetic recombination

当我们环顾四周时，一般来说，既有雄性又有雌性的物种是普遍规律。然而，男性和女性的持续存在以及涉及基因重组的生殖是生物学中的一个经典问题。这个问题源于男性不生育的基本事实。因此，通过简单地复制成年女性（克隆）进行繁殖的全女性谱系预计将产生两倍于既有男性又有女性的群体的后代。这种繁殖方式会导致克隆形式在种群中迅速传播。但是，尽管有这种繁殖优势，无性繁殖是罕见的。这一悖论可以追溯到查尔斯·达尔文，关于基因重组的优势，人们提出了几十种假设。其中一个主要的假设是红皇后，它假设重组的后代通常更受青睐，因为基因多样化的后代更有可能逃脱快速进化的寄生虫。这个项目的目标是综合三十多年来对红皇后假说的研究。该合成将作为一本针对生物学高级本科生和研究生的书出版，将引起公众的兴趣。该项目还包括对中学教师的培训，以及继续开发纸牌游戏，向高中生和大学生传授进化论。这项工作的模式生物是新西兰淡水蜗牛（Potamopyrgus antipodarum），其中产生重组后代的雌性和只产生克隆后代的雌性共存。这本书将综合长期的实地观察和短期的实验，旨在确定生产基因可变的交叉受精后代的成本和收益。这本书还将综合对红皇后假说的理论研究；它将涵盖进化生物学中的一些关键概念，比如硬选择与软选择，频率依赖选择，下注对冲，突变积累，稳定平衡与振荡动力学，以及配偶选择。这本书还阐述了传染病的生态学和遗传学的基本原理。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

As we look around us, species with both males and females are the general rule. Yet, the persistence of males and females along with reproduction that involves genetic recombination, is a classic problem in biology. The problem stems from the basic fact that males do not give birth. Thus, an all-female lineage that reproduces by simply replicating the adult female (cloning) would be expected to produce twice as many offspring as a population with both males and females. This mode of reproduction should lead to the very rapid spread of the clonal form in populations. But, in spite of this reproductive advantage, clonal reproduction is rare. This paradox dates back to Charles Darwin, and dozens of hypotheses for the advantages of genetic recombination have been put forward. One of the leading hypotheses is the Red Queen, which posits that recombining offspring are favored, on average, because genetically diverse offspring would be more likely to escape rapidly evolving parasites. The goal of this project is to synthesize more than thirty years of work on the Red Queen hypothesis. The synthesis would be published as a book targeting advanced undergraduates and graduate students in biology, would be of interest to the general public. The project also involves the training of secondary school teachers and the continued development of card games to teach high school and college students about evolution.The model organism for this work is a New Zealand freshwater snail (Potamopyrgus antipodarum) in which females that produced recombined offspring and those that only produce clonal offspring coexist. The book would synthesize long-term field observations along with shorter term experiments designed to determine the cost and benefits of producing genetically variable, cross-fertilized offspring. The book would also synthesize theoretical studies of the Red Queen hypothesis; and it would cover some of the key concepts in evolutionary biology, such as hard versus soft selection, frequency-dependent selection, bet-hedging, mutation accumulation, stable equilibria versus oscillatory dynamics, and mate choice. The book would also lay out the fundamentals regarding the ecology and genetics of infectious disease.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.