Introgression in Pupfish: Role of Sexual & Natural Selection

项目编号：9806483 PI: Kodric-Brown， Astrid题目：“小鱼的基因渗入：性和自然选择的作用”。佩科斯小鱼原产于佩科斯河，由于与一种密切相关的引进物种羊头鲦鱼杂交，目前正处于灭绝的危险之中。在引进后的五年内，杂交品种在其历史范围的一半以上取代了本地物种。有几个因素可能有助于杂交种的成功；它们可能比亲本物种中的任何一个生存得更好，生长得更快，作为配偶也更有吸引力。雌性配偶选择的实验研究和两个亲本物种及其杂交种雄性之间的竞争互动将决定杂交种是否具有交配优势。生活史特征，如生长速度、成熟时的大小和产生的卵的数量，将被测量，以确定它们是否影响杂交率。许多西南本地鱼类由于与外来物种杂交而面临灭绝的威胁。本研究将提供有关促进与引进的非本地物种杂交的行为和生态过程的信息，以及这些过程在性选择和物种形成中的作用。本研究对本地物种种群的保护和恢复具有一定的应用价值。

Proposal Number: 9806483 PI: Kodric-Brown, Astrid Title: "Introgression in Pupfish: Role of Sexual and Natural Selection". The Pecos pupfish, native to the Pecos river, is curently in jeopardy of extinction due to hybridization with a closely related introduced species, the Sheepshead minnow. Within five years of the introduction, hybrids replaced the native species in over half of its istoric range. Several factors may contribute to the success of hybirds; they may survive better, grow faster, and be more attractive as mates than either of the parental species. Experimental studies of female mate choice and competitive interactions among males of the two parental species and their hybrids will determine whether hybrids have a mating advantage. Life-history traits, such as growth rate, size at maturity, and the number of eggs roduced, will be measured to determine whether they influence the rate of hybridization. Many native southwestern fishes are threatened by extinction through hybridization with introduced exotic species. This research will provide information about the behavioral and ecological processes that promote hybridization with introduced non-native species and more generally, the role of these processes in sexual selection and species formation. This research has applications for conservation and restoration of populations of native species.