Dissertation Research: Mechanics of Speciation in the Rock Dwelling Cichlid Genus Melanochromis in Lake Malawi, Africa (Teleostei:Cichlidae)

马拉维湖（非洲东部）的慈鲷（双鱼座：慈鲷科）动物群的物种多样性在其他脊椎动物谱系中是无与伦比的。马拉维湖估计有500种不同的物种，其中大多数只在这个湖中发现。据认为，这种高水平的生物多样性是在马拉维湖存在的相对较短的时间内产生的。许多研究人员认为，导致物种丰富的力量至今仍在发挥作用。其中一个模型，多米尼假说，认为极端的亲缘关系（大大减少种群之间的迁徙）和每个种群中独特的配偶识别系统的发展，导致了马拉维湖许多慈鲷物种的出现和维持。到目前为止，这一假设的测试很难设计和实施。在这项研究中，Jeffrey Markert在Thomas Kocher的指导下，将使用详细的实地抽样技术、实验室配偶选择实验和分子标记来评估Dominey假说的地理和行为成分。DNA指纹鉴定，结合对马拉维湖南昆巴半岛东岸慈鲷种群的精细调查，将评估这些种群的亲缘关系程度；据预测，这些鱼几乎不会离开家园。DNA指纹识别技术还将与实验室实验相结合，在实验室实验中，在一个与自然条件接近的圈养环境中饲养的鱼，被允许从多个种群中选择配偶；据预测，这些鱼会更喜欢自己种群中的成员。这项研究的结果将测试多米尼假说在马拉维湖鲷鱼物种多样性模型中的能力。这将有助于评估多米尼假说是否只适用于马拉维湖的鲷鱼物种多样性，还是可以更广泛地应用。

9623881 KOCHER The fauna of cichlid fish (Pisces: Cichlidae) in Lake Malawi (eastern Africa) represent a level of species diversity unparalleled in other vertebrate lineages. Lake Malawi contains an estimated 500 distinct species, most of which are found only in this lake. It is thought that this high level of biodiversity has been generated during the relatively short time that Lake Malawi has been in existence. Many researchers believe that the forces responsible for generating this species richness are still operating today. One model, the Dominey hypothesis, suggests that extreme philopatry (greatly reduced migration between populations) and the development of distinct mate recognition systems within each population, have resulted in the emergence and maintenance of the many Lake Malawi cichlid species. Until now, tests of this hypothesis have been difficult to design and implement. In this study, Jeffrey Markert, under the direction of Thomas Kocher, will use detailed field sampling techniques, laboratory mate-choice experiments, and molecular markers to evaluate the geographic and behavioral components of the Dominey hypothesis. DNA fingerprinting, combined with a fine scale survey of cichlid populations along the eastern shore of Lake MalawiOs Nankumba Peninsula, will assess the extent of philopatry in these populations; the prediction is that these fish hardly ever Oleave homeO. DNA fingerprinting will also be combined with laboratory experiments in which fish, raised in an enclosure that closely replicates natural conditions, are permitted to choose mates from multiple populations; the prediction is that the fish will prefer members of their own population. The results of this study will test the ability of the Dominey hypothesis to model species diversity in Lake Malawi cichlid fish. It will help assess whether the Dominey hypothesis applies only to species diversity in Lake Malawi cichlid fish or can be applied more generally.