Determining the necessity and mechanisms of assortative mating in an adaptively diverging salamander population (Salamandra salamandra)

分类交配--优先选择与自己的类型交配--是适应性物种形成概念中的一个中心主题，因为这是防止不同适应类型之间的基因流动所必需的。最近对德国(波恩附近的Kottenforst)陆生火蜥蜴(Salamandra Salamandra)种群的研究表明，在同域条件下，对小森林内不同繁殖生境的适应启动了一个适应分化的过程。这一建议旨在分析在这一系统中进行分类交配的机制和必要性。我们将研究在半自然条件下的分类交配程度，以寻找现有的隔离机制。由于气味线索被火蜥蜴广泛用于种内交流和性别识别，我们将在基于行为/遗传的配偶选择实验中分析气味线索是否与栖息地相关的分类交配有关。此外，我们将应用生物测定方法和高效液相色谱-质谱仪相结合的方法，对涉及的气味物质进行化学分析和鉴定。为了在自然环境中关联和解释分类交配分析的结果，我们将通过分析几年来Kottenforst成虫的散布、栖息地大小和运动模式来确定适应类型的共生程度。这项详细的研究是分析在自然环境中适应性分化的陆生脊椎动物物种的分类交配机制的杰出方法。

Assortative mating – preferred mating with the own type - is a central theme within the concept of adaptive speciation, as it is required to prevent geneflow between differentially adapted types. Recent studies on a population of the terrestrial fire salamander (Salamandra salamandra) in Germany (the Kottenforst near Bonn) suggest that the adaptation to different reproduction habitats within the small forest initiated a process of adaptive divergence under sympatric conditions. This proposal is aimed to analyse the mechanisms and necessity of assortative mating in this system. We will investigate the degree of assortative mating under seminatural condition, in order to find existing isolation mechanisms. As odour cues are widely used by salamanders for intraspecific communication and sexual recognition, we will analyse in behavioural/genetic based mate-choice experiments whether odour cues are involved in habitat dependent assortative mating. Further, by applying a bioassay approach in combination with high performance liquid chromatography linked with mass spectrometry (HPLC/MS) we are going to analyse and identify involved odour substances chemically. In order to correlate and interpret the results from the assortative mating analysis in a natural context we will determine the degree of sympatry of adaptive types by analysing dispersal, home range size and movement patterns of adult individuals across the Kottenforst over several years. This detailed study is an outstanding approach to analyse mechanisms of assortative mating in a natural setting of an adaptively diverging terrestrial vertebrate species.