Hybrid zones among Palearctic amphibian lineages as a model to understand temporal patterns of species formation and refine methods of species delimitation

古北区两栖动物谱系的杂交带作为了解物种形成时间模式和完善物种界定方法的模型

• 批准号: 447016541
• 负责人: Professor Dr. Miguel Vences
• 金额: --
• 依托单位: Zoologisches Institut
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/447016541?language=en
• 关键词: Hybrid; zones; among; Palearctic; amphibian

Assessing reproductive isolation between lineages from the extent of admixture across their natural hybrid zones is an empirical and informative approach to delimit species, and allows unparalleled insights into the buildup of reproductive isolation over time, or with increasing genomic divergence. We propose to study hybrid zones of pairs of lineages of Palearctic amphibians; an existing data set will be complemented by analysis of 15 lineage pairs of the Eastern Palearctic using nuclear loci derived from RADseq. As a second work package, we will estimate a time-calibrated phylogenetic tree of 300 amphibian species-level lineages, including about 50 lineage pairs for which hybrid zone information is available. We predict the steepness of the hybrid zone cline and the width of the transition will scale with time, and with the accumulation of barrier loci. We will empirically test predictions from population genomic theory according to which reproductive isolation increases in a fast, non-linear fashion after the origin of a certain number of barrier loci. Our data set will furthermore allow us to test which factor better predicts reproductive isolation: divergence time or genomic divergence between two lineages. Finally, we will use downsampling procedures to understand how many RAD loci are needed for roughly but reliably estimating hybrid zone width, and informed by these results, will explore the prospects of an cost-effective multiplex PCR approach to amplify and sequence a set of 20-50 universal nuclear markers for next-generation DNA barcoding of amphibians; by applying this novel approach to the same samples studied by RADseq, we will assess its potential for initial assessments of hybrid zones patterns, and for species delimitation in general.

从其自然杂种区的混合范围内评估谱系之间的生殖隔离是一种经验和信息性的划界物种的方法，并且可以随着时间的流逝或增加基因组差异的生殖隔离构建而无与伦比的见解。我们建议研究果皮两栖动物谱系对的混合区。现有的数据集将通过对15个谱系对的核心基因座的分析来补充。作为第二个工作包，我们将估计一个有300个两栖动物物种水平谱系的时间校准的系统发育树，其中包括约50个谱系对，可为其中提供混合区域信息。我们预测杂交区基座的陡度和过渡的宽度将随着时间的流逝而扩展，并且随着屏障基因座的积累。我们将根据人口基因组理论的经验检验预测，根据该理论，在一定数量的屏障基因座的起源之后，生殖隔离以快速的非线性方式增加。我们的数据集将使我们能够测试哪个因素更好地预测生殖隔离：两个谱系之间的分歧时间或基因组差异。最后，我们将使用下采样程序来了解大致但可靠地估算混合区域宽度需要多少个RAD基因座，并在这些结果中得出信息，将探索一种具有成本效益的多重PCR方法的前景，以放大和序列的20-50个通用核标记，以示为20-50个通用核标记，以使下一代DNA DNA dna Barcoding of-Amphibians的DNA Barcoding;通过将这种新颖的方法应用于RadSeq研究的相同样品，我们将评估其对杂交区域模式的初步评估的潜力，以及一般的物种划界。