German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Puschstrasse 4, 04103, Leipzig, Germany.
University of Leipzig, Ritterstrasse 26, 04109, Leipzig, Germany.
Heredity (Edinb). 2024 Oct;133(4):249-261. doi: 10.1038/s41437-024-00710-4. Epub 2024 Sep 2.
Anthropogenic habitat modification and climate change are fundamental drivers of biodiversity declines, reducing the evolutionary potential of species, particularly at their distributional limits. Supportive breeding or reintroductions of individuals are often made to replenish declining populations, sometimes informed by genetic analysis. However, most approaches utilised (i.e. single locus markers) do not have the resolution to account for local adaptation to environmental conditions, a crucial aspect to consider when selecting donor and recipient populations. Here, we incorporate genetic (microsatellite) and genome-wide SNP (ddRAD-seq) markers, accounting for both neutral and putative adaptive genetic diversity, to inform the conservation management of the threatened common midwife toad, Alytes obstetricans at the northern and eastern edges of its range in Europe. We find geographically structured populations (n = 4), weak genetic differentiation and fairly consistent levels of genetic diversity across localities (observed heterozygosity and allelic richness). Categorising individuals based on putatively adaptive regions of the genome showed that the majority of localities are not strongly locally adapted. However, several localities present high numbers of private alleles in tandem with local adaptation to warmer conditions and rough topography. Combining genetic diversity and local adaptations with estimates of migration rates, we develop a decision-making framework for selecting donor and recipient populations which maximises the geographic dispersal of neutral and putatively adaptive genetic diversity. Our framework is generally applicable to any species, but especially to amphibians, so armed with this information, conservationists may avoid the reintroduction of unsuitable/maladapted individuals to new sites and increase the evolutionary potential of populations within species.
人为的栖息地改变和气候变化是生物多样性减少的根本驱动因素，降低了物种的进化潜力，尤其是在它们的分布极限处。为了补充数量下降的种群，人们经常进行支持性繁殖或重新引入个体，有时还会进行遗传分析。然而，大多数使用的方法（即单一位点标记）没有分辨率来解释对环境条件的局部适应，这是在选择供体和受体种群时需要考虑的关键方面。在这里，我们结合遗传（微卫星）和全基因组 SNP（ddRAD-seq）标记，同时考虑中性和假定的适应性遗传多样性，为欧洲北部和东部范围内受威胁的普通蟾蜍 Alytes obstetricans 的保护管理提供信息。我们发现存在地理结构的种群（n=4）、较弱的遗传分化和相当一致的遗传多样性水平（观察到的杂合度和等位基因丰富度）。根据基因组中假定的适应性区域对个体进行分类表明，大多数地点并没有强烈的局部适应性。然而，有几个地点存在大量的私有等位基因，同时适应较温暖的条件和崎岖的地形。我们将遗传多样性和局部适应性与迁移率估计值结合起来，制定了一个选择供体和受体种群的决策框架，该框架最大限度地分散中性和假定的适应性遗传多样性。我们的框架通常适用于任何物种，但特别是两栖动物，因此，有了这些信息，保护主义者可以避免将不适合/适应不良的个体重新引入新地点，并增加物种内种群的进化潜力。
