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Abstract：
Linking genetic diversity to extinction is a common goal in genomic studies. Recently, a debate has arisen regarding the importance of genetic variation in conservation as some studies have failed to find associations between genome-wide genetic diversity and extinction risk. However, only rarely are genetic diversity and fitness measured together in the wild, and typically demographic history and environment are ignored. It is therefore difficult to infer whether a lack of an association is real or obscured by confounding factors. To address these shortcomings, we analyzed genetic data from 7,501 individuals with extinction data from 279 meadows and mortality of 1,742 larval nests in a butterfly metapopulation. We found a strong negative association between genetic diversity and extinction when considering only heterozygosity in models. However, this association disappeared when accounting for ecological covariates, suggesting a confounding between demography and genetics and a more complex role for heterozygosity in extinction risk. Modeling interactions between heterozygosity and demographic variables revealed that associations between extinction and heterozygosity were context-dependent. For example, extinction declined with increasing heterozygosity in large, but not currently small populations, although negative associations between heterozygosity, extinction, and mortality were detected in small populations with a recent history of decline. We conclude that low genetic diversity is an important predictor of extinction, predicting >25% increase in extinction beyond ecological factors in certain contexts. These results highlight that inferences about the importance of genetic diversity for population viability should not rely on genomic data alone but require investments in obtaining demographic and environmental data from natural populations.
摘要：
将遗传多样性与灭绝联系起来是基因组研究的共同目标。最近,由于一些研究未能发现全基因组遗传多样性与灭绝风险之间的关联，因此有关遗传变异在保护中的重要性的争论已经引起。然而,很少在野外一起测量遗传多样性和适应性，通常忽略人口统计历史和环境。因此，很难推断缺乏关联是真实的还是被混杂因素所掩盖。为了解决这些缺点，我们分析了来自7,501个个体的遗传数据，以及来自279个草甸的灭绝数据和蝴蝶种群中1,742个幼虫巢的死亡率。当仅考虑模型中的杂合性时，我们发现遗传多样性与灭绝之间存在很强的负相关。然而,当考虑生态协变量时，这种关联消失了，表明人口统计学和遗传学之间的混淆以及杂合性在灭绝风险中的更复杂作用。对杂合性和人口统计学变量之间的相互作用进行建模表明，灭绝和杂合性之间的关联取决于上下文。例如,灭绝随着杂合性的增加而下降，但目前人口不多，尽管杂合性之间存在负相关，灭绝,在最近有下降史的小人群中发现了死亡率。我们得出结论，低遗传多样性是灭绝的重要预测因素，预测在某些情况下，超过生态因素的灭绝增加>25%。这些结果突出表明，关于遗传多样性对种群生存能力的重要性的推论不应仅仅依靠基因组数据，而需要投资从自然种群中获得人口和环境数据。
