Abstract：
As genomic-scale data sets become economically feasible for most organisms, a key question for conservation biology is whether the increased resolution offered by new genomic approaches justifies repeating earlier studies based on traditional markers, rather than investing those same time and monetary resources in less-known species. Genomic studies offer clear advantages when the objective is to identify adaptive loci that may be critical to conservation policy-makers. However, the answer is far less certain for the population and landscape studies based on neutral loci that dominate the conservation genetics research agenda. We used RADseq to revisit earlier molecular studies of the IUCN Critically Endangered Magdalena River turtle (Podocnemis lewyana), documenting the conservation insights gained by increasing the number of neutral markers by several orders of magnitude. Earlier research indicated that P. lewyana has the lowest genetic diversity known for any chelonian, and little or no population differentiation among independent rivers. In contrast, the RADseq data revealed discrete population structure with isolation-by-distance within river segments and identified precise population breaks clearly delineating management units. It also confirmed that the species does not have extremely low heterozygosity and that effective population sizes are probably sufficient to maintain long-term evolutionary potential. Contrary to earlier inferences from more limited population genetic markers, our genomic data suggest that management strategies should shift from active genetic rescue to more passive protection without extreme interventions. We conclude with a list of examples of conservation studies in other vertebrates indicating that for many systems a genomic update is worth the investment.
摘要：
由于基因组规模的数据集对大多数生物体而言在经济上是可行的，保护生物学的一个关键问题是，新基因组方法提供的分辨率增加是否证明重复基于传统标记的早期研究是合理的，而不是将同样的时间和金钱资源投资于鲜为人知的物种。当目标是确定对保护政策制定者至关重要的适应性基因座时，基因组研究提供了明显的优势。然而,对于基于中性基因座的人口和景观研究，答案远不确定，而中性基因座在保护遗传学研究议程中占主导地位。我们使用RADseq重新审视了IUCN极度濒危的马格达莱纳河龟（Podocnemislewyana）的早期分子研究，记录通过将中性标记的数量增加几个数量级而获得的保护见解。较早的研究表明，lewyana的遗传多样性最低，独立河流之间很少或没有人口差异。相比之下,RADseq数据揭示了离散的人口结构，在河段内按距离隔离，并确定了精确的人口中断，清楚地描绘了管理单位。它还证实了该物种没有极低的杂合性，并且有效的种群规模可能足以维持长期的进化潜力。与更有限的群体遗传标记的早期推论相反，我们的基因组数据表明,管理策略应该从主动遗传挽救转变为更被动的保护,而无需极端干预.最后，我们列出了其他脊椎动物的保护性研究示例，表明对于许多系统，基因组更新值得投资。
