Data from: Tackling intraspecific genetic structure in distribution models better reflects species geographical range

Genetic diversity provides insight into heterogeneous demographic and adaptive history across organisms’ distribution ranges. For this reason, decomposing single species into genetic units may represent a powerful tool to better understand biogeographical patterns as well as improve predictions of the effects of GCC (global climate change) on biodiversity loss. Using 279 georeferenced Iberian accessions, we used classes of three intraspecific genetic units of the annual plant Arabidopsis thaliana obtained from the genetic analyses of nuclear SNPs (single nucleotide polymorphisms), chloroplast SNPs, and the vernalization requirement for flowering. We used SDM (species distribution models), including climate, vegetation, and soil data, at the whole-species and genetic-unit levels. We compared model outputs for present environmental conditions and with a particularly severe GCC scenario. SDM accuracy was high for genetic units with smaller distribution ranges. Kernel density plots identified the environmental variables underpinning potential distribution ranges of genetic units. Combinations of environmental variables accounted for potential distribution ranges of genetic units, which shrank dramatically with GCC at almost all levels. Only two genetic clusters increased their potential distribution ranges with GCC. The application of SDM to intraspecific genetic units provides a detailed picture on the biogeographical patterns of distinct genetic groups based on different genetic criteria. Our approach also allowed us to pinpoint the genetic changes, in terms of genetic background and physiological requirements for flowering, that Iberian A. thaliana may experience with a GCC scenario applying SDM to intraspecific genetic units.

遗传多样性可揭示物种分布范围内异质的种群动态与适应性历史。据此，将单一物种划分为遗传单元，或可成为深入解析生物地理格局、提升全球气候变化（Global Climate Change, GCC）对生物多样性丧失影响预测精度的有力研究手段。本研究以279份带有地理坐标的伊比利亚半岛种质为材料，通过核单核苷酸多态性（single nucleotide polymorphisms, SNPs）、叶绿体单核苷酸多态性以及开花春化需求的遗传分析，鉴定得到一年生植物拟南芥（Arabidopsis thaliana）的3个种内遗传单元类群。本研究在物种整体与遗传单元两个层面，采用包含气候、植被与土壤数据的物种分布模型（Species Distribution Models, SDM），并对比了当前环境条件与极端严重全球气候变化情景下的模型输出结果。结果显示，对于分布范围较小的遗传单元，物种分布模型的预测精度较高；核密度图明确了支撑遗传单元潜在分布范围的核心环境变量。环境变量的组合共同决定了遗传单元的潜在分布范围，在几乎所有遗传单元中，其潜在分布范围均随全球气候变化发生显著收缩，仅有2个遗传簇的潜在分布范围随全球气候变化有所扩张。将物种分布模型应用于种内遗传单元，可基于不同遗传标准为不同遗传类群的生物地理格局提供精细的解析。本研究方法还可通过将物种分布模型应用于种内遗传单元，精准揭示伊比利亚半岛拟南芥在全球气候变化情景下可能发生的、与遗传背景及开花生理需求相关的遗传变化。