Data from: Warm–cold colonization: response of oaks to uplift of the Himalaya–Hengduan Mountains

Clarifying the relationship between distribution patterns of organisms and geological events is critical to understanding the impact of environmental changes on organismal evolution. Quercus sect. Heterobalanus is now distributed across the Himalaya–Hengduan Mountains (HHM) and warm lowland in East China, yet how the distribution patterns of this group changed in response to the HHM uplift remains largely unknown. This study examines the effect of tectonic events in the HHM region on the oaks, providing a biological perspective on the geological history of this region. Fifty-six populations of Quercus sect. Heterobalanus were genotyped using four cpDNA regions and nine nSSR loci to assess population structure and diversity, supplemented by molecular dating and ancestral area reconstructions. The underlying demographic dynamics were compared using ecological niche models of the species distributions during the Last Glacial Maximum and the present. These analyses illustrate that Quercus sect. Heterobalanus diversified as the HHM uplifted and climatic cooling during the mid-Miocene, colonizing the cold habitats from warm broadleaf mixed forests. Lineages in cold highlands and warm lowlands have diverged as a consequence of local adaptation to diverging climates since the late Miocene. Our results suggest that continuous uplift of the HHM in the late Miocene to early Pliocene accompanied by simultaneous cooling, triggered the differentiation of oaks. The biogeography of Quercus sect. Heterobalanus illuminates that the geological events responsible for the modern-day HHM.

阐明生物分布格局与地质事件之间的关联，对于理解环境变化对生物演化的影响具有关键意义。当前，栎属（Quercus）异形栎组（Heterobalanus）的分布范围覆盖喜马拉雅-横断山脉（HHM）与中国东部温暖低地，但该类群的分布格局如何响应喜马拉雅-横断山脉的抬升而发生演变，目前仍不甚明晰。本研究探讨了喜马拉雅-横断山脉区域的构造事件对该类栎树的影响，为该区域的地质历史提供了生物学视角。研究人员通过4个叶绿体DNA（cpDNA）片段与9个核简单序列重复（nSSR）位点，对56个栎属异形栎组种群开展基因分型，以解析其种群结构与遗传多样性，并辅以分子定年与祖先区域重建分析。结合末次冰盛期（Last Glacial Maximum）与当前的物种分布生态位模型，对其潜在的种群动态历史进行了对比分析。上述分析结果显示，随着喜马拉雅-横断山脉的抬升以及中新世中期的气候变冷，栎属异形栎组发生了物种分化，并从温暖的阔叶混交林拓殖至寒冷生境。自中新世晚期以来，栖息于寒冷高海拔区域与温暖低海拔区域的谱系，因适应分异的气候而产生了分化。本研究结果表明，中新世晚期至上新世早期喜马拉雅-横断山脉的持续抬升，伴随同期的气候变冷，触发了该类栎树的谱系分化。栎属异形栎组的生物地理学研究结果，阐明了造就现代喜马拉雅-横断山脉格局的地质事件。