| 描述信息 |
Rivers have intrigued researchers for centuries due to the most diverse, dynamic, and productive ecosystems on earth. Yet, mechanism of plant diversification driven by river systems remains largely unknown. Debregeasia orientalis, an endemic species to East Asia, and distributing along water flow, provided powerful study system to address this issue. In this study, we generated a chromosome-scale de novo genome assembly of D. orientalis, and produced whole-genome sequences from 332 accessions, then integrate population genomic techniques with ecological analysis, we found that three groups should be considered within D. orientalis, and they distributed along three distinguished river systems, supporting riverine landscape affects species differentiation; Furthermore, we revealed that the Pleistocene climate changes drove lineage diversification isolated in micro-refugia, indicating that climate changes trigger complex ecological responses in river ecosystems. Additionally, we uncovered that D. orientalis has different ecological niches in different river systems, and the key ecological factors determining these niches are identified, suggesting different selective pressures were produced to plants along the different rivers. Overall, morphodynamics vary and climate change produced various ecological habitats for different rivers, under different selective pressures, same species started to differentiate among different river systems, combining with effect of climate change, which formed different species over long time, eventually resulting in the extremely high biodiversity of river systems on Earth. This study expands our understanding of mechanism of plant diversification driven by river systems by the largest genomic data of plant to date, and contributes to a growing body of knowledge on the relationships between plant and river that will facilitate continued efforts including the formation of biodiversity on Earth. |
