Massatti Rob, Faske Trevor M, Barnes Ivana M, Leger Elizabeth A, Parchman Thomas L, Richardson Bryce A, Knowles L Lacey
United States Geological Survey, Southwest Biological Science Center, Flagstaff, AZ 86001.
Department of Ecology and Evolutionary Biology, Museum of Zoology, University of Michigan, Ann Arbor, MI 48104.
Proc Natl Acad Sci U S A. 2025 Aug 5;122(31):e2410941122. doi: 10.1073/pnas.2410941122. Epub 2025 Jul 28.
Many widespread plant taxa of western North America have diversified into phenotypically and genetically divergent lineages due to complex biogeographic histories across heterogeneous landscapes. Mosaic hybrid zones can form when geographically co-occurring, yet environmentally distinct, lineages cross-pollinate and form hybrids that occupy unique environmental niches absent of a geographic cline. This expands the total environmental space across which parental and hybrid individuals grow, resulting in larger, less fragmented geographic distributions. Here, we highlight hybridization mosaics across three study systems containing taxa critical to widespread plant communities in western North America: , , and . The systems contain diverged taxa that co-occur across the landscape and hybridize readily. Hybridization among taxa has facilitated niche expansion into intermediate environments consistent with unique combinations of adaptive genetic variation, creating more continuity within each study system-study systems occupy ~820 to 270,000 km more geographic area by virtue of hybridization. Furthermore, hybrids are predicted to play important roles in future climates, as they may occupy 8 to 475% larger distributions compared to present. Convergent patterns signal mosaic hybridization as an underappreciated mechanism with broad ecological and evolutionary ramifications. Leveraging mosaic hybridization may assist the creation of restoration management plans that aim to mitigate the deleterious effects of habitat fragmentation on ecosystems in the context of climate change.
由于在异质景观中有着复杂的生物地理历史，北美西部许多广泛分布的植物分类群已分化为表型和基因上不同的谱系。当在地理上同时出现但环境不同的谱系进行异花授粉并形成占据独特环境生态位且不存在地理渐变群的杂种时，就会形成镶嵌杂交带。这扩大了亲本和杂种个体生长的总环境空间，导致地理分布范围更大、更连续。在这里，我们重点介绍了三个研究系统中的杂交镶嵌现象，这些系统包含对北美西部广泛分布的植物群落至关重要的分类群：[此处原文缺失具体分类群名称]、[此处原文缺失具体分类群名称]和[此处原文缺失具体分类群名称]。这些系统包含在整个景观中共同出现且易于杂交的分化分类群。分类群之间的杂交促进了生态位向中间环境的扩展，这与适应性遗传变异的独特组合相一致，在每个研究系统内创造了更多的连续性——由于杂交，研究系统占据的地理面积增加了约820至270,000平方千米。此外，预计杂种在未来气候中将发挥重要作用，因为与目前相比，它们的分布范围可能扩大8%至475%。趋同模式表明镶嵌杂交是一种未得到充分认识的机制，具有广泛的生态和进化影响。利用镶嵌杂交可能有助于制定恢复管理计划，旨在减轻气候变化背景下栖息地破碎化对生态系统的有害影响。
