Laboratory of Systematic & Evolutionary Botany and Biodiversity, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China.
BGI-Qingdao, BGI-Shenzhen, Qingdao, 266555, Shandong, China.
Nat Commun. 2019 Sep 13;10(1):4201. doi: 10.1038/s41467-019-12133-5.
As Charles Darwin anticipated, living fossils provide excellent opportunities to study evolutionary questions related to extinction, competition, and adaptation. Ginkgo (Ginkgo biloba L.) is one of the oldest living plants and a fascinating example of how people have saved a species from extinction and assisted its resurgence. By resequencing 545 genomes of ginkgo trees sampled from 51 populations across the world, we identify three refugia in China and detect multiple cycles of population expansion and reduction along with glacial admixture between relict populations in the southwestern and southern refugia. We demonstrate multiple anthropogenic introductions of ginkgo from eastern China into different continents. Further analyses reveal bioclimatic variables that have affected the geographic distribution of ginkgo and the role of natural selection in ginkgo's adaptation and resilience. These investigations provide insights into the evolutionary history of ginkgo trees and valuable genomic resources for further addressing various questions involving living fossil species.
正如查尔斯·达尔文所预测的那样，活化石为研究与灭绝、竞争和适应相关的进化问题提供了极好的机会。银杏（Ginkgo biloba L.）是现存最古老的植物之一，也是一个引人入胜的例子，说明人类如何拯救一个物种免于灭绝，并帮助其复兴。通过对来自全球 51 个种群的 545 株银杏树进行重测序，我们确定了中国的三个避难所，并检测到多个种群扩张和减少的循环，以及西南和南部避难所中遗留种群之间的冰川混合。我们证明了银杏从中国东部向不同大陆的多次人为引入。进一步的分析揭示了影响银杏地理分布的生物气候变量，以及自然选择在银杏适应和恢复中的作用。这些研究为银杏树的进化历史提供了深入的了解，并为进一步解决涉及活化石物种的各种问题提供了有价值的基因组资源。
