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距今一亿七千万年前的中生代侏罗纪,欧亚、北美及南半球,几乎到处都生长着种类繁多的银杏类植物,大约有15属、20种。到了白垩纪,地球上广大地区气候骤冷,这类植物逐渐衰退。第四纪初的冰川运动,致使欧亚及北美大陆的银杏全部灭绝,亚洲的银杏也濒于绝种。然而我国华中、华东局部地区,由于地形复杂和冰川没有到达,这里生长的银杏幸免于难,成为我国独存的“活化石”。目前在其自然分布区的风景名胜区,尚有众多的银杏古树,如北京古刹谭柘寺、河北遵化五峰山禅林寺、河南济源紫微宫、江西庐山莲花洞、浙江杭州五云山、湖北通山、
About 170 million years ago, the Mesozoic Jurassic, Eurasia, North America and the southern hemisphere have almost all kinds of ginkgo plants growing around 15 genera and 20 species. By the Cretaceous, the climate on most parts of the globe was getting cold and the plants gradually declined. The glacier movement in the early Quaternary caused all the ginkgo in the Eurasian and North American continents to be extinct, and the ginkgo in Asia was also on the verge of extinction. However, in some parts of central China and eastern China, because of the complex topography and the unavailability of glaciers, the ginkgo growing here survived and became the “living fossil” that was the only one in our country. Currently in its natural distribution area of the scenic spots, there are many ancient ginkgo trees, such as Beijing Temple Tan Temple, Hebei Zunhua Wufengshan Buddhist Temple, Henan Jiyuan Ziwei Gong, Lotus Hill in Jiangxi Lushan, Hangzhou, Zhejiang Five Yunshan, Hubei Tongshan,