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红杉、巨杉、落羽松和我国的银杏、水杉、水松都属于世界上最古老的树种。距今六千万年至一亿年前,红杉和巨杉曾遍布于北半球,由于第四纪冰川的影响,把欧、亚各地的这种杉树全部摧毁了,目前仅在北美西部太平洋沿岸保留有这种残遗的古老树木。红杉和巨杉过去被认为是同一个属,1939年有人发现两者的染色体数目不同,加之一系
Sequoia, Sequoia, Taxodium and China’s ginkgo, Metasequoia, cork belong to the world’s oldest tree species. Sequoia and Sequoia ever existed in the northern hemisphere from 60 million years ago to 100 million years ago. All these cedar trees in Europe and Asia were totally destroyed due to the influence of the Quaternary glacier. At present, only the western North Pacific Ocean The remnants of ancient trees are preserved along the coast. Sequoia and giant cedar in the past is considered the same genus, in 1939 it was found that the number of chromosomes between the two different, combined with a system