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地球上什么时候开始有仙人掌?又是如何演化成如今多姿多彩的模样?这些问题现在尚不太清楚。因为仙人掌类植物不容易成为化石,所以无从考证。按常识而论,仙人掌类植物的祖先应以与其他普通植物相似的原始形态出现,因为自然环境的剧烈变化,原先温暖湿润的气候,逐渐转变为空气干燥、
When did the earth start to have cacti? How has it evolved into today’s colorful appearance? These issues are not yet clear. Because cactus plants do not easily become fossils, so no research. Common sense, cactus plant ancestors should be similar to other common plants with the original appearance, because of dramatic changes in the natural environment, the original warm and humid climate, and gradually transformed into air-dried,