19.0：简介
- Page ID
- 202221
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地球上的所有生命都是相关的。 进化论指出，人类、甲虫、植物和细菌都有共同的祖先，但是数百万年的进化使每一种生物都形成了今天的形态。 科学家认为进化是理解生命的关键概念。 自然选择是最主要的进化力量之一。 自然选择的作用是促进增加生物体存活和繁殖机会的特征和行为，同时消除对生物体有害的特征和行为。 但是，顾名思义，自然选择只能选择，它不能创建。 新特征和行为的引入落在了另一种进化力量——突变的肩上。 个体之间的突变和其他变异来源，以及作用于个体间的进化力量，会改变种群和物种。 这种过程的结合造就了我们今天所看到的生活世界。