DNA mutates and passes on in generations. Plants as objects are composed of DNA, life span and display features. Population is affected by the habitat (environment) that has its own display features. The habitat’s health is affected by multiple forces. DNA会发生变异并代代相传。物种由DNA、寿命和显示特征组成。物种数量受环境影响。 环境受到多种力量的影响，也有自己的显示特征。