How were the classification systems of Aristotle and Linnaeus similar? 

Both systems divided all living things into two major groups, animals and plants, but Aristotle's system had three sublevels each for animals and plants, while Linnaeus's system had six sublevels. Aristotle also divided animals on the basis of habitat and plants on the basis of stem differences, while Linnaeus divided all organisms mostly on the basis of morphology. Aristotle used common names for organisms, while Linnaeus used binomial nomenclature.