Why are some of carl linnaeus's classifications of organisms incorrect

Some of Carl Linnaeus' classifications of organisms were incorrect because he classified them based off of appearances and actions instead of actual relationships. For instance, bats were classified as birds because they flew, and whales were classified as fish because they had fins and swam underwater.
The mere fact that some of his classifications were off, however, does not reduce the marked effect that it had on the advancement of scientific thought in the present world. His findings have greatly influence the modern classification system in many ways.

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