When people think about evolution, they often conjure up a mental picture that has humans branching off on the descendants-of-apes limb of the big animal-kingdom family tree. However, if you look further back in evolutionary history, you will see evidence that humans are also related to fish. That's right – fish! The evolution from fish to human was obviously a long, drawn-out process; however, the traits that humans inherited from fish show an uncanny resemblance in many instances.
If you're still wrapping your mind around the whole theory of evolution or are getting hung up on our simian brethren, prepare to have your mind blown by our aquatic ones.