Shared features. Humans are not the only species with two eyes, two ears, a nose, and a mouth. We're also not the only species with four limbs, reproductive organs, and opposable thumbs. But, what's interesting is that they aren't all the same. Out eyesight is better than a bat's, but the bat has better hearing. We can run faster than a turtle, but a cheetah can run faster than us. So, despite sharing these traits, they have been enhanced or degraded based on what was beneficial in that environment.
And, while we may not look like microscopic organisms in the ocean, it's possible to look to living creatures that are similar to them, and start following a ladder of relatives where our features start to manifest. For example, many tiny organisms have eyes or reproductive organs. The tree of life is a fascinating web of beautiful creatures.