Most of "you" is a composition

If you count all the living cells in your body, most of them are not human. The vast majority, by a factor of ten, are microbes. Granted, most of these are in the gut, but we are inhabited all over-- even covering our eyeballs. Curiously, each ecosystem is different: Our microbiology is personal and unique.

We know that we share many of the same genes as other animals. And we are also hosting many of the same microbes. Our symbiotic biosphere is as unique as our fingerprint.