This is an eyelash mite. It lives exclusively in the follicles of the human eyelash. Now, it has, living upon it an even smaller mite which only live on eyelash mites. This mite has, in its gut, an even smaller organism which lives nowhere else. Human beings have an estimated 1,000,000,000 organisms living within and upon us many times the number of human beings which live upon the Earth. We are an entire ecosystem. No, we are several ecosystems. We have dry zones and wet zones. We have hot zones and cool zones. We are a planet unto ourselves. Only 10% of the DNA contained in our bodies is human DNA. The rest belongs to these microscopic hitchhikers.