I read somewhere E. O. Wilson stating that were he to start over again he would go into research of life in the soil. He also said there is so little we understand about the things just beneath our feet.

We don't even know how to document it all when we extract DNA from soil. You might be able to put things into general families of species but too much is uncharacterized. Some research is opting to just consider things in terms of ecological niches occupied instead of absolute species found.

Even on, and in our feet.