[Bacteria are the] dark matter of the biological world [with 4 million mostly unknown species in a ton of soil].
E. O. WilsonHumanity is a biological species, living in a biological environment, because like all species, we are exquisitely adapted in everything: from our behavior, to our genetics, to our physiology, to that particular environment in which we live. The earth is our home. Unless we preserve the rest of life, as a sacred duty, we will be endangering ourselves by destroying the home in which we evolved, and on which we completely depend.
E. O. WilsonMost people are surprised when they hear my somber figures: we know of 2 million species of plants, animals and microorganisms, and we can give them each a scientific name and a diagnostic description. We know, perhaps generously, more than just a little bit of the anatomy in no more than 10 percent. We have done thorough studies in fewer than one-tenth of 1 percent. And the total number of species on Earth is unknown to the nearest order of magnitude.
E. O. Wilson