Human beings may dominate the planet with our enormous cities and far-reaching technology, but we are, in fact, just one species among some 8.7 million that live together on planet Earth. One 2011 study published in the journal PLoS Biology estimated that “the various forms of life on the planet included 7.8 million species of animals, 298,000 species of plants, 611,000 species of mushrooms, 36,400 species of protozoa, and 27,500 species of algae.” And it’s worth noting that the researchers did not put the number of bacteria.
