by Lynn Margulis and Dorian Sagan
This piece was originally published in Home! A Bioregional Reader, edited by Van Andruss, Christopher Plant, Judith Plant, and Eleanor Wright, New Society Publishers, copyright 1990.
Fossil evidence of primeval microbial life, the decoding of DNA, and discoveries about the composition of our own cells have exploded established ideas about the origins of life and the dynamics of evolution on earth.
First, they have shown the folly of considering people as special, apart and supreme. The microscope has gradually exposed the vastness of the microcosm and is now giving us a startling view of our true place in nature. It now appears that microbes— also called micro-organisms, germs, bugs, protozoans, and bacteria, depending on the context—are not only the building blocks of life, but occupy and are indispensable to every known living structure on the earth today. From the paramecium to the human race, all life forms are meticulously organized, sophisticated aggregates of evolving microbial life. Far from leaving micro-organisms behind on an evolutionary “ladder,” we are both surrounded by them and composed of them. Having survived in an unbroken line from the beginnings of life, all organisms today are equally evolved.
This realization sharply shows up the conceit and presumption of attempting to measure evolution by a linear progression from the simple—so-called lower—to the more complex (with humans as the absolute “highest” forms at the top of the hierarchy). As we shall see, the simplest and most ancient organisms are not only the forebears and the present substrate of the earth’s biota, but they are ready to expand and alter themselves and the rest of life, should we “higher” organisms be so foolish as to annihilate ourselves.
Next, the view of evolution as chronic bloody competition among individuals and species, a popular distortion of Darwin’s notion of “survival of the fittest,” dissolves before a new view of continual cooperation, strong interaction, and mutual dependence among life forms. Life did not take over the globe by combat, but by networking.
Excerpted from Micro-cosmos: Four Billion Years of Microbial Evolution, New York: Summit Books, 1986.
Lynn Margulis (1938-2011) was a biologist and writer whose work dramatically transformed the modern understanding of of the importance of symbiosis in evolution and the evolution of cells with nuclei. She received the National Medal of Science from President Bill Clinton in 1999.
Dorian Sagan (b. 1959) is a writer and the son of Lynn Margulis and Carl Sagan. His many publishing credits include a number of books co-written with his mother, as well as a biography of her.