Margulis and the Five Kingdoms

 I mentioned Lynn Margulis to Jane Schellenberger, editor of Colorado Gardener magazine, and she agreed that Lynn was a person to know about. Consequently, my article, “Lynn Margulis: champion of the microcosmos,” will appear in the spring issue of the magazine. I created an illustration to accompany the piece that incorporates Margulis’ image with a graphic designed by her son, Dorion Sagan, which represents the Five Kingdoms of life on our blue planet.

The hand metaphor emphasizes that all life on earth is related on a fundamental level. The thumb represents the kingdom of bacteria, linked with a host of other microbial species that spread across the base of the hand. Scientists now believe that two Domains—larger classification units than Kingdoms—separate the Archaea (Archaebacteria) that may represent the original colonizers of the planet, from the Eubacteria, that ultimately gave rise to all the rest of modern life forms. The little finger represents the still microscopic, but more complex menagerie of Protoctista, that includes amoebae, ciliates, slime molds and other creatures you may have encountered in science class when you looked through a microscope. The other fingers represent the more familiar kingdoms of fungi, plants, and animals. Together with the inorganic parts of our “third rock from the sun” they form the Biosphere—a construct durable in its foundations, but fragile in the crystalline complexity of global interlocked ecosystems and the snowflake towers of human civilization.

Copernicus removed our illusion of being at the center of the universe. Darwin removed our illusion of being a special act of creation. Margulis stripped away yet another layer of ego, by pointing out that humans and all complex life forms are just microbial high rise condos. Good scientists have a way of keeping us humble, as long as we make the effort to listen.

A Tribute to Lynn Margulis (1938-2011)

      Lynn Margulis, a woman who fundamentally changed our collective understanding of biology in her lifetime, died November 24, 2011, at the age of 73. I never knew her personally, but followed her work for many years. She received a PhD from Berkeley in 1965 when I was still a sophomore at the University of Michigan. She changed some major paradigms in biology during her lifetime—an amazing feat of intelligence, insight, and courage. She wasn’t afraid to look around her while climbing the professional steeple of biological proficiency and compare what she was learning to what was known in other fields of study. She thus became controversial to mainstream biological orthodoxy. When asked once if she minded being categorized as controversial, she said that she didn’t consider her views controversial, she considered them to be right.

     She may have been hard to live with, both professionally and personally. She married science educator and astronomer, Carl Sagan, in 1957 and had two sons, Dorion and Jeremy. The couple divorced in 1963. Margulis met Thomas Margulis while living in the Boston area and married him in 1967. They had a son and daughter, but divorced in 1980. In an interview with University of Chicago Magazine in 2004 she said, “I quit my job as wife twice. It’s not humanly possible to be a good wife, a good mother, and a first-class scientist. No one can do it; something has to go.”

     Margulis served as a distinguished professor in geophysical science at the University of Massachusetts for many years. She lived in Amherst next door to Emily Dickinson’s house and felt a connection to this 19^th century poet. Her son Dorion, with whom she co-wrote several important books, said that she was an amateur Dickinson scholar. Her daughter, Jennifer Margulis, said Dickinson “just spoke to my mom” through her work.

     Margulis looked at life’s “big picture” and at some of the smallest organisms on the planet and recognized interconnections and synergies that others had failed to notice.

     For example, complex, eukaryotic cells of everything from protozoans to professors are actually a community of simpler, bacteria-like cells that fused into functional associations over the course of deep time. Mitochondria, the energy organelles in all eukaryotic cells, were once independent microbes, as were chloroplasts in plant cells and other organelles, like flagella.

     She helped James Lovelock with his Gaia theory—a supposition that the entire biosphere functions as a unit (Gaia) such that its various components work together as a kind of global thermostat, keeping the Earth in a condition favorable for life to survive. The theory, like all good scientific theories, was constructed to be testable. So far, most of its major tenets have survived intact.

     Margulis also believed that evolution, as often as not, occurs in mega-leaps when organisms acquire the genomes of other creatures wholesale. Her book, Acquiring Genomes, outlines the arguments in detail. The short version is that some organisms, in the attempt to eat others, acquire a kind of permanent indigestion when the prey organism becomes incorporated as part of the predator. Together, over time, they can become something new—and sometimes revolutionary.

     If you get a chance also look up the following titles:

     Five Kingdoms (written with Karlene V. Schwartz) (W.H. Freeman, 1998 3^rd addition): a visual tour of all life’s forms, arranged in five great kingdoms.

     Garden of Microbial Delights (Written with son, Dorion) (HBJ, 1988), a tribute to, and recognition of the fact that the world is essentially microbial and us macroscopic creatures are a decidedly late afterthought.

     In March, 2012, my book, Biodiversity and Food Chains, should be available from Infobase publishing (Chelsea House). I speak about Margulis and her work in Chapter 6, as well as that of James Lovelock. I hope another generation will come to know and appreciate her work.

     Lynn, the world needs more people who don’t just believe they are right, but have the intelligence, will, and perception to design testable ways to prove they are right and change the world in the process.