‘Rebel’ Earth Mother Probed Life’s Secrets

By Dr. Robert Thorson

Last weekend was magically beautiful. Mother’s Day, spring flowers, songbirds in chorus, students graduating, baby animals and the solstice still ahead. What a wonderful time to be alive!

Given my mood, the opinion columnist in me refused to cooperate. My “seek-and-point-out-someproblem” module was offline. So, I decided to celebrate my springtime joy by writing an obituary from dreary November of someone I admired, and who most of you probably never heard of.

Lynn Margulis, a distinguished evolutionary biologist at the University of Massachusetts Amherst, died last November at the age of 73. My three words for her scientific career are: “Germs are us.”

More explicitly, each of us is a colony of a colony of formerly free-living entities (let’s call them bacteria). Most readers probably already know that their body is a cooperative colony of specialized cells, each with a nucleus. What they may not know is what Professor Margulis helped teach us: Each of those cells is, in turn, a cooperative colony of bacteria that became more successful when working together than when against each other. (I think there’s a message here.)

Though I met Lynn only once a decade ago, and followed her career only from the sidelines, what I did know resonated with an obituary published in Current Biology by John Archibald. “She will be remembered,” he wrote, “as a gifted and giving teacher, an indefatigable champion of endosymbiotic theory, a staunch advocate of Lovelock’s Gaia hypothesis and an all-round skeptic of mainstream science.”

Two points. The technical word “endosymbiotic” means cooperating internally, as above. James “Lovelock’s Gaia hypothesis” is the notion that Earth — biosphere, atmosphere, lithosphere, hydrosphere — is one colossal, self-regulating entity. Though Lovelock likened Earth to an organism, Margulis correctly rejected this as being “anthropomorphic and unscientific.” Instead, she described Gaia as a “‘tough bitch,’ a complex ecosystem” that, like all ecosystems, self-regulates without volition.

Margulis was once nationally headlined as “Science’s Unruly Earth Mother.” How apt for the wee hours of sunrise on Mother’s Day, 2012, when I was drafting this column.

Margulis’ criticisms of mainstream science drove many of her colleagues crazy. Archibald wrote: “Amusing, exasperating, enlightening.” She “routinely dismissed results gleaned from reductionist methodologies in favor of holistic approaches.” As with most “scientific ‘rebels,’ she simply refused to doubt her own intuition. … Swimming against the scientific tide was in Margulis’ DNA. Stubborn and iconoclastic, brilliant and increasingly dogmatic. … An enigma … criticized and praised in equal measure.”

Her notoriety began in 1967 with a game-changing article: “On the Origin of Mitosing Cells,” which had famously been rejected by more than a dozen journals before acceptance. Though this case remains a burr in the side of scholarly peer review, I see it as a source of inspiration never to give up.

In her article, she proposed that discrete components (called organelles) within nucleated cells (called eukaryotes) were formerly unrelated types of bacteria that ended up cooperating. These organelles include the mitochondria that gives us energy via respiration, the chloroplasts that capture energy from the sun via photosynthesis, and the flagellae that motorize moving cells. Her interest in Gaia was a logical extension of what struck her as systemic beneficial interaction built into the biosphere (of which we’re part).

After a career of struggle, Margulis eventually gained the recognition she deserved. In 1983, she was elected to the U.S. National Academy of Sciences. In 1999 she was awarded the National Medal of Science by President Bill Clinton, and in 2008, the Darwin-Wallace Medal by the Linnaean Society of London.

Perhaps we should listen to her billion-year-old bacterial story as a parable, relax our defensiveness and let the natural spirit of cooperation happen.

Yes, it’s wonderful to be alive. It’s also wonderful to think about being alive.