Outgrowing 'Survival of the Fittest'

Cooperation guides evolution

The strongmen now running our country would like to think they’re merely following evolution’s dictates. By proclaiming their own supremacy, or that of their race and/or gender, they imagine they’re guided by an inevitable evolutionary process often dubbed “survival of the fittest.”

They’re living in the past.

Focusing on natural selection—the actual name for the evolutionary process distorted by the phrase “survival of the fittest”—overlooks our modern understanding about how evolution actually works. It’s not brute force guiding the most successful evolutionary gambits. It’s cooperation that reigns supreme.

The evidence sits right in our bodies. It’s alongside our DNA.

DNA includes the “good genes” touted by government officials such as Donald Trump and Elon Musk. Trump describes his own genes and those of his supporters as superior to others. (See below for links.) Musk similarly considers his genes superior and feels called to spread them around by having as many children as possible. While their interpretations echo the Nazi approach to eugenics, nature’s ways point to something else altogether.

In every cell in your body, you can find foreign bodies—foreign in that they have DNA that differs from your own—cooperating with other parts of the cell in an effort to keep you healthy and energized.

For instance, the DNA in the nucleus of each of our cells differs from the DNA defining our own heredity, as microbiologist Lynn Margulis demonstrated in research starting in the 1960s. This applies to all the cells in our bodies boasting a nucleus—including those comprising our livers, kidneys, lungs, skin and bones, not to mention those acting on behalf of our immune systems.

Even cells without nuclei contain foreign bodies. That’s because the powerhouses known as mitochondria similarly sport a different set of DNA than that of the host benefiting from their assistance. Mitochondria break down carbohydrates to fuel our movements and anything else requiring energy.

This speaks to a symbiotic relationship. Our cells cooperate with two types of foreign bodies, in effect, to direct cellular activity and provide the energy for all human activity. Their mysterious immigration long ago into our cells worked for everyone’s benefit.

The same holds for nature’s true powerhouses, the chloroplasts in plants. They launch the whole food chain by using sunlight to make carbohydrates out of carbon dioxide and water.

These chloroplasts started out as independent bacteria. They’re the ones who, many billions of years ago, converted our planet from one overwhelmed by carbon dioxide to one sporting enough oxygen to bring on the rise of animals. Some of them eventually allied with plant cells.

Margulis was a long-time fan of bacteria. She died in 2011, after facing down decades of challenges in time to see her theory, known as cell symbiosis, become accepted textbook science.

Symbiosis beyond the cellular level also occurs between different species, from legumes to lichens to Homo sapiens.

Symbiotic bacteria live in root nodules of mesquite and other desert trees, helping them deal with relatively infertile desert soils. Mesquite trees provide the bacteria with shelter—visible as bumpy nodules on their roots—and carbon for food. In return, the bacteria convert nitrogen from the air into a form the tree can use.

Lichens offer another example of symbiosis. In the case of lichen, fungi create a microhabitat that suits some species of algae enough that they’ll willingly share the sugars they’ve produced with the fungi. In exchange, they receive some minerals and a shady spot to survive. The result is the typically long-lived lichens often seen growing in circular shapes on trees in damp forests, rocks and even gravestones.

As for humans, we contain at least as many inner bacteria as human cells—even without counting the bacteria such as mitochondria that live within every cell.

Gut bacteria living in human intestinal tracts are now considered important for good health. In the most dramatic example of this, gelatin pills holding healthy feces have been used in “bacteriotherapy” to deliver a sample of intestinal bacteria to those suffering from Clostridium difficile. The recolonization of healthy bacteria often can resolve this otherwise often fatal condition, more commonly known as “C. diff.”

This research provides further evidence that no human is an island. We Homo sapiens are teaming with bacteria and other foreign bodies in our cells and in a microbiome that forms an internal support system.

Although research in the past quarter century has brought more fully to light the importance of bacteria in the human microbiome, Margulis had something to say about this in her 1998 book, Symbiotic Planet:

Not only are our guts and eyelashes festooned with bacterial and animal symbionts, but if you look at your backyard or community park, symbionts are not obvious but they are omnipresent. Clover and vetch, common weeds, have little balls on their roots. These are the nitrogen-fixing bacteria that are essential for healthy growth in nitrogen-poor soil. … We are symbionts on a symbiotic planet, and if we care to, we can find symbiosis everywhere. 

So symbiosis, a form of cooperation, actually defines our evolution. Even our ongoing existence.

Politicians and civilizations seeking to exterminate the enemy within, foreign and otherwise, aren’t emulating evolution as we know it.

The people and societies acting with mutual cooperation are the ones actually following the laws of nature. It’s in our genes.

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Melanie Lenart is an environmental scientist and journalist living in the U.S. Southwest who posts Mondays, Wednesdays and Fridays. She plans to post more on natural selection next week, in the context of Gaia theory.

Notes and Resources

Trump’s touting of ‘racehorse theory’ tied to eugenics and Nazis alarms Jewish leaders. By Seema Mehta, published in the Los Angeles Times Oct. 5, 2020.

Trump and Musk are obsessed with genetics– but there’s no science behind their simplistic views. By Jonathan Roberts, published in the Guardian, Dec. 30, 2024.

Lynn Margulis and the endosymbiont hypothesis: 50 years later. By M.W. Gray, 2017, in Molecular Biology of the Cell 28(10), 1285-1287.

Lynn Margulis, Evolution Theorist, Dies at 73. By Bruce Weber in The New York Times, Nov. 24, 2011 / https://www.nytimes.com/2011/11/25/science/lynn-margulis-trailblazing-theorist-on-evolution-dies-at-73.html

Revised estimates for the number of human and bacteria cells in the body. By R. Sender, S. and R. Milo, 2016, PLoS Biology, 14(8).

Fecal Transplantation (Bacteriotherapy), accessed from John Hopkins Medicine website on Jan. 21, 2021.

Symbiotic Planet: A new look at evolution. By Lynn Margulis. New York, NY: Basic Books.