The theory of evolution driven by competition is only part of the story, a new book reveals.
Excerpted from Sweet in Tooth and Claw: Stories of Generosity and Cooperation in the Natural World ©2022 by Kristin Ohlson. Reprinted with permission by Patagonia.
The view of evolution as a process driven by competition and selfishness was thoroughly shaken up in the 1960s by evolutionary biologist Lynn Margulis. She was fascinated by the microbial world; her daughter Jennifer Margulis says that she called herself a “spokesperson for the microcosm.”
In a paper that was rejected by fifteen scientific journals before it was published, Margulis pointed back to the earliest days of life on Earth and argued that single-celled organisms (bacteria appeared some 3.8 billion years ago) made a dramatic leap into multicellular complexity via symbiosis some one and a half billion years ago.
In this hypothesis, two different microorganisms lived in community — as bacteria still do, forming slimes and mats in which millions live and interact with each other — and merged to form a new and more internally complex kind of cell called a eukaryote. Those eukaryotic cells themselves went on to form symbioses to become multicellular organisms.
Eukaryotic cells contain bundled structures outside the cell nucleus — mitochondria, which produce energy, and, in plants, chloroplasts, which drive photosynthesis — and Margulis argued that both are remnants of formerly free- living bacteria. This line of thinking stretched all the way back to the work of early twentieth-century Russian scientists who embraced both Kropotkin and Darwin but were ignored in the West at the time.
When Margulis presented her work, it took ten years for most of the rest of science to stop damning her as a heretic, but her arguments are now widely accepted. Every bit of our bodies, as well as those of other animals, plants, and fungi, are made of eukaryotic cells — these minuscule bundles of cooperation that transformed Earth more than anything except for the emergence of life itself.
A friend who heard I was working on this book sent me a marvelous essay by neuroscientist Kelly Clancy for Nautilus magazine called “Survival of the Friendliest,” which introduced me to the concept of “relaxed selection.” As Clancy points out in the essay, natural selection — the weeding out of members of a species that have traits that make them less likely to survive, and the resulting surge of others with more helpful traits — can be “relaxed” by events outside an organism’s control, like a drop in the number of predators or the sudden increase in a food source or a long spate of fine weather, and this relaxation allows organisms the freedom to change and grow in new ways.
But selection can also be relaxed by the actions of the organisms themselves. “Evolution isn’t just selecting for bodies,” Clancy explained to me. “It’s selecting for behaviors, postures, mating dances, habitats. It’s beavers making dams, and humans making cities. It operates on a cultural level.”
The Amazing Ways Nature Cooperates — and We Benefit • The Revelator
Excerpted from Sweet in Tooth and Claw: Stories of Generosity and Cooperation in the Natural World ©2022 by Kristin Ohlson. Reprinted with permission by Patagonia.
The view of evolution as a process driven by competition and selfishness was thoroughly shaken up in the 1960s by evolutionary biologist Lynn Margulis. She was fascinated by the microbial world; her daughter Jennifer Margulis says that she called herself a “spokesperson for the microcosm.”
In a paper that was rejected by fifteen scientific journals before it was published, Margulis pointed back to the earliest days of life on Earth and argued that single-celled organisms (bacteria appeared some 3.8 billion years ago) made a dramatic leap into multicellular complexity via symbiosis some one and a half billion years ago.
In this hypothesis, two different microorganisms lived in community — as bacteria still do, forming slimes and mats in which millions live and interact with each other — and merged to form a new and more internally complex kind of cell called a eukaryote. Those eukaryotic cells themselves went on to form symbioses to become multicellular organisms.
Eukaryotic cells contain bundled structures outside the cell nucleus — mitochondria, which produce energy, and, in plants, chloroplasts, which drive photosynthesis — and Margulis argued that both are remnants of formerly free- living bacteria. This line of thinking stretched all the way back to the work of early twentieth-century Russian scientists who embraced both Kropotkin and Darwin but were ignored in the West at the time.
When Margulis presented her work, it took ten years for most of the rest of science to stop damning her as a heretic, but her arguments are now widely accepted. Every bit of our bodies, as well as those of other animals, plants, and fungi, are made of eukaryotic cells — these minuscule bundles of cooperation that transformed Earth more than anything except for the emergence of life itself.
A friend who heard I was working on this book sent me a marvelous essay by neuroscientist Kelly Clancy for Nautilus magazine called “Survival of the Friendliest,” which introduced me to the concept of “relaxed selection.” As Clancy points out in the essay, natural selection — the weeding out of members of a species that have traits that make them less likely to survive, and the resulting surge of others with more helpful traits — can be “relaxed” by events outside an organism’s control, like a drop in the number of predators or the sudden increase in a food source or a long spate of fine weather, and this relaxation allows organisms the freedom to change and grow in new ways.
But selection can also be relaxed by the actions of the organisms themselves. “Evolution isn’t just selecting for bodies,” Clancy explained to me. “It’s selecting for behaviors, postures, mating dances, habitats. It’s beavers making dams, and humans making cities. It operates on a cultural level.”
The Amazing Ways Nature Cooperates — and We Benefit • The Revelator