The principle of evolution says that the species which is best adapted for an environment, or a particular niche in that environment, flourishes at the expense of other species less well adapted for that niche. It is in this sense, adaptation, that evolutionary competition arises—not necessarily based on who is the more ruthless killer or fastest eater. But being too snugly fitted into your niche can be a trap when that niche changes.
Sharks—ruthless killers and fast eaters themselves—seem to be the exception. They predate the dinosaurs by some 200 million years, and they have evolved very slowly since then, according to the fossil record based on their teeth.1 As the marine biologist Matt Hooper observed in Jaws: “What we are dealing with here is a perfect engine, an eating machine. It’s really a miracle of evolution. All this machine does is swim and eat and make little sharks.” In the open ocean, that appears to be good enough, so long as you’re near the top of the food chain. And if a bigger predator comes along—a plesiosaur or a whale with a taste for shark meat—then being good at making lots of little sharks might even save the species.
In most evolutionary niches, however, the question for a species is not good or bad adaptation, survival or death, yes or no, but instead better or worse. If you are a Galapagos finch with a long, thin beak, perfect for plucking tiny seeds out of the cracks in the rocks and breaking their delicate shells, you’re going to be at a disadvantage when the bushes serve up big, tough seeds that don’t roll into cracks and are better broken by a short, stout beak.2 But that doesn’t mean you starve and die out. You just have to work harder and eat less than your stout-beaked cousins.
And of course, there are imaginary cases of total maladaptation. Transport an orchid from the Amazon jungle to the Sahara desert, and it dies. But the orchid on its own never tried to survive in the desert to begin with.3
It is, however, a fact of evolution and of life in general that the more perfectly you are adapted to fit your niche—that is, the more successful you are—the more vulnerable you become to changes in the environment. The best example is parasites and symbiotes: kill their host, kill the species.
That principle also works in reverse: if your species becomes dominant in a stable environment, your genome settles into a pattern of virtual standstill, or equilibrium, in terms of development. When individuals do arise with mutations that change their bodily fitness, so they are less well adapted to the niche, those mutations and the individuals who carry them are quickly weeded out. The herd and its predators also tend to cull the oddities: the strange, the malformed, the sickly, the malcontent. The population loses its phenotypic diversity, if not its innate genetic diversity. Then a new and more rapidly evolving parasite can arise to exploit the dominant genome and wipe out large populations.4
Among humans, the utility and popularity of certain plants and animal species, tailored as seeds and embryos by selective breeding or gene modification and nurtured by special techniques such as irrigation and feed lots, fertilizers and antibiotics, raises this group vulnerability. We have populated the world with species of corn and wheat, chickens and cows, that are physically and genetically uniform. Wily bacteria and the vagaries of climate are constantly prowling the outskirts of our pastures and fields, looking for an opportunity to make a kill.5
We’ve also populated the world with humans who are becoming more uniform and less adaptable. As farms and cities arose, people became less able to forage in the woods for their survival. As farms become mechanized, people move into cities seeking work in factories and service. As factories become automated, people become less handy with tools and practical matters. And as service jobs become mechanized, people become less socially adept. They live through work and social exchanges moderated by the dream world of technology.
In the “less developed” countries, we have rural regions where people know how to farm but not hunt—which is probably a blessing, because we’ve also eliminated most of the huntable species. In the cities of “economically developed” countries, we have people who know how to manipulate a computerized database to get the things they want, but they would starve on a working farm.6
We used to make products designed to be repaired and maintained, things that will keep going past their obsolescence if you or a local mechanic know a bit about machinery. In the last thirty years or so, however, every appliance from automobiles to refrigerators, typewriters to cash registers, has become digital. They depend on chips and codes that either work or don’t. When these appliances fail, the best you can do is throw them away and buy a newer model. Maintain-and-repair has become diagnose-and-replace.
We build factories with few laborers and no craftsmen; they employ mostly accountants, warehousemen, and janitors. Machines do almost all of the manufacturing, according to plans and orders written by people in other cities and removed in time by months or years. The machines are fast and efficient, perfected for making the products they were designed to make. But to retool for a different product—to make refrigerators instead of cars, for example—is a major undertaking. It’s cheaper to tear down the factory and build a new one.
Believe that I like technology; it’s a fascinating subject. I am no luddite. And the technology I’m describing—both in terms of farmed species and digital factories—has given us in the western and developed countries a life of leisure and wealth of goods beyond the imagining of people just two hundred years ago. If this pattern goes on, if our adaptation to this niche becomes ever more perfect, then the world of 2211 will be as incomprehensible to us as today’s urban living would be to a European of 1811.
But taking the majority of humans out of the active business of providing a living may be a trap. We can provide for them materially. Mechanized farming and manufacture creates enough wealth to feed, clothe, house, and entertain the world. But how do we provide for them psychologically? A quarter of a million years or more of scratching the dirt for roots and hunting with a sharp stick has ingrained pride of self-sufficiency and personal skills in the human psyche. We really were not made to sit on a couch, drink beer, and watch other people play football—or not all day, every day.7
More than that, a society whose needs and their fulfillment are in such perfect balance, where supply is matched to demand by computer prediction, and the necessities of life are provided by a complex technology that only a fraction of the population understands, is terribly vulnerable. Economists in their modeling isolate such cases with the phrase “other things being equal,” ceteris paribus. But all else is never equal or static.
The more successful you become, the more efficiently you harvest your niche, the more vulnerable you become to the disruptions that punctuated equilibrium was meant to exploit. In a world of hunter-gatherers, who know hunger and scrambling are the norm, an ice age or an asteroid strike does not wipe out the species. In a world of urban dwellers, who think meat and bread come from the supermarket, a failure of the fuel supply or the electric grid, let alone a cosmic catastrophe, will mean widespread death.
I don’t dwell on these things, no one can. We can’t put the genie of technology back in the bottle. And I wouldn’t wish the life of a hunter-gatherer or a poor dirt farmer on anyone—it’s that life for which the phrase “nasty, brutish, and short” was coined.
Still, we can be too perfectly specialized, too modularized, interconnected, and trained in the esoterics of a surprisingly fragile system. For all our sophistication, we live on a tectonically active planet under a variable star surrounded by rocks and ice in unstable orbits. And ceteris is never paribus.
1. As sharks have no bones, only cartilage, not much else survives from the distant past. See Shark Evolution from the ReefQuest Centre for Shark Research.
2. See Jonathan Weiner’s The Beak of the Finch.
3. Human intervention does change things. We’ve made corn and cotton grow in sandy soils and arid regions by selective breeding and arranging for irrigation and fertilizers. But their survival here is a result, at best, of directed evolution and lots of pampering.
4. But never—or seldom—all of the individuals in a species. The principle of punctuated equilibrium, described in 1972 by Stephen Jay Gould and Niles Eldredge, suggests that evolution is not necessarily a slow and gradual adaptation as once thought. Populations become stable in beneficial environments, and the effects of mutations over time are largely negative, so they die out. But when the environment changes, placing stress on the population through lack of food or other adverse conditions, mutations may suddenly offer advantages. The mutation rate doesn’t change so much as the opportunities offered by changes in design increase. And in some cases, such as the recombination of parts of chromosomes in cells under environmental stress (that is, the “jumping genes”), the mutation rate does actually tend to increase.
5. I’m not necessarily speaking of human-induced climate change through carbon emissions. We live on a tectonically active planet under a variable star. Flood and drought, the advance and retreat of the ice, plagues and locusts, have long been artifacts of human history.
6. This is certainly true in the U.S., where farms are mostly corporate factories with the land dedicated to one species of one plant or animal. In traveling down the Po Valley in Italy, I saw more family farms, with orchards and vineyards planted among the fields. Most of Europe seems to have developed this way. With smaller farms more closely tied to smaller, family-owned boulangeries and charcuteries in town, the Europeans seem better prepared for apocalypse.
7. See my blog Automation, Work, and Personal Meaning from February 27, 2011.
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