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"In 2007, I read a study by John Jost and his fellow researchers that found that conservatives react differently to death than leftists. They fear it more. How could that be, I wondered ? Aren’t rightists the tougher of the two political groups—the self-described adults in a room full of leftist children ?
That question inspired me to do research on the science that explains the evolutionary nature of human politics, everything from archeology and neurology to biology and genetics. What I discovered was that conservative fearfulness and toughness are logically joined in early human history. Early humans feared more because everyone around them inspired more fear. And because of that greater danger, fearfulness became an adaptive trait that was hard-wired into the genome. Without it, you did not survive. Conservatives are the descendants of those first humans.
That insight prompted me to begin thinking about conservatism and liberalism in evolutionary terms. The result is this book." (p.X)
"Rightists and leftists differ biologically as well as ideologically. Each group evidences more or less of certain personality traits such as Openness to Experience or Need for Closure that are due to temperament rather than acculturation. Rightists are by nature more fearful, leftists more experimental. Such trait differences are rooted in biology and governed by genes. How did such different traits emerge in the same species ?
Traits are the result of adaptation to an environment. Donald Trump is different from most of you reading this book because your ancestors and Trump’s ancestors lived in different environments that posed distinct survival challenges. Each environment prompted the evolution of radically different adaptive behaviors. The evolutionary rule is: geographic isolation plus genetic diversification equals population segregation (and, in some cases, speciation).
For example, over the course of 11,000 years, Tibetan highlanders adapted to a high-altitude environment by acquiring a variant of the EPAS1 gene and evolving an ability to process scarce oxygen more easily than lowlanders. Tibetan women’s bodies evolved to increase blood flow and oxygen delivery to the uterus, lessening the chances of low-weight babies and increasing the chances of survival in the harsh climate.
Darwin’s finches differ from one another for similar reasons. They populate the Galapagos Islands, sometimes one species to an island. Although descended from a single common ancestor, they evolved distinct beaks over time, and each beak is suited to finding food on a particular island. Some beaks are long for rooting out bugs under rocks, while others are blunt for cracking nuts. Like Darwin’s finches, your ancestors and Trump’s lived on different islands ; only they were islands in evolutionary time, different moments in human history. Rather than evolve different beaks, they evolved different brains and different adaptive behaviors.
Signs suggest Trump Island was a brutal place. To survive, Trump’s ancestors had to be brutal themselves. They competed remorselessly and selfishly with other small kin-based hunting bands, creating a static-filled situation of anxious fear regarding out-group people and a legacy of prejudice and racism in this strain of our species. The ancestral Trumps hoarded resources and denied others access to them—much as Trumps do today. They treated others’ needs with callous indifference because being generous did not pay off in the grand competitive scheme of things. One’s obligations to others extended to the rim of one’s kin band.
The hunting bands of the archaic environment were authoritarian, as Trump and his followers are still. Quick responses to danger got the hunting band to the end of the day, and such fast responses are best mobilized by a clear command structure with a single leader with complete authority. Because the survival of one depended on the survival of all, bonding with fellow band members was essential. In consensus was safety, as also loyalty. Dissidents were a danger to survival and were bullied or ejected and fell in the hierarchy. All had to know their place and stick to it. The rule of life was dominate or submit.
Trump Island came early in human history, and that accounts for why Trump’s behavior seems so archaic at times. It seems so because it is so. The most archaic aspect of Trump is dominance behavior. Trump regularly scowls at adversaries in an attempt to intimidate them. During one debate with Hillary Clinton, he prowled the stage behind her, looming over her physically. Such dominance behavior once served a survival purpose. Those good at dominance stood a better chance of controlling the distribution of resources (one of which was, of course, women) in their hunting band." (pp.1-2)
"Studies show leftists favor smiling to scowling and equality to dominance. That is the case because their island in evolutionary time—let’s call it Obama Island—required very different adaptive strategies. Signs suggest Obama Island was a more crowded place than Trump Island. Smiling is a more sociable activity than scowling. It forges links with others and fosters reciprocity. Such reciprocity would have been helpful in a world where early humans were forced to live in greater proximity by environmental adversity. In such a novel situation, small kin-based hunting bands had to help one another rather than kill one another to survive. Former enemies on Trump Island had to become friends on Obama Island—or at least not murderous adversaries. The changes in the environment created new survival exigencies that required more cooperation and less competition between hunting groups. Kin and non-kin had to get along for the first time.
That would explain the entry of more smiling behavior and greater cooperativeness into the human repertoire of traits—in leftists at least. In studies, rightists score low for smiling behavior and are more competitive than cooperative. But not everyone in a population has to acquire a new trait for it to be adaptive. If just one person is inventive enough to figure out how to keep a fire going for weeks rather than hours, all will benefit. If she finds a like-minded mate, a new subpopulation begins to emerge. Something similar occurred on Obama Island. Some of our ancestors evolved traits such as cooperativeness that aided the survival of all even though not everyone acquired the trait. They gravitated to others similar to themselves—using an early version of facial recognition technology to detect each other if recent neuroscience is to be believed.6 Eventually, a new subpopulation or genotype emerged. Leftist traits became a permanent feature of our genome—in some, at least.
The difference between Trump Island and Obama Island, between rightists and leftists, tells us that our species did not evolve in unison. The same adaptive traits did not emerge in the entire human population at the same time. Instead, different traits were adaptive in different sub-populations at different moments in human history. At one point in time, it paid to hoard resources, to callously deny others access to them, and to treat out-group people with hostility. It paid to be rightist. But at another point, on a different island in evolutionary time, it made more sense for survival if at least some of our ancestors evolved the capacity to share resources and treat out-group people with kindness. It paid to be leftist.
Trump Island came first. Very early human history was harsh, and you had to be harsh to survive in it. Obama Island came later, as new environmental challenges obliged some of our ancestors to evolve behaviors such as experimentation and cooperativeness that were newly beneficial to survival. The result is two distinct sub-populations living in fractious cohabitation, arguing over the future direction of our species. That is the origin of human politics." (pp.2-4)
"According to the standard model of evolution known as the “evolutionary synthesis,” evolution occurs through accidental changes in the human genome. David Reich summarizes the process in the following way:
The genome is a sequence of about three billion paired chemical units that can be thought of as letters—adenine (A), cytosine (C), thymine (T), and guanine (G)—that are almost always the same between any two genomes, but occasionally are different. Between any two copies of a human genome, there is typically about one difference in every thousand positions. That’s about three million differences.
The differences Reich refers to are called single nucleotide polymorphisms. Changes in a single nucleotide—from C to A, for example—during reproduction can have significant downstream effects on health or behavior if the new variant of the gene attains sufficient frequency to become fixed. For example, a single polymorphism gave rise to a susceptibility to type 2 diabetes.3 Not all accidental changes in a base nucleotide are so deleterious. A variant of APSM, a gene controlling head size, swept to high frequency under strong positive selection in the past 5,800 years. As a result, most humans now have slightly larger crania than their ancestors had 6,000 years ago.4 According to this model of evolution, the genome routinely makes mistakes of transcription or copying, and some are beneficial.
Steven Pinker notes that violence declined in human life over the past millennia. How might the standard model of evolution account for this beneficial change ?" (p.6)
"Only 5% of the human genome is functional. Some genes—between 20,000 and 25,000—make proteins that manufacture components of our physiology, from brains to the chemicals that fuel violence, while others—about 8% of functional genes called transcription factors—regulate gene operation. NR2E1 performs two functions. It makes eyes, but in its spare time, it regulates aggression. Imagine an older version of NR2E1 that only made eyes. The transmission of its nucleotide sequences during reproduction routinely gave rise to single nucleotide polymorphisms. One of those polymorphisms resulted in a new variant governing a new trait—greater control over aggression—that benefitted from positive selection. People who acquired the variant behaved less violently and appeared more attractive to potential mates, or they avoided the violent conflicts that killed others, allowing them to survive and reproduce at higher rates. As the new variant increased in frequency over time, it underwent selection and swept through the human population. As a result, humans became less violent—at least theoretically.
A single polymorphism is usually not enough to affect behavior or physiology. Genes work in webs, with a host of small increments contributing to large effects, and one variant’s action often depends on the action of others. For BDNF to be active in the anterior cingulate cortex where it wards off depression, GAI1/3 must be at work simultaneously in the hippocampus.6 Some gene variants depend on environmental conditions. The gene polymorphism TPH1 A779C fosters creativity but not if authoritarian parenting is present.7 Temperament can also affect gene variants. Young men with a particular variant of MAOA, if they were abused as children, can engage in antisocial behavior when older. But if they are temperamentally sensitive, they avoid the adverse effects of mistreatment and score lower for antisocial behavior. Sensitivity associates with greater neuronal and behavioral plasticity, and plasticity enables adjustment to mistreatment. Behaviors such as chronic smoking can affect the functionality of genes. Daily smoking determines if a gene is likely to contribute to suicide in schizophrenia patients. Geography is also a factor. One gene variant behaves differently in North America, where it is associated with bipolar disorder, than in Asia, where it is not. Genetic studies are difficult to replicate, and one reason may be that each population studied, although apparently identical demographically, varies in dozens of ways, ranging from temperament and physical location to co-present genetic factors and personal habits.
Eva Jablonka and Marion Lamb propose several alternatives to the standard model of evolution. For example, some evolutionary change occurs as a result of non-genetic mechanisms.13 Epigenesis means “outside genes,” and evolutionary theorists like Jablonka think epigenetic routes are another way for information to be passed from parent to daughter cells in a way that fosters evolution. Our genes come to us as deoxyribonucleic acid (DNA) strands. In the process of communicating information from adult to offspring, the DNA strands are wound around histone proteins, organized into nucleosomes, and compacted into chromatin fiber for placement in chromosomes. The process of transcribing and transporting relies on ribonucleic acid (RNA), an acid which can make changes to genes before they are put to work. Some of the changes are accidental.
But some changes have a purpose and are governed by transcription factors— regulatory genes such as LCLAT1, which controls a process called acetylation that enhances protein formation. Gene regulation is also carried out by methylation, which controls gene expression by turning genes off. Methyl molecules attach to targeted sites on DNA strands during transcription in order to inhibit gene functioning. In contrast, acetylation promotes gene activity. Such changes in gene regulation can be heritable, and regulation has been important in recent human evolution. Adaptive divergence in our species has been primarily driven by regulatory changes. According to this model of evolution, the reduction in violence resulted from increased regulation of gene expression by epigenetic mechanisms such as methylation that silence genes such as MAOA that are responsible for violence." (pp.7-8 )
"A third way that evolution occurs is as a result of changes to genes caused by changes in behavior. To return to the example of violence, it is possible that at some point in the past, especially alert ancestors realized that violence was more harmful than helpful to themselves and to their families and decided to change their behavior. As their more pacific behavior produced higher survival rates, others were inspired to adopt the new nonviolent way of living. [...]
A fourth way that evolutionary change occurs, according to Jablonka and Lamb, is as a result of the transmission of information through the niche environment that we have built for ourselves. Certain species have evolved the ability to offload important tools of development into the niche environment, where they can be stored and retrieved when needed. Parents are especially good storage lockers. Rat pups need their mother to lick them if all of their genes are to be activated. The young of certain rabbit species could not survive if rabbit mothers did not feed their feces to their young, providing them with essential information for finding food.
Many of the processes that sustain modern human life depend on niche supports. Cognitive tools such as mathematics that maintain civilization at its current level require education." (pp.9-10)
"Pinker argues that a humanitarian turn in human history led to less violence. Different ideas and new norms lodged in symbolic form in our niche environment conducted human behavior in less violent directions. The new behavior was sustained from generation to generation by educational, governmental, and religious institutions that reinforced learning and nurtured nonviolent behavior.
Ideas and norms are representations, and an important feature of our cognitive functioning is mental representation. Mental representation serves a regulatory function in the brain by controlling emotional responses such as anger that fuel violence. Images of angry faces provoke fearful responses in some people that are at the same time neurochemical reactions. Eye neurons connect to brain neurons, and those neurons end in the amygdala, which responds to threats—such as images of angry faces—by producing norepinephrine, which makes our body tense and get ready to flee or fight. Other images or representations in the brain are involved in regulating such emotional responses. They help us control emotional responses and the behaviors they inspire using different chemicals.
Cultural representations such as stories are projections of such internal mental representations, and often, they have a regulatory function. They teach us to control behavior such as violence. One of the first long works of literature in the West—Homer’s Iliad—contains many stories, and one is about disobedient children. The children of Jove, the father god, insist on getting involved in human affairs, even when their father tells them not to. The result is disaster for the humans the disobedient children support. The story infers that it is better to obey parents, especially if they happen to be gods (as most parents are, of course).
Moral instructions acquired from literature, religious institutions, and schools are examples of mental representations that help us regulate behavior. When I was growing up, “beat swords into plowshares,” a phrase from the Jewish prophet Isaiah, was still a vibrant tool for guiding behavior some 3,000 years after Isaiah’s death. It had been placed in a niche storage locker for later retrieval by young people like me.
Like the images of angry faces, mental representations such as “beat swords into plowshares” or moral stories such as the Iliad inspire chemical changes in our brain. Reading makes us more empathetic, a neuronal and a neurochemical activity. And the thought of being generous to others rather than being violent towards them—of beating swords into plowshares—summons the neuropeptides oxytocin and endorphin that issue rewards to our brain.21 Over time, our brains become so used to receiving those rewards that the genes governing them such as COMT are affected. As more nonviolent behavior elicits more hormonal rewards, the supply of neuropeptides is depleted. More neuropeptides are called for, putting a strain on COMT. It adjusts to keep up. Variants of COMT such as Val158Met emerge that assure there are enough doses of endorphin available to attach to generous actions rather than to violent behavior. In a sense, the brain trains itself to evolve. It does so by using chemical mathematical modelling to keep the cerebral store shelves stocked with candy.
It is not at all farfetched to imagine our brains changing physiologically as a result of training or experience. Musicians, mathematicians, and London cab drivers all have this in common: the morphology of their brains was altered by repeated learning.
Processes like these are what Pinker has in mind when he argues that a humanitarian turn occurred in human life. Mental representations can change our biology because they are already in charge of regulating emotional responses that are based in neurochemical reactions. As a result, therapeutic cultural ideas and norms that promote nonviolent behavior affect not just ideology but also physiology (or to be more specific, neuropharmacology). A cultural change such as a humanitarian turn is not merely representational and not just a matter of better ideas and improved norms. It is a different way of activating or attenuating neurochemical processes that have genetic consequences. The humanitarian turn was also a biochemical turn, and it was likely also an evolutionary turn." (pp.9-11)
"Another way of accounting for the diminishment of violence, then, would be to say that improved mental representational abilities, when projected into the niche environment in the form of laws, norms, and ethical ideas, acted on our ancestors and changed the neurochemistry of the brain and the gene regulatory mechanisms that govern it, resulting in increased down-regulation of gene expression that inspired violence. So long as the niche prompts to that genetic action are in place, we will continue to enjoy less violence in our lives. But if those prompts disappear—as they did at the end of the Roman Empire—we can expect a reappearance of large-scale violent behavior.
Or not. The possibility exists that the hundreds of years of conditioned learning to be less violent have so altered the operation of our genes that they would continue to program less-violent behavior even in the absence of sustained niche support. This book is about such possibilities.
Jablonka and Lamb propose one other model of evolution. Many organisms are characterized by phenotypic plasticity. They assume different physical forms. As some organisms develop from gamete to adult, for example, they change morphology—pupa, larva, adult. Other organisms give rise to more than one phenotype. Certain grasshoppers are brown in one setting and green in another— despite having just one genotype. To grasp the implications of such phenotypic plasticity, imagine a White racist getting into their truck and driving across town to a Black neighborhood—where he emerges from his truck as a Black person. Unfortunately, not all polyphenism is so politically correct.
Plasticity is a common way for organisms to cope with environmental adversity. Some animals shed brown for white coats in winter, for example. Certain species of plants grow broad leaves if there is insufficient moisture to maintain life with narrow leaves. Such plasticity can affect the germ-line cells that pass on genetic information from parent to offspring, according to Jablonka and Lamb. Phenotypic plasticity means germ-line genes are more mutable. The ability of genes to generate multiple phenotypes makes genetic change more likely.
Indeed, such evolvability may be an acquired adaptive trait of certain organisms, and humans may be one of them. Our species has numerous phenotypes that range behaviorally from extreme Left to extreme Right. We resemble grasshoppers who are one color while alone and another when in large groups. In rural settings, we are more likely to be conservative, while urban settings encourage greater leftism because more contact with ethnic others reduces prejudice and encourages tolerance. Moreover, leftists are distinguished from rightists by their own version of phenotypic plasticity. They change behavior more readily than rightists in response to changing environmental signals. Such responsiveness resembles the phenotypic plasticity evident in plants and animals that change form when their environment changes. If Jablonka and Lamb are correct, such plasticity should encourage evolvability. And indeed, leftists seem to have evolved a greater ability to control violence. The human genome now generates phenotypes such as cognitive control over archaic behavior that are heritable." (pp.11-12)
"The various ways that evolution occurs is a topic of debate. According to the standard model of evolution, single nucleotide polymorphisms account for all evolutionary change. Evolution occurs when a random polymorphism accidentally produces an adaptive trait. If the trait and the gene variant benefit from positive selection, they become fixed. With each new generation, the frequency of the variant increases. Ultimately, it sweeps through the entire population and displaces its parent gene—much as the variant of APSM that makes our brain cases larger has done over the past 6,000 years.
The standard model works best in a limited population that is either homogenous in its mating practices like Orthodox Jews or isolated geographically like Tibetans. Certain gene variants associated with cognition have attained positive selection in Asia alone and do not appear in western populations. The positive selection of a trait for a global population of humans is harder to imagine, and indeed, large selective sweeps have been rare in recent human evolution. A population spread over the globe is less likely to experience hard sweeps.
New evolutionary theorists such as Jablonka and Karen West-Eberhard offer alternatives to the standard model of genetic evolution that account for the paucity of classic selective sweeps. The standard model is designed to avoid Lamarckism. Lamarck thought a giraffe stretched its neck to reach higher fruit and passed on its longer neck to offspring who stretched their necks even more—eventually achieving homeostasis with the environment and giving giraffes their defining anatomy. The organism’s interaction with the environment modified the giraffe’s genes.
Two aspects of Lamarckism were deemed doubtful by proponents of the evolutionary synthesis. One held that the phenotype—even the cell—rather than the gene, is the agent of evolutionary change. The other proposed that the interaction of organism and environment can cause evolution; genes are modified by an organism’s engagement with the world around it. The standard model corrected these “mistakes” by depicting evolution in strictly genotypic terms. Accidental changes to nucleotide sequences independent entirely of an organism’s engagement with its ambient world account for all evolution. And genomic change, not changes in how genes are epigenetically regulated at the phenotypic level or transformed by phenotypic behavior, is the motor of evolution.
These corrections did not account for the rapidity with which some genetic changes can occur—seemingly in response to environmental information. Random polymorphisms can take a long time to attain sufficient frequency to become fixed. Yet rapid evolutionary change is a common occurrence. Influenza is so persnickety because it evolves so rapidly.Moreover, non-selective forces such as gene conversion, which accelerates the rate of substitutions in gene combination, contribute to evolution in a process distinct from positive selection for single-nucleotide polymorphisms. Evolution seems to disobey its own rules fairly frequently.
According to the new evolutionary theories, genes are not sequestered from the environment. They can be changed by the situation in which they find themselves, and such change can occur rapidly.26 An ability to adapt to changing life circumstances is an inherited trait in some organisms, according to Jablonka and Lamb, and the ability to engage in rough guesses regarding what mutations are needed to survive seems to be an evolutionary innovation. Some genetic variation seems to be in direct response to the stressful conditions in which the organism finds itself because the responsive gene activity is in precisely the regions most affected by stress. For example, the three human body regions most affected by positive selection are the gastric system, the immune system, and skin—all three of which are distinguished by high levels of interaction with environments. The new evolutionary theories argue that environmental influence can change how genes work. If the stress and the response to it are consistent, they can result in a re-patterning of the genome, according to West-Eberhard." (pp.12-13)
-Michael Ryan, The Genetics of Political Behavior. How Evolutionary Psychology Explains Ideology, Routledge, 2021, 191 pages.
