Tag Archives: Evolution

Forced Birth from the Perspective of Evolutionary Psychology

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Evolutionary psychology, according to the Stanford Encyclopedia of Philosophy, “is one of many biologically-informed approaches to the study of human behavior”:

Along with cognitive psychologists, evolutionary psychologists propose that much, if not all, of our behavior can be explained by appeal to internal psychological mechanisms. What distinguishes evolutionary psychologists from many cognitive psychologists is the proposal that the relevant internal mechanisms are adaptations—products of natural selection—that helped our ancestors get around the world, survive and reproduce.

Two evolutionary psychologists argue that the real reason people oppose abortion (i.e. insist that pregnant women give birth) is that they find casual sex threatening:

It’s common to hear religious, political and other ideologically driven explanations – for example, about the sanctity of life. If such beliefs were really driving anti-abortion attitudes, though, then people who oppose abortion might not support the death penalty (many do), and they would support social safety net measures that could save newborns’ lives (many don’t).

The evolutionary coin of the realm is fitness – getting more copies of your genes into the next generation. What faraway strangers do presumably has limited impact on your own fitness. So from this perspective, it is a mystery why people in Pensacola care so strongly about what goes on in the bedrooms of Philadelphia or the Planned Parenthoods of Los Angeles.

The solution to this puzzle – and one answer to what is driving anti-abortion attitudes – lies in a conflict of sexual strategies: People vary in how opposed they are to casual sex. More “sexually restricted” people tend to shun casual sex and instead invest heavily in long-term relationships and parenting children. In contrast, more “sexually unrestricted” people tend to pursue a series of different sexual partners and are often slower to settle down.

These sexual strategies conflict in ways that affect evolutionary fitness.

The crux of this argument is that, for sexually restricted people, other people’s sexual freedoms represent threats. Consider that sexually restricted women often get married young and have children early in life….

Other women’s sexual openness can destroy these women’s lives and livelihoods by breaking up the relationships they depend on. So sexually restricted women benefit from impeding other people’s sexual freedoms. Likewise, sexually restricted men tend to invest a lot in their children, so they benefit from prohibiting people’s sexual freedoms to preclude the high fitness costs of being cuckolded [and their wives having other men’s children].

According to evolutionary social science, restricted sexual strategists benefit by imposing their strategic preferences on society – by curtailing other people’s sexual freedoms.

How can restricted sexual strategists achieve this? By making casual sex more costly.

For example, banning women’s access to safe and legal abortion essentially forces them to endure the costs of bearing a child. Such hikes in the price of casual sex can deter people from having it….

No one would argue this is a conscious phenomenon. Rather, people’s strategic interests shape their attitudes in nonconscious but self-benefiting ways – a common finding in political science and evolutionary social science alike.

An evolutionary perspective suggests that common explanations are not the genuine drivers of people’s attitudes – on either side of the abortion debate.

In fact, people’s stated religious, political and ideological explanations are often rife with awkward contradictions. For example, many who oppose abortion also oppose preventing unwanted pregnancy through access to contraception.

From an evolutionary perspective, such contradictions are easily resolved. Sexually restricted people benefit from increasing the costs of sex. That cost increases when people cannot access legal abortions or prevent unwanted pregnancy.

An evolutionary perspective also makes unique – often counterintuitive – predictions about which attitudes travel together. This view predicts that if sexually restricted people associate something with sexual freedoms, they should oppose it.

Indeed, researchers have found that sexually restricted people oppose not only abortion and birth control, but also marriage equality, because they perceive homosexuality as associated with sexual promiscuity, and recreational drugs, presumably because they associate drugs like marijuana and MDMA with casual sex. We suspect this list likely also includes transgender rights, public breastfeeding, premarital sex, what books children read (and if drag queens can read to them), equal pay for women, and many other concerns that have yet to be tested.

No other theories we are aware of predict these strange attitudinal bedfellows.

This evolutionary perspective can also explain why anti-abortion attitudes are so often associated with religion and social conservatism.

Rather than thinking that religiosity causes people to be sexually restricted, this perspective suggests that a restricted sexual strategy can motivate people to become religious. Why? Several scholars have suggested that people adhere to religion in part because its teachings promote sexually restricted norms. Supporting this idea, participants in one study reported being more religious after researchers showed them photos of attractive people of their own sex – that is, potential mating rivals….

There are multiple answers to any “why” question in scientific research. Ideological beliefs, personal histories and other factors certainly play a role in people’s abortion attitudes.

But so, too, do people’s sexual strategies.

This evolutionary social science research suggests that restricted sexual strategists benefit by making everyone else play by their rules. And just as Justice Thomas suggested when overturning Roe v. Wade, this group may be taking aim at birth control and marriage equality next.

Unquote.

I don’t know how applicable this explanation of forced birth attitudes is, but it sounds like a factor. One way to test the idea is to consider whether those who favor forced birth feel the same way when they have relationships with the woman who’s pregnant. Do anti-abortion men feel different if it’s their wife or daughter who’s pregnant? What if the wife is pregnant by another man? Do anti-abortion women sometimes decide they really don’t want a child or one more? My guess is that conservative opponents of abortion are much more accepting of abortion if the pregnancy is close to home and/or they don’t feel threatened by the sex involved (the example making news now is the Republican running — very badly — for the Senate in Georgia).

This Isn’t What We Need, But Nature Isn’t Asking Us

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As Omicron declines around much of the world, scientists are watching a new variant that’s even more contagious. So far, they don’t think it will have much effect on countries like the US that have already passed their Omicron peak. But this development reminded me of a recent book: Rob Dunn’s A Natural History of the Future: What the Laws of Biology Tell Us about the Destiny of the Human Species. From a NY Times review:

Levees surround us. Yes, some hold back rivers that strain against their embankments. But others hold back diseases, which are ready to saturate and overwhelm the fragile walls of antibiotics we’ve erected. And sometimes levees fail. The metaphor extends beyond epidemiology. Nature ceaselessly advances, trespasses, embarrasses our every effort to keep it at bay, and ultimately bursts through. Its rivers will not be contained.

In A Natural History of the Future, the ecologist Rob Dunn sketches an arresting vision of this relentless natural world — a world that is in equal measures creative, unguided and extravagant. Fog a tree with pesticides and watch new beetle species tumble from the canopy by the hundreds, a “riot of unnamed life.” Chlorinate your water and, though you might wipe out most parasites, you’ll soon bedew your shower head with chlorine-resistant mycobacteria. Make a world fit for bedbugs, then try to kill them with chemicals, and you’ll end up — not in a world without bedbugs, but one in which they’ve “evolved resistance to half a dozen different pesticides.”

Life is not a passive force on the planet, and much as we might presume to sit in judgment of Creation — even sorting species by their economic value to us — we live on nature’s terms. The sooner we recognize this, Dunn argues, the better.

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As humans retreat into more and more sanitized spaces, and our homes become spotless, Febrezed bunkers of sterility, we’ll increasingly find that we’ve not only failed to eradicate our microbial opponents, we’ve actually helped create new, more virulent forms of them.

Enter the terrifying “megaplate” experiment, carried out by researchers at Harvard. In it, E. coli is made to grow across what is essentially a giant petri dish, one partitioned into sections laced with increasingly lethal doses of antibiotics. In the final stage of the megaplate, the bacteria meet a concentration of antibiotics many thousands of times higher than that which can kill your garden-variety E. coli. Even so, at the rate of “one mutation per billion divisions,” the bug evolves, casually crossing the entire plate, even the almost impossibly lethal barrier at the end, slipping through the antibiotic revetments as surely as water through a crumbling dike. And in only 10 days.

“I show it in talks,” Dunn writes of a video of the experiment. “It makes people quiet. It is what Kant called the horrifying sublime.”

The experiment can be run again, and again it will take about 10 days. What goes for E. coli scales up to agricultural pests, only temporarily inconvenienced by new pesticides until they evolve around them. While ecology is sometimes regarded as one of the squishier sciences, these kinds of eventualities begin to point to something like a set of laws underlying it all. These laws — though lacking the bedrock status of the laws of physics — can sometimes be nearly as predictive. If we want to know what’s coming, then, we would be well advised to familiarize ourselves with them, Dunn argues. To that end, his book functions as a helpful crash course in ecology and, as the title implies, an augur of sorts.

The law of the niche, for instance, predicts that many hapless species will fail to track their habitats on our warming world and will go extinct (think snails marooned on quickly shrinking islands). Others, however, will be cast about the face of the earth as their climate niche expands, and will flourish. Most concerning, perhaps, Aedes is coming. Just as epidemiologists warned for years that a pandemic was not merely possible but inevitable, ecologists now warn us of the looming mosquito heyday as we warp the climate. Key to this warning is the choice of modal verb: It’s not that these tropical pests “could” establish themselves in much of the Southern United States if we’re not careful, but rather that they “will.” And they will carry with them “some complex mix of the dengue virus and the yellow fever virus, but also the viruses that cause chikungunya, Zika fever and Mayaro.”

While it might not surprise us to read that mosquitoes have a niche that affects their distribution on the planet, it might be more difficult to recognize that we humans do as well. We are animals after all, and can be studied as such by ecologists. Even with the spread of air-conditioning, and all the creature comforts afforded by burning fossil fuels by the gigaton, we still mostly inhabit the same shockingly narrow band of the globe that we have for millennia. But as we push the climate beyond the norms of the past three million years we will hit the hard limits of physiology. And as the familiar rhythms of the seasons grow more syncopated and strange, some swath of our range will be increasingly foreclosed, to God knows what geopolitical effect. Many of us will have to move.

Along this unsettling journey into the future, the mood is leavened here and there by oddities, which Dunn dusts off like the docent of a strange natural history museum. We learn that the Taung child, one of the earliest hominins known to science, was eaten by eagles. We learn that the yeasts that make beer come from the bodies of wasps. That when humans spread out into new landmasses our “face mites diverged.” The impression all this arcana leaves with the reader is that we live in a much weirder, more disorienting world than we tend to appreciate.

We simplify this chaos, this riot of life, at our peril. We hoist plants from their natural context, consign them to vast monocultures, then act surprised when the rest of nature conspires to tear them down. We panic when bees fail to submit to the rote demands of industrial agriculture. But if simplifying nature is the cause of so many modern ills, then Dunn’s policy prescription, conversely, comes down to one simple dictum: Diversify. Diversify the microbes in your intestines, the crops in your fields, the plants in your watershed, the research in your grant proposals. Recruit the forests to filter your water. Let a trillion microbial flowers bloom.

This strategy works because nature is cleverer than us. The science historian George Dyson once described evolution itself as a kind of computational process that solves problems like how to swim, and how to fly. But the new problems we’ve given it to solve are ill considered, and the solutions it produces often undesirable. We dare life to overtop the levees of pesticides, herbicides, antibiotics; to overrun the concrete outcrops of cities, insinuate itself in the cracks of human society and pick the locks of our immune system. If we wipe out charismatic megafauna, of the sort that graces the brochures of conservation nonprofits, fine, nature seems to say, a florescence of rats and crows it is. Want to live in modular outcrops of steel, glass and cement, fed by rivers of pavement spanning thousands of miles? Very well, this will be a migration corridor for mice, pigeons and disease. They represent life too, after all, and the planet gives not a whit if it’s inhabited by lions or cockroaches. There are now beetles that consume only grains, mosquitoes that live only in the London metro. “Evolution creates,” Dunn writes, “and acts of creation are never complete.”

Dunn’s account leaves an overwhelming impression of fecundity, growth, adaptation. But this isn’t a naïvely rosy vision of the future like some contrarian tracts on the resilience of nature in the Anthropocene. From a human perspective this will be an impoverished world, and many of Dunn’s warnings are concrete and sobering. . . .  The rivers are rising.

It Looks Like Evolution Doesn’t Work the Way We Thought!

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In five words: mutations are not always random. This is according to a study reported by the University of California, Davis:

A simple roadside weed may hold the key to understanding and predicting DNA mutation, according to new research from UC Davis, and the Max Planck Institute for Developmental Biology in Germany.

The findings, published today in the journal Nature, radically change our understanding of evolution and could one day help researchers breed better crops or even help humans fight cancer.

Mutations occur when DNA is damaged and left unrepaired, creating a new variation. The scientists wanted to know if mutation was purely random or something deeper. What they found was unexpected.

“We always thought of mutation as basically random across the genome,” said Grey Monroe, an assistant professor in the UC Davis Department of Plant Sciences … “It turns out that mutation is very non-random and it’s non-random in a way that benefits the plant. It’s a totally new way of thinking about mutation.”

Researchers spent three years sequencing the DNA of hundreds of Arabidopsis thaliana, or thale cress, a small, flowering weed considered the “lab rat among plants” because of its relatively small genome comprising around 120 million base pairs. Humans, by comparison, have roughly 3 billion base pairs. 

“It’s a model organism for genetics,” Monroe said.

Work began at Max Planck Institute where researchers grew specimens in a protected lab environment, which allowed plants with defects that may not have survived in nature be able to survive in a controlled space.

Sequencing of those hundreds of Arabidopsis thaliana plants revealed more than 1 million mutations. Within those mutations a nonrandom pattern was revealed, counter to what was expected.

“At first glance, what we found seemed to contradict established theory that initial mutations are entirely random and that only natural selection determines which mutations are observed in organisms,” said Detlef Weigel, scientific director at Max Planck Institute . . . 

Instead of randomness they found patches of the genome with low mutation rates. In those patches, they were surprised to discover an over-representation of essential genes, such as those involved in cell growth and gene expression.

“These are the really important regions of the genome,” Monroe said. “The areas that are the most biologically important are the ones being protected from mutation.”

The areas are also sensitive to the harmful effects of new mutations. “DNA damage repair seems therefore to be particularly effective in these regions,” Weigel added.

The scientists found that the way DNA was wrapped around different types of proteins was a good predictor of whether a gene would mutate or not. “It means we can predict which genes are more likely to mutate than others and it gives us a good idea of what’s going on,” Weigel said. 

The findings add a surprising twist to Charles Darwin’s theory of evolution by natural selection because it reveals that the plant has evolved to protect its genes from mutation to ensure survival.  

“The plant has evolved a way to protect its most important places from mutation,” Weigel said. “This is exciting because we could even use these discoveries to think about how to protect human genes from mutation [including mutations that cause disease like cancer].

“Our discoveries yield a more complete account of the forces driving patterns of natural variation; they should inspire new avenues of theoretical and practical research on the role of mutation in evolution,” the paper concludes.

Unquote.

Nevertheless, random mutations do occur and presumably led to some mutations not being random, i.e. the plant above evolved via random mutation to protect itself with mutations that aren’t.

Children of Time by Adrian Tchaikovsky

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This is a remarkable science fiction novel. It’s quite a story, quite a work of imagination.

What happens is that human beings have been screwing up the Earth to the point that it’s becoming uninhabitable. One response has been to try to create Earth-like conditions on planets in distant solar systems. It’s hoped that these planets will eventually become new homes for humanity.

The terraforming work on one such planet is sabotaged at the last moment. This leads to an enormous unintended consequence: some of the planet’s spiders rapidly evolve, becoming bigger, smarter and much more sociable than the spiders back on Earth.

Before the Earth becomes uninhabitable, giant spaceships are launched with thousands of people aboard. Most of the passengers are stored away as “cargo”, hibernating in an unconscious state, waiting to be resuscitated when their ships finally reach inhabitable worlds, many years in the future.

Throughout the book, the author switches back and forth between what’s happening to the spiders on their planet and what’s happening to the people in one of the spaceships. I felt closer to the people, but the author does a wonderful job explaining things from the perspective of the spiders. As you’d expect, the two species eventually meet.

Somebody is supposedly trying to turn Children of Time into a movie. It really deserves a TV series, possibly with multiple seasons. The author has also published a sequel, Children of Ruin. It’s probably remarkable too.

Other Minds: The Octopus, the Sea and the Deep Origins of Consciousness by Peter Godfrey-Smith

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Peter Godfrey-Smith is an Australian professor of philosophy who has spent many hours scuba-diving in order to observe the behavior of octopuses and cuttlefish. The book is an attempt to trace the evolution of mental activity from its earliest beginnings hundreds of millions of years ago, when bacteria began reacting to their surroundings. The author believes that mind and consciousness didn’t suddenly spring into existence; they developed gradually through millions of years. But he admits that nobody knows for sure.

Neither do we know what it’s like to be an octopus. We don’t even know for certain that it’s like anything at all. Maybe octopuses go about their business without feelings or anything like consciousness. Godfrey-Smith, however, argues that it’s reasonable to believe that creatures of many sorts feel pain when they are injured. But where to draw the lines (if there are any lines) between bacteria that simply react, animals that feel pain and creatures like us who are self-conscious is a mystery.

Octopuses are especially interesting because our common ancestors lived about 500 million years ago. Octopuses developed complex nervous systems, arranged differently than ours, independently from most other animals, including us. That means, in Godfrey-Smith’s words, “meeting an octopus is, in many ways, the closest we’re likely to get to meeting an intelligent alien”. It’s really too bad that they can’t tell us what it’s like to be them.

I wish the book ended with a summation of the author’s conclusions. I do remember the idea that nervous systems first evolved in order to respond to a living thing’s surroundings, and then to monitor its internal states and control its movements. And I remember a lot about the interesting behavior of octopuses and their close relations, cuttlefish. But I can’t say I came to any solid conclusions about the deep origins of consciousness. If the author reached any conclusions, he should have reminded his readers what they were.