In the mid-1800s, Claude Bernard – the “father of experimental physiology” – began a series of experiments to create carnivorous rabbits.
Don’t worry: Bernard wasn’t cultivating predatory beasts like the angry rabbit in Monty Python and the Holy Grail. At first he was simply starving animals until their acidic urine indicated that they’d begun to consume their own flesh as fuel. Deprived of calories, any animal will metabolize its own muscle.
But Bernard went further. As he describes in An Introduction to the Study of Experimental Medicine (translated by Henry Copley Greene), Bernard felt that:
“A carnivorous rabbit had to be experimentally produced by feeding it with meat …”
“I had rabbits fed on cold boiled beef (which they eat very nicely when they are given nothing else). My expectation was again verified …”
“To complete my experiment, I made an autopsy on my animals, to see if meat was digested in the same way in rabbits as in carnivora. I found, in fact, all the phenomena of an excellent digestion in their intestinal reactions …”
This was a strange experiment. Claude Bernard did make a novel discovery, but I don’t think the gains were commensurate with the cost.
Bernard, however, was proud of his willingness to inflict pain for the sake of science. He had a reputation for live dissections of unanesthetized dogs; his spouse called him a monster, divorced him, and created France’s first animal welfare organization.
By all outward appearances, Bernard was unperturbed. He told his friends and colleagues that he’d only married that woman for her money, anyway, which he’d needed to build his first laboratory. By the time she left, she was of no further use to him. And he was disinterested in her “fashionable” morality.
In An Introduction to the Study of Experimental Medicine, Bernard writes that,
“A physiologist is not a man of fashion, he is a man of science, absorbed by the scientific idea which he pursues: he no longer hears the cry of animals, he no longer sees the blood that flows, he sees only his ideas and perceives only organisms concealing problems which he intends to solve.”
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Claude Bernard tortured animals, disdained Charles Darwin’s theory of evolution, and loathed the introduction of statistics into biological research. Still, the conclusion of Bernard’s rabbit experiment is correct.
Herbivores can digest meat.
And this transition – an herbivore switching to a meat-based diet – is far more common than its opposite. Plants are much more difficult to eat!
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Most species that we think of as herbivores will occasionally eat meat. Cows consume chickens, mice, dead rabbits (especially if the cows are mineral deficient, such as the experimental herds intentionally fed a low-phosphorous diet in the 1990s). Squirrels raid nests to eat baby birds. Pandas will eat roadkill if they can’t find enough bamboo.
After all, another animal’s body provides the full compliment of nutrients that an animal needs – it’s much easier to live as a mere meat refurbisher than to create your own animal body from scratch!
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In a research article published in 2019, “Evolution of Diet Across the Animal Tree of Life,” Christian Roman-Palaclos, Joshua Scholl, and John Wiens speculate that the very first animals were carnivores. They write that:
“Remarkably, our results suggest that many carnivorous animals alive today may trace this diet through a continuous series of carnivorous ancestors stretching back for >800 million years.”
Their data don’t actually support this claim. Roman-Palaclos, Scholl, and Wiens categorized the diets (herbivorous, carnivorous, or omnivorous) of a wide range of animal species and found that a statistical model in which the first multicellular animals consumed other heterotrophs would be mathematically parsimonious. Historically, it would take fewer genetic changes to produce our world if herbivory had evolved independently many times over.
But evolution tends to be quite rapid when organisms encounter an empty ecological niche, which is why we see sudden increases in diversity during periods following mass extinctions (like the “Cambrian explosion”) and when animals reach new islands. And we know that multicellular life arose multiple times – at the very least, happening independently in both plants and animals.
The earliest multicellular animals were probably simple aggregates of cells that failed to separate after dividing. Even after genes could cause intentional multicellular development, these early animals were probably blobby things that pursued the same diets as their single-celled precursors.
All told, many of the assumptions made by Roman-Palaclos, Scholl, and Wiens seem dubious at best.
And yet. It probably would have been easier for earliest animals to eat other heterotrophs than to eat autotrophs. Single-celled protists already liked to eat the autotrophs, so most autotrophs had defenses. The autotrophs might be toxic; their tasty molecules were hidden behind indigestible cell walls. If the first multicellular animal gobbled these up, it would’ve gotten such a bellyache!
Except, right. The first multicellular animal didn’t have a belly.
It would’ve gotten such a lysosome-ache!!
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In more recent evolution, herbivorous mammals often developed pretty major adaptations to accompany their diet. For instance, herbivores typically have more complicated teeth than carnivores – by chewing their food, herbivores can rupture a plant’s cell walls to access the nutrients inside. And instead of stealing a full compliment of essential amino acids and vitamins from another animal, an herbivore has to synthesize these inside its body. Biosynthesis of Vitamin B12 is pretty tricky – my cells certainly can’t do it. Can yours?
A human whose body contained only human cells could barely digest anything, and certainly not plants. Indeed, most human babies begin life this way – as wholly human. Newborns seem to have very few bacteria inside their bodies, and it’s difficult for newborns to digest anything other than milk.
Soon after birth, though, humans acquire a wide range of passengers. On the surface of our skin and throughout our intestines, we harbor bacteria, many of which are essential for our health. Our passengers interact directly with our brains: certain gut microbes make exercise more pleasurable; other gut microbes are so closely linked with mood & mental wellness that researchers are exploring ways to use them therapeutically.
Without the help of the bacteria who build empires inside our bodies, we would be miserable – achy, asthmatic, bloated, and mentally unsound. And also, yes – without their help, we could not eat plants.
How fortunate that we are not alone!
Header image credit: Darryl Leja for the National Human Genome Research Institute’s photostream on flickr.
Like many people, I have a weak grasp on long times. My family often visits a nearby pioneer reenactment village where the buildings and wooden gearworks of its water-powered corn mill are about two hundred years old; I feel awed. In Europe, some buildings are a thousand years old, which sounds incredible to me.
These are such small sips of evolutionary time.
Humans have roamed our world for hundreds of thousands of years. Large dinosaurs ruled our planet for hundreds of millions of years. Animals whom we’d recognize as Tyrannosaurus rex prowled for the final 2.5 million years of that, with their last descendants dying about 66 million years ago.
My mind struggles to comprehend these numbers.
I found myself reflecting on this after a stray remark in Oded Galor’s The Journey of Humanity: The Origins of Wealth and Inequality: “Why is such a powerful brain so rare in nature, despite its apparent advantages?”
Galor’s question seems reasonable from the vantage of the present. We live on a planet where 96% of the mammalian biomass is either our own species or prey animals we’ve raised to eat. The total mass of all surviving wild dinosaurs – otherwise known as “birds” – is less than a thirtieth the mass of humans. We’ve clearly conquered this world. Our dominance is due to our brains.
And this moment – right now! – feels special because we’re living through it. From a geological or evolutionary perspective, though, the present is a time much like any other. If we represent the total lifespan of our sun as a 24-hour day (which is much more sensible than representations with the present moment at the end of the day), the current time would be 10:58 a.m., and our sun will become so hot that it boils away all our planet’s liquid water at 7:26 p.m. Between now and then, though, we have a whole workday’s time for life to continue its beautiful, chaotic evolutionary dance. Perhaps quite soon – maybe just a million years from now, or 10 million, which is less than two minutes of our total day – the descendants of contemporary parrots, crows, or octopuses could become as intelligent as contemporary Homo sapiens.
As a human, I’m biased toward thinking that parrots and crows would have a better chance than octopuses – after all, these birds face a similar evolutionary landscape to my own ancestors. They’re long-lived, social species that invest heavily in childcare, are anatomically well-suited for tool use, and face few risks from predators.
Or rather, parrots would face few risks if humans weren’t around. Unfortunately them, a voracious species of terrestrial ape is commandeering their homeland and kidnaps their young to raise as pets. But crows can thrive in a human-dominated landscape – some crows even use our cars as tools, cracking nuts by placing them in urban crosswalks then retrieving their snack after the light turns red.
Octopuses, however, are short-lived and antisocial. They’re negligent parents. Their brief lives are haunted by nightmarish predators. And yet. Some octopuses are already quite intelligent; their intelligence appears to confer a reproductive advantage (if only by virtue of survival); their bodies are well-suited for tool use. Certain types of tools, like flaked stone, would be more difficult to create underwater, but many octopuses are capable of brief sojourns into open air. So I wouldn’t rule them out. Sometimes evolution surprises us – after all, the world has a lot of time to wait.
Which means that powerful brains like ours might not be rare in the future. Especially if our species does something stupid – like engaging in nuclear war, succumbing to global pandemic, or ruining crop yields with climate change – and the animal kingdom’s future intelligentsia don’t have to compete with 8 billion Homo sapiens for space and resources.
Also, it’s surprisingly difficult to assess whether powerful brains like ours were rare in the past. Intelligent, tool-crafting, fire-wielding, language-using species have gone extinct before – consider the Neanderthal. Our own ancestors nearly went extinct during past episodes of climate change, like after a volcanic eruption 70,000 years ago. And even if some species during the age of dinosaurs had been as intelligent as modern humans, we might not recover much evidence of their brilliance.
Please note that I’m not arguing that Tyrannosaurus rex wove baskets, wielded fire, or built the Egyptian pyramids. For starters, the body morph of T-Rex is ill-suited for tool use (as depicted in Hugh Murphy’s T-Rex Trying comics). But simply as a thought experiment, I find it interesting to imagine what we’d see today if T-Rex had reached the same level of technological and cultural sophistication as humans had from 100,000 to 10,000 years ago.
If T-Rex made art, we wouldn’t find it. The Lascaux paintings persisted for about 20,000 years because they were in a protected cave, but as soon as we found them, our humid exhalations began to destroy them. Millions of years would crush clay figurines, would cause engraved bone to decompose.
If T-Rex crafted tools from wood or plant fibers, we wouldn’t find them. We can tell that ancient humans in the Pacific Northwest of North America caught an annual salmon harvest by analyzing radioactive isotopes, but we’ve never found evidence of the boats or nets these ancient people used. After a few more radioactive half-lives passed – much sooner than a million years – this would have become invisible to us.
If T-Rex crafted tools from stone, we’d find remnants, but they’d be difficult to recognize. Evidence for human tool use often comes in three types – sharp flakes (usually 1-3 inch blades used as knives or spear tips), a hammer (often just a big round stone), and a core (a hunk of good rock that will be hit with the hammer to knock knife-like flakes off its surface). We’re most likely to realize that a particular rock was a human tool if it’s near a human settlement or if it’s made from a type of sediment rare in the location where contemporary archaeologists found it (which is why we think that an ancient primate took particular interest in the Makapansgat pebble).
Still, time is a powerful force. 66,000,000 years can dull the edges of a flake, or produce sharp rocks through mindless geological processes. It’s been difficult for archaeologists studying submerged sites in ancient Beringia – a mere 30,000 years old! – to know for certain whether any particular rock was shaped by human hands or natural forces. Other stone tools used by ancient humans look a lot like regular rocks to me, for example this 7,000-year-old mortar from Australia or these 9,000-year-old obsidian knives from North America. Ten million more years of twisting, compressing, and chipping might deceive even a professional.
And then there’s the rarity of finding anything from that long ago. Several billion T-Rex have tromped across the land, but we’ve only found as much as a single bone from a hundred of them. 99.999996% of all T-Rex vanished without a trace.
From those rare fossils, we do know that T-Rex brains were rather small. But not all neurons are the same. Work from Suzana Herculano-Houzel’s research group has shown that the number of neurons in a brain is a much better proxy for intelligence than the brain’s total size – sometimes a bigger brain is just made from bigger neurons, with no additional processing power. And the brains of our world’s surviving dinosaurs are made quite efficiently – “Birds have primate-like numbers of neurons in the forebrain.” **
We humans are certainly intelligent. And with all the technologies we’ve made in the past 200 years – a mere millisecond of our sun’s twenty-four hour day – our presence will be quite visible to any future archaeologists, even if we were to vanish tomorrow. But we do ourselves no favors by posturing as more exceptional than we are.
Animals much like us could have come and gone; animals much like us could certainly evolve again. Our continued presence here has never been guaranteed.
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** A NOTE ON NEURON COUNTS: many contemporary dinosaurs have brains with approximately 200 million neurons per gram of brain mass, compared to human brains with approximately 50 million neurons per gram of brain mass. A human brain has a much higher total neuron count, at about 80 billion neurons, than dinosaurs like African Gray Parrots or Ravens, which have about 2 billion neurons, but only because our brains are so much more massive. If the brain of a T-Rex had a similar composition to contemporary dinosaurs, it might have twice as many neurons as our own.
Of course, elephant brains also have three times as many neurons as our own — in this case, researchers then compare neuron counts in particular brain regions, finding that elephant brains have about a third as many neurons specifically in the cerebral cortex compared to human brains. For extinct species of dinosaurs, though, we can only measure the total size of the cranial cavity and guess how massive their brains would have been, with no indication of how these brains may have been partitioned into cerebellum, cerebral cortex, etc.
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Header image: a photograph of Sue at Chicago’s Natural History Museum by Evolutionnumber9 on Wikipedia.
The Supreme Court is considering whether to overturn the standing decisions from Roe v. Wade (1973) and Planned Parenthood v. Casey (1992). The majority opinions in those cases guaranteed … um, actually, quite little?
Soon, those opinions might guarantee even less!
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Justice Sonia Sotomayor is worried that the Supreme Court might lose its aura of legitimacy.
Justice Sotomayor said, “Will this institution survive the stench that [overturning Roe v. Wade would create] in the public perception that the Constitution and its readings are just political acts? I don’t see how it is possible.”
This is actually a major reason why Roe v. Wade wasn’t overturned previously. In a recent essay on Planned Parenthood v. Casey, ACLU legal director David Cole writes that “As the three then-recently Republican-appointed justices … warned in 1992, overruling Roe would do ‘profound and unnecessary damage to the Court’s legitimacy and to the Nation’s commitment to the rule of law.’ That is only more true today.”
And, look: I’m pro-choice. I would prefer for anti-abortion laws like those recently enacted in Texas and Mississippi to be revoked.
But also: the idea that our Supreme Court might lose some of its power makes me quite pleased!
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In our country, there are ostensibly three equal branches of government to balance each other.
Which sounds like a nifty design! Barstools often have three legs because any three points define a plane (unless they’re all on the same line), so three-legged stools are rarely tippy. Quite helpful when the sitter might be tipsy!
But something’s gone wrong with our government.
The recently-ritualized filibusterer system of our legislative branch that allows any proposal to be passively smothered, often by senators who represent fewer people than live in single neighborhoods of major cities. The post-9/11 domestic spying and drone strike assassinations from our executive branch. These are strange aberrations!
The worst offender, though, is probably our judiciary. Over many years, our Supreme Court justices have steadily commandeered more power, and the system is untenable.
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Unfortunately, our Supreme Court justices are incompetent.
This isn’t really their fault!
And I happen to think that several of them are clever, kind-hearted people. I really liked when Justice Sotomayor’s minority opinion for Utah v. Strieff included a reading list to help people who hadn’t noticed the lingering ramifications of institutional racism in our country.
That was grand!
But for our Supreme Court justices to form meaningful opinions about the whole range of cases that come before them, they should understand computers, artificial intelligence, psychology, sociology, economics, biology, medicine … and, they don’t.
To be nominated for a seat on the Supreme Court, a person instead needs to have specialized in our country’s adversarial system of law. Which means, due to time constraints, that they probably won’t have an adequate understanding of many vital subjects.
Worse, the one subject that they did specialize in – adversarial law – isn’t even helpful! Immersion in this style of thought probably makes people less suited to serve on the Supreme Court. As law professor Sarah A. Seo wrote in a recent essay on public defenders, “Adversarialism is not inherent to justice – it’s simply one way of administering it.”
Even if the adversarial arguments mattered – if, for instance, we lived in an alternate universe where the judges were such flexibly-minded people that they allowed themselves to be persuaded in court, that we couldn’t predict how they were going to vote well before any arguments had been presented – the idea of “justice” arising from competition instead of justice by collaboration is a foolish way to run a country.
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Often, people refer to Roe v. Wade in shorthand, suggesting that the decision guarantees a right to privacy, perhaps, or more specifically a right to abortion.
It doesn’t.
Instead, the majority opinion for Roe v. Wade says that “Though the State cannot override [the right to privacy, including a woman’s qualified right to terminate her pregnancy], it has legitimate interests in protecting both the pregnant woman’s health and the potentiality of human life, each of which interests grows and reaches a ‘compelling’ point at various stages of the woman’s approach to term.”
There are two conflicting rights, and the majority opinion is proposing a guideline for their balance. This is quite common. We balance people’s privacy against the state’s interest in preventing crime. We balance manufacturers’ desire to pollute with other people’s desire to breathe clean air or drink clean water.
In Roe v. Wade, the justices were balancing women’s bodily autonomy against the state’s interest in protecting the health of possible future citizens.
The justices concluded that: “For the stage subsequent to [fetal] viability the State, in promoting its interest in the potentiality of human life, may, if it chooses, regulate, and even proscribe, abortion except where necessary, in appropriate medical judgment, for the preservation of the life or health of the mother.”
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When conservative commentators describe Roe v. Wade as a terrible ruling, I’m inclined to agree with them.
Yes, the three new Supreme Court justices – the stolen seat, the attempted rapist, & the hypocritical election’s-eve appointment – would like to overturn Roe v. Wade. But they hardly even need to! The existing opinion already does so little to protect women’s rights!
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A large section of the ruling for Roe v. Wade discusses ancient attitudes toward abortion.
This discussion is markedly incomplete. Supreme Court justices simply don’t know enough to make their rulings! And there’s not a great solution to this, since very few possible groupings of nine people would include enough expertise to handle all the cases on a year’s Supreme Court docket.
Abortion has long been a common practice – healers and midwives in many cultures knew which local plants were arbotifacients. And any discussion of ancient attitudes toward abortion should also discuss infanticide.
Infanticide was common during recorded history. Based on studies of surviving hunter-gatherer cultures, we also have reason to suspect that infanticide was even more common in our species’s prehistory. In relatively recent times, if a baby was carried to term and then given up for adoption – perhaps left upon the doorstep or a church or monastery – there was significant risk of death. Amid high childhood mortality, a baby separated from the mother would face especially grim odds.
Compared to other primates, human mothers form emotional bonds to a child relatively late in development. Among our evolutionary cousins, it’s rare for a mother to allow any individual (not the baby’s father, not her own mother, not her other children) to even touch her baby. A full year might pass before the mother could bear the sight of her baby in another caregiver’s arms.
There are huge benefits that human mothers are less protective – shared child-rearing cements trust between adults, allows for our babies to be born earlier in biological development (essential given the size of our brains!), and leads to more attentive lifetime care.
Plus, this evolutionary history has made human babies so cute! Our offspring wouldn’t giggle and coo – behaviors that delight a potential caregiver – if they relied only upon irrevocable maternal love in order to survive. Chimpanzees are born cute – in their first few moments, they need to delight their mothers – but their tendency to giggle or mirror facial expressions fades within the first week or so. Unlike human babies, they aren’t constantly prepared to woo a new adult.
But human delay in attachment also made abortion and infanticide more acceptable to our species. In many hunter-gatherer societies, any child who could not be cared for would be abandoned. Other great apes are actually far more likely to care for a developmentally-disabled child than are human hunter gatherers.
In many societies, personhood wasn’t attained until age five or six, at which time a naming ceremony would be held. It was considered bad luck to name a child sooner, or to feel too attached before that date.
Of course, most families probably still did feel attached. There can be a stark difference between private affection and public nonchalance, a play act to ward off bad luck.
In terms of the rights at stake in Roe v. Wade, though, all these historical considerations are mostly irrelevant. Yes, that’s the science – findings from nature. But nature isn’t good or bad. Nature isn’t ethical. The natural world simply is, whereas ethics demands that we think about how the world should be. Reading the majority opinion for Roe v. Wade, it seems like these topics were introduced only to make the conclusion seem scientific or better reasoned.
In the end, the majority opinion is based solely on medical technology: the State can ban abortion at the age when a baby could survive outside a woman’s body.
Could survive.
Not would. And certainly not will.
Could survive.
“For the stage subsequent to viability the State … may proscribe abortion … “
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In Sex Robots and Vegan Meat, journalist Jenny Kleeman investigates several efforts to construct an artificial womb.
In an age when being a good parent means being as attentive as possible even before birth, we want better access to the babies growing inside pregnant women, better ways of measuring them and putting them under surveillance, so we can do the best for them even before they enter the world. Women’s bodies are almost getting in the way.
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Ultrasound images show how much female bodies are already seen as vestigial in reproductive medicine.
“I’ve been arguing for years, don’t show pictures of fucking developing fetuses unless you show the entire woman’s body,” [says Soraya Chemaly.]
“I understand people getting pregnant and being excited, but I’m the terrible feminist killjoy; I’m like, ‘Oh, that’s nice, why don’t we just make it bigger?’ Ultrasound was very deliberately developed to show the fetus as though it were a planet in a void, in a vacuum, in a container, in a jar. A wallpaper of blackness around it. It completely erases the woman whose body is generative.”
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For a human baby to be born, a parent must make an enormous gift. Feeding and protecting and creating the gestating fetus over many months.
Currently, there’s no other way.
Currently, it’s impossible to combine a sperm cell and an egg cell in the laboratory, create an embryo, then provide the necessary nutrients and environment for that embryo to develop into a fetus, a baby, a child.
Currently.
This would be a challenging project!
But not impossible.
Researchers will eventually be able to create a viable human child this way.
An act that would, per Roe v. Wade, instantly erase women’s rights.
Maybe this experiment would cost hundreds of millions of dollars. So what? For Supreme Court rulings, cost is irrelevant. They’ve made this clear in their decisions for many recent cases.
Our Supreme Court decided that anonymously-chartered corporations have as much right to free speech as individuals – as though they weren’t already privileged with more speech, since wealth can be used to purchase expensive advertisements, think tanks, unscrupulous academics.
Our Supreme Court decided that the police can legitimately spy on you with any technologies that are publicly available, even if these technologies – like infrared cameras to visualize your body through the walls of your home, or telescoping lenses to peer into your windows from a distance, or a steady helicopter to linger overhead and watch you from unexpected angles – are far outside the budgets (and therefore expectations) of most private citizens.
It’s quite convenient that the justices so often fail to notice people’s wealth! (Or lack thereof.) Abortion laws were never really intended to target wealthy people, anyway. Wealthy people could either travel out of state or pay off a doctor to certify that an abortion met “appropriate medical judgment for the preservation of the life or health of the mother.”
If researchers spent hundreds of millions of dollars to nurture one embryo into a viable human baby – in a laboratory anywhere around the world – then the principle of fetal viability cited in Roe v. Wade would allow states to outlaw all abortion. Even though the material facts of women’s lives would be unchanged.
This is, after all, the problem with trying to slap scientific justifications onto a philosophical argument. Whether or not women should have bodily autonomy is a philosophical question. I think that they should. Our steadily increasing technological prowess shouldn’t change that.
The world is complicated. There’s so much information out there, so much to know. And our brains are not made well for knowing much of it.
I can understand numbers like a dozen, a hundred. I can make a guess at the meaning of a thousand. Show me a big gumball machine and ask me to guess how many gumballs are in it, maybe I’ll guess a thousand, a few thousand.
But numbers like a million? A billion? A trillion? These numbers are important, I know. These numbers might be the population of cities, or of planets, or of solar systems. These numbers might be the ages of species or planets. These numbers might be how many stars are in the sky, or how many stars in the sky might harbor life.
These numbers don’t mean much to me.
I don’t think the problem is just my brain. I’m fairly good with numbers, relative to the average human. It’s been years since I’ve sat in a math class, but I can still do basic integrals and derivatives in my head.
Yet I can’t understand those big numbers. They don’t feel like anything to me.
So we make graphs. Charts. We try to represent information in ways that our meager human brains can grasp.
A good chart can be a revelation. Something that seemed senseless before is now made clear.
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An apocalypse is a revelation. The word “apocalypse” means lifting the veil – apo, off; kalyptein, conceal. To whisk away the cover and experience a sudden insight.
An illustration that depicts information well allows numbers to be felt.
Often, though, we illustrate information and we do it poorly.
The scientific method is gorgeous. Through guesswork, repetition, and analysis, we can learn about our world.
But science is never neutral. We impart our values by the questions we choose to ask, by the ways we choose to interpret the world’s ever-oblique answers.
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Geological time is often depicted as a clock. A huge quantity of time, compressed down into a 24-hour day. Often, this is done with the ostensible goal of showing the relative unimportance of humans.
Our planet has been here for a day, and humans appear only during the final two minutes!
Unfortunately, this way of depicting time actually overemphasizes the present. Why, after all, should the present moment in time seem so special that it resides at midnight on our clock?
The present feels special to us because we’re living in it. From a geological perspective, it’s just another moment.
Geologic textbooks invariably point out (almost gleefully) that if the 4.5-billion-year story of the Earth is scaled to a 24-hour day, all of human history would transpire in the last fraction of a second before midnight.
But this is a wrongheaded, and even irresponsible, way to understand our place in Time. For one thing, it suggests a degree of insignificance and disempowerment that not only is psychologically alienating but also allows us to ignore the magnitude of our effects on the planet in that quarter second.
And it denies our deep roots and permanent entanglement with Earth’s history; our specific clan may not have shown up until just before the clock struck 12:00, but our extended family of living organisms has been around since at least 6 a.m.
Finally, the analogy implies, apocalyptically, that there is no future – what happens after midnight?
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Timefulness is a lovely book, but Bjornerud does not present a corrected clock.
And so I lay in bed, thinking. How could these numbers be shown in a way that helped me to understand our moment in time?
I wanted to fix the clock.
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The first midnight is easy – the birth of our sun. A swirling cloud of gas condenses, heating as gravity tugs the molecules into more and more collisions. Nuclear fusion begins.
Gravity tugs molecules inward, nuclear explosions push them outward. When these are balanced, our sun exists. Twelve o’clock.
Two minutes later, our planet is born. Metal and water and dust become a big rock that keeps swirling, turning, as it orbits the sun. It’s warmed, weakly, by light from the sun – our star shone dimly then, but shines brighter and brighter every day.
Our sun earns low interest – 0.9% each hundred million years, hotter, brighter. But wait long enough, and a low interest is enough.
Someday, shortly before it runs out of fuel, our sun will be blinding.
By 12:18 a.m., there is life on Earth. We’ve found fossils that many billions of years old.
And at 7:26 p.m., there will be no more life. Our sun will have become so bright that its blinding light evaporates all the oceans. The water will boil so hot that it will be flung into space. The Earth will be a rocky desert, coated perhaps in thick clouds of noxious gas.
Currently, it’s 10:58 a.m.
The dinosaurs appeared 35 minutes ago. 9.5 minutes ago, all of them died (except the ancestors of our birds).
Humans appeared 1 minute ago.
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So, we have 3.5 billion years remaining – another 8.5 hours on our clock – before we have to migrate to the stars.
Humans certainly can’t persist forever. Empty space is stretching. Eventually, the whole universe will be dark and cold, which each speck of matter impossibly far from every other.
But our kind could endure for a good, long while. Scaled to the 24-hour day representing the lifespan of our sun, we still have another 300 years before the universe goes dark.
So many stories could fit into that span of time.
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It’s 10:58 a.m., and life on Earth has until 7:26 p.m.
Humans crept down from trees, harnessed fire, invented writing, and built rockets all within a single minute. Life moves fast.
Quite likely, life from Earth will reach the stars.
But it needn’t be us.
The dinosaurs were cool. They didn’t make it.
We naked apes are pretty cool, too. I love our cave drawings, art museums, psychedelic street art. Our libraries. But we’ve also made prodigious mounds of trash. We’re pouring plumes of exhaust into the sky as we ship giant flatscreen televisions from place to place.
We burn a lot of fuel for the servers that host our websites.
We humans aren’t the first organisms to risk our own demise by pumping exhaust into the atmosphere. The industrial revolution was fueled by ancient plants – our engines burn old sunlight. But many microbes are happy to eat old sunlight, too. These microbes also pump carbon dioxide into the air. They’ve warmed our planet many times before – each time the permafrost thawed, microbes went to town, eating ancient carbon that had been locked up in the ice.
Foolish microbes. They made the Earth too hot and cooked themselves.
Then again, the microbes may have more modest goals than us humans. We’ve found no fossils suggesting that the microbes tried to build spaceships.
For our endeavors, we’ve benefited from a few thousand years of extremely stable, mild climate.
We still have 8.5 hours left to build some spaceships, but a thirty second hot squall at 10:59 a.m. would doom the entire project.
So much time stretches out in front of us. We could have a great day. We, in continuation of the minute of humans who preceded us, and continued by the seconds or minutes or hours of humans who will be born next.
We shouldn’t let our myopic focus on present growth fuck up the entire day.
Honestly? My children are four and six. I’d be so disappointed if I took them for a hike and they guzzled all their water, devoured all their snacks, within the first minute after we left our house.
Recently, a dear friend sent me an article from Scientific American about the blanket octopus.
She and I had been discussing unusual animal mating, because that’s what you do, right? Global pandemic hits and you share freaky trivia with your friends.
Miniscule male anglerfish will merge with the body of a female if they find her, feeding off her blood. Deadbeat male clinginess at its worst.
Blanket octopuses also have extreme sexual dimorphism – a female’s tentacles can span seven feet wide, whereas the males are smaller than an inch.
But, wait, there’s more! In a 1963 article for Science magazine, marine biologist Everet Jones speculated that blanket octopuses might use jellyfish stingers as weapons.
While on a research cruise, Jones installed a night-light station to investigate the local fish.
“Among the frequent visitors to the submerged light were a number of immature female blanket octopuses. I dip-netted one of these from the water and lifted it by hand out of the net. I experienced sudden and severe pain and involuntarily threw the octopus back into the water.”
“To determine the mechanism responsible for this sensation, 10 or 12 small octopuses were captured and I purposely placed each one on the tender areas of my hands. The severe pain occurred each time, but careful observation indicated that I was not being bitten.
“The pain and resulting inflammation, which lasted several days, resembled the stings of the Portuguese man-of-war jellyfish, which was quite abundant in the area.”
tl;dr – “It really hurt! So I did it again.”
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My spouse teaches high school biology. An important part of her class is addressing misconceptions about what science is.
Every so often, newspapers will send a reporter to interview my father about his research. Each time, they ask him to put on a lab coat and pipette something:
I mean, look at that – clearly, SCIENCE is happening here.
But it’s important to realize that this isn’t always what science looks like. Most of the time, academic researchers aren’t wearing lab coats. And most of the time, science isn’t done in a laboratory.
Careful observation of the natural world. Repeated tests to discover, if I do this, what will happen next? There are important parts of science, and these were practiced by our ancestors for thousands of years, long before anyone had laboratories. Indigenous people around the world have known so much about their local varieties of medicinal plants, and that’s knowledge that can only be acquired through scientific practice.
A nine month old who keeps pushing blocks off the edge of the high chair tray to see, will this block fall down, too? That’s science!
And this octopus article, published in the world’s most prestigious research journal? The experiment was to scoop up octopuses by hand and see how much it hurt.
It hurt a lot.
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The article that I linked to earlier, the Scientific American blog post that my friend had sent me, includes a video clip at the bottom. Here’s a direct link to the video:
I should warn, you, though. The first section of the video shows a blanket octopus streaming gracefully through the ocean. She’s beautiful. But then the clip continues with footage of a huge school of fish.
Obviously, I was hoping that they’d show the octopus lurch forward, wielding those jellyfish stingers like electrified nun-chucks to incapacitate the fish. I mean, yes, I’m vegan. I don’t want the fish to die. But an octopus has to eat. And, if the octopus is going to practice wicked cool tool-using martial arts, then I obviously want to see it.
But I can’t. Our oceans are big, and deep, and dark. We’re still making new discoveries when we send cameras down there. So far, nobody has ever filmed a blanket octopus catching fish this way.
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Every time I learn something new about octopuses, I think about family reunions.
About twenty years ago, I attended a family reunion in upstate New York. My grandparents were celebrating their fiftieth wedding anniversary. Many people were there whom I’d never met before, and whom I haven’t seen since. But most of us shared ancestors, often four or five or even six generations back.
And we all shared ancestors at some point, even the people who’d married in. From the beginning of life on Earth until 150,000 years ago, you could draw a single lineage – _____ begat ______ who begat ______ – that leads up to every single human alive today. We have an ancestor in common who lived 150,000 years ago, and so every lineage that leads to her will be shared by us all.
There’s also an ancestor that all humans alive today share with all octopuses alive today. So we could host a family reunion for all of her descendants – we humans would be invited, and blanket octopuses would be, too.
I would love to meet a blanket octopus. They’re brilliant creatures. If we could find a way to communicate, I’m sure there’d be lots to talk about.
But there’s a problem. You see, not everyone invited to this family reunion would be a scintillating conversationalist.
That ancestor we share? Here’s a drawing of her from Jian Han et al.’s Naturearticle.
She was about the size of a grain of rice.
And, yes, some of her descendants are brilliant. Octopuses. Dolphins. Crows. Chimpanzees. Us.
But this family reunion would also include a bunch of worms, moles, snails, and bugs. A lot of bugs. Almost every animals would’ve been invited, excluding only jellyfish and sponges. Many of the guests would want to lay eggs in the potato salad.
So, sure, it’d be cool to get to meet up with the octopuses, our long-lost undersea cousins. But we might end up seated next to an earthworm instead.
I’m sure that worms are very nice. Charles Darwin was fascinated by the intelligence of earthworms. Still, it’s hard to have a conversation with somebody when you don’t have a lot of common interests.
I try to feed my children every night, but I never vomit blood into their mouths.
When I try to hang upside down – like from monkey bars at a playground – I have to clench my muscles, and pretty soon I get dizzy. I couldn’t spend a whole day like that.
And, yes, sometimes I shout. Too often during the pandemic, I’ve shouted at my kids. But when I shout, I’m trying to make them stop hitting each other – I’m not trying to figure out where they are.
It’s pretty clear that I’m not a bat.
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Photograph by Anne Brooke, USFWS
Because I haven’t had these experiences, philosopher Thomas Nagel would argue that I can’t know how it feels to be a bat.
In so far as I can imagine [flitting through the dark, catching moths in my mouth], it tells me only what it would be like for me to behave as a bat behaves.
But that is not the question. I want to know what it is like for a bat to be a bat.
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Perhaps I can’t know what it feels like for a bat to be a bat. And yet, I can empathize with a bat. I can imagine how it might feel to be trapped in a small room while a gamboling, wiry-limbed orc-thing tried to swat me with a broom.
It would be terrifying!
And that act of imagination – of empathy – is enough for me to want to protect bats’ habitats. To make space for them in our world. Sure, you could argue that bats are helpful for us – they’re pollinators, they eat pesky bugs – but empathy lets us care about the well-being of bats for their own sake.
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Literature exercises our minds: when we read, invent, and share stories, we build our capacity for empathy, becoming more generally aware of the world outside our own skulls.
Writing can be a radical act of love. Especially when we write from a perspective that differs from our own. The poet Ai said that “Whoever wants to speak in my poems is allowed to speak, regardless of sex, race, creed, or color.” Her poems often unfurl from the perspective of violent men, and yet she treats her protagonists with respect and kindness. Ai gives them more than they deserve: “I don’t know if I embrace them, but I love them.”
Ai
That capacity for love, for empathy, will let us save the world. Although many of us haven’t personally experienced a lifetime of racist microaggressions or conflict with systemic oppression, we all need to understand how rotten it would feel. We need to understand that the pervasive stress seeps into a person’s bones, causing all manner of health problems. We need understand the urgency of building a world where all children feel safe.
And if we don’t understand – yet – maybe we need to read more.
Experiments suggest that reading any engaging literary fiction boosts our ability to empathize with others. Practice makes better: get outside your head for a while, it’ll be easier to do it again next time.
Of course, we’ll still need to make an effort to learn what others are going through. Thomas Nagel was able to ruminate so extensively about what it would feel like to live as a bat because we’ve learned about echolocation, about their feeding habits, about their family lives. If we want to be effective anti-racists, we need to learn about Black experiences in addition to developing our empathy more generally.
As a bookish White person, it’s easy for me to empathize with the experiences of other bookish White people. In Search of Lost Time doesn’t tax my brain. Nor does White Noise. The characters in these books are a lot like me.
The cognitive distance between me and the protagonists of Americanah is bigger. Which is sad in and of itself – as high schoolers, these characters were playful, bookish, and trusting, no different from my friends or me. But then they were forced to endure hard times that I was sufficiently privileged to avoid. And so when I read about their lives, perched as I was atop my mountain of privilege, it was painful to watch Ifemelu and Obinze develop their self-protective emotional carapaces, armoring themselves against the injustice that ceaselessly buffets them.
Another reader might nod and think, I’ve been there. I had to exercise my imagination.
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In Being a Beast, Charles Foster describes his attempts to understand the lives of other animals. He spent time mimicking their behaviors – crawling naked across the dirt, eating worms, sleeping in an earthen burrow. He wanted a badger’s-eye view of the world.
Foster concluded that his project was a failure – other animals’ lives are just so different from ours.
And yet, as a direct consequence of his attempt at understanding, Foster changed his life. He began treating other animals with more kindness and respect. To me, this makes his project a success.
White people might never understand exactly how it feels to be Black in America. I’m sure I don’t. But we can all change the way we live. We can, for instance, resolve to spend more money on Black communities, and spend it on more services than just policing.
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Empathy is working when it forces us to act. After all, what we do matters more than what we purport to think.
It’s interesting to speculate what it would feel like to share another’s thoughts – in Robert Jackson Bennett’s Shorefall, the protagonists find a way to temporarily join minds. This overwhelming rush of empathy and love transforms them: “Every human being should feel obliged to try this once.”
In the real world, we might never know exactly how the world feels to someone else. But Nagel wants to prove, with words, that he has understood another’s experience.
One might try, for example, to develop concepts that could be used to explain to a person blind from birth what it was like to see. One would reach a blank wall eventually, but it should be possible to devise a method of expressing in objective terms much more than we can at present, and with much greater precision.
The loose intermodal analogies – for example, “Red is like the sound of a trumpet” – which crop up in discussions of this subject are of little use. That should be clear to anyone who has both heard a trumpet and seen red.
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We associate red with many of our strongest emotions: anger, violence, love.
And we could tell many different “just so” stories to explain why we have these associations.
Like:
Red is an angry color because people’s faces flush red when they’re mad. Red blood flows when we’re hurt, or when we hurt another.
Or:
Red represents love because a red glow spreads over our partners’ necks and chests and earlobes as we kiss and caress and fumble together.
Or:
Red is mysterious because a red hue fills the sky at dawn and dusk, the liminal hours when we are closest to the spirit world.
These are all emergent associations – they’re unrelated to the original evolutionary incentive that let us see red. Each contributes to how we see red now, but none explains the underlying why.
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We humans are blue-green-red trichromatic – we can distinguish thousands of colors, but our brains do this by comparing the relative intensities of just three.
And we use the phrase “color blind” to describe the people and other animals who can’t distinguish red from green. But all humans are color blind – there are colors we can’t see. To us, a warm body looks identical to a cold wax replica. But their colors are different, as any bullfrog could tell you.
Photograph by Tim Mosenfelder, Getty Images
Our eyes lack the receptors – cone cells with a particular fold of opsin – that could distinguish infrared light from other wavelengths. We mistakenly assume these two singers have the same color skin.
When we look at flowers, we often fail to see the beautiful patterns that decorate their petals. These decorations are obvious to any bee, but we’re oblivious. Again, we’re missing the type of cone cells that would let us see. To fully appreciate flowers, we’d need receptors that distinguish ultraviolet light from blue.
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Most humans can see the color red because we’re descended from fruit eaters. To our bellies, a red berry is very different from a green berry. And so, over many generations, our ancestors who could see the difference were able to gather more nutritious berries than their neighbors. Because they had genes that let them see red, they were better able to survive, have children, and keep their children fed.
The genes for seeing red spread.
Now, several hundred thousand years later, this wavelength of light blares at us like a trumpet. Even though the our ancestors learned to cook food with fire, and switched from fruit gathering to hunting, and then built big grocery stores where the bright flashes of color are just advertisements for a new type of high-fructose-corn-syrup-flavored cereal, red still blares at us.
Once upon a time, we really needed to see ripe fruit. The color red became striking to us, wherever we saw it. And so we invented new associations – rage, or love – even though these are totally unrelated to the evolutionary pressures that gave us our red vision.
Similarly, empathy wasn’t “supposed” to let us build a better world. Evolution doesn’t care about fairness.
And yet. Even though I might never know exactly how it feels when you see the color red, I can still care how you’re treated. Maybe that’s enough.
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Header image: a greater short-nosed fruit bat, photograph by Anton 17.
“Yeah, my grandfather had something like a thousand chickens, had them running all through the yard,” somebody said. “And there was this one chicken, he was a mean one. I was kind of afraid of it, strutting around like he owned the place. So my grandfather, he told me to kick it.”
“Well, I did, but that only made things worse. I didn’t make him scared, I just made that chicken hate me. So after that, anytime we went to visit my grandfather’s place, that chicken would be there, waiting for me.”
“My parents, my brothers and sisters, everybody would get out of the car, but the chicken wouldn’t bother them. He’d be sitting there, staring, just waiting for me. And when I finally got out I had to run, every time, sprinting to my grandfather’s front door before that chicken got me.”
“They live a long time, too! I had, like, five or six years of that! And still to this day, anytime my mom sees a video or a picture of somebody running from a chicken on Facebook, she’ll tag me in it. Like, ha ha ha, remember that?”
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“Maybe you didn’t kick him hard enough,” somebody suggested. “Cause we used to have chickens, and I had to go into the coop sometimes, and the roof of it was real low to the ground, so I had to crouch in there like this, and one chicken would always strut up to me like it was going to start something.”
“Well, it did that every time for a few months, till one day it got in my face and I just went BOOM, and I wrestled that little fucker to the ground. And that chicken never messed with me again.”
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Birds can recognize individual humans.
Biologist John Marzluff noticed that crows became wary of particular researchers after the crows had been captured and tagged. In an experiment where researchers captured a half dozen crows while wearing a caveman mask, they found that the whole flock learned to respond to that mask as a threat. Several years later, even crows who hadn’t seen the caveman’s initial misbehavior would shriek a warning when they saw that mask. They’d been trained by their flockmates.
The caveman mask is on the left. On the right: a control mask.
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Between their intelligence and acute eyesight, birds can serve as passable oncologists. Pigeons were trained with a set of slides from biopsies – a pigeon had to inspect each image and then choose a button for “cancer” or “not cancer”. If the pigeon chose correctly, the computer would dispense a pellet of food.
(Human medical students are often mistreated during their training, forced to work grueling hours with few breaks. The pigeon trainees were also mistreated – to ensure that they valued each food pellet, the pigeons were starved during the experiment. I’m 6 feet tall and about 150 pounds, but if I were participating in this study, I’d be kept at 127 pounds – eighty-five percent of my “free feeding” weight.)
You can buy 50 pounds of pigeon pellets for under $10. That’d give you enough rewards for a flock of half-starved pigeons to diagnose thousands of patients.
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We used to think that an entire class of vertebrates had gone extinct – the dinosaurs. But we now know that birds are dinosaurs.
Several species of dinosaurs/birds are gone – millions of years have passed since tyrannosaurs or velociraptors roamed the earth. But their lineage has continued.
When I was growing up, people often remarked that dinosaurs were clearly dim-witted creatures because they have such small cranial cavities. There was not much room for brains in their skulls!
When biologist Suzana Herculano-Houzel investigated the brains of various species, she found that the number of neurons in a brain typically correlates with cognitive capacity. More neurons makes for a smarter critter!
As it happens, birds’ brains are constructed better than our own. Crows and parrots pack neurons into a brain more densely than we do, like the difference between old IBM mainframes and modern telephones. Pigeon brains are better than ours at parallel computing, like the difference between a hypothetical quantum computer and your current laptop.
We can outsmart crows, parrots, and pigeons, but only because our raw neuron counts are so high that we’ve not been surpassed by their superior designs.
We don’t know when dinosaurs/birds evolved their high neuron densities – well-designed brains might be recent innovations, or they might be millions of years old. Ancient dinosaurs may have been far more intelligent than we thought.
Yes, they still went extinct, but you can’t blame them for succumbing to climate change. And it’s not like they caused the climate change that killed them.
Future archaeologists might judge humans to be more foolish than any stegosaurus.
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We humans have huge numbers of neurons in our cerebral cortex. We are blisteringly clever. We’ve made all variety of tools, languages, and complex social structures. Yes, crows also have tools, language, and complex social structures, but in each category, human achievements are even more complex.
A crow tool is typically a hooked piece of stick. We built telephones.
Well, humans collectively built telephones. I couldn’t sit down and build one from scratch. If I were to make a tool while out hiking, it’d probably be a hooked piece of stick.
Still, our best achievements are pretty incredible.
But we’ve also brought our species to the brink of extinction. Through overpopulation and excessive exploitation of the planet’s trapped resources, we’re making our world less habitable.
Tyrannosaurus ruled this planet for a few million years. Humans have been a dominant species for only a hundred thousand years – a few percent of T-Rex’s reign. With the current pace of climate change, scientists soberly discuss the possibility that we’ll reap apocalypse within a hundred more years.
Measured by reign, we might prove 20-fold less successful than those giant birds.
Our criminal justice system ensnares people from all walks of life. Occasionally we’ll hear about the arrest of a wealthy sociopath with a penchant for child abuse, like Jared Fogel or Jeffrey Epstein.
But, let’s face it. Justice in this country isn’t applied fairly. If you’re wealthy, your behavior has to be a lot more egregious for you to reap the same punishments as a poor person. If you look white, your behavior has to a lot more egregious for you to reap the same punishments as a black person.
There’s abundant statistical evidence to back up these claims. But the Supreme Court won’t allow any particular individual to petition for reduced punishment based on the statistical evidence. After all, prosecutors, judges, and juries ostensibly came to their decisions based on the unique details of each individual case. Just because people who resemble you are often treated unfairly doesn’t mean that you were treated unfairly, too.
Because we apply punishment so inequitably, our jails and prisons are full of people who’ve been treated poorly by the world. Compared to the average citizen, people in prison grew up with less money, received less education, experienced more trauma. And, no matter what people’s earlier lives were like, if they’re in prison, they’re not being treated well now.
So they have a lot of justifiable grievances against the dominant political, cultural, and religious beliefs of our country. Punished unfairly by their fellow Christians, people sour on Christianity. Inside walls where the demographics make it blatantly obvious that our laws are enforced in a malignantly racist way, racial tensions boil.
At Pages to Prisoners, an organization that sends free books to people inside, we get requests for stuff about Norse mythology, Odinism, and Asatru. Lots of folks ask for material to learn foreign languages – people want to feel like they’ve accomplished something during their time in prison – but I always feel skeptical when somebody wants help learning Icelandic.
Not that there’s anything wrong with Icelandic. And Norse mythology is cool! Unfortunately, a gaggle of violent white supremacists decided that Norse mythology should be the basis for their religion. Starting in the 1970s, a right-wing racist from Florida began sending “Odinist” publications into prisons.
During the thirteenth century, Christian scholars transcribed many of the old Norse myths so that they could better understand the literary allusions of old Icelandic poetry. But they didn’t record anything about ancient religious practice. We barely have any information about most ancient pagan beliefs. Anyone who wants to adopt a pre-Christian European religion now – whether it’s Wicca, Druidism, Odinism, or Celtic polytheism – is basically forced to make things up.
I have nothing against religious invention. All religions were made by human beings – there’s no a priori reason why a religion created long ago, by people who understood much less about the world than we do now, would be better than something you invent today. Sure, ancient religions have been tested by time, suggesting that they possess virtues that their practitioners found helpful over the years, but most ancient religions have their problems, too. Inaccurate cosmologies, scattered hateful passages in their texts, that sort of thing.
So I like the idea of neo-paganism. You want to find a clearing in the woods and
do some moonlit dancing? You’d rather
worship a feminine generative force than a norm-enforcing patriarchal deity? You want to exalt nature as a hearth to be
protected rather than a resource to be exploited? Go right ahead! All of that sounds pretty great to me.
Unfortunately,
neo-paganism as it’s currently practiced in prison tends to be pretty hateful.
That’s why I’ve been
working on a set of anti-racist pamphlets about Norse mythology. Currently, when people ask for The Poetic
Edda or whatever, we send a friendly letter saying that we don’t have it,
and also that we generally don’t stock that sort of thing because it runs afoul
of our anti-hate policy.
But the Norse myths are
certainly no more hateful than Biblical myths, and we send plenty of
those. The main difference is that
centuries of continued Christian practice have created a scaffolding of gentler
beliefs around the stories in the Bible.
The text of Psalm 137
states that “Happy shall he be, that taketh and dasheth thy little
ones against the stones.” But the
text is a tool, not the entirety of the religion. The practice of Christianity frowns upon
the murder of any human infant. Whether
you like the kid’s parents or not.
We’d be better off if Pages to Prisoners could send warm-hearted material about Norse mythology to people. Sure, you can interpret the Norse myths as endorsing a war-mongering death cult. You can interpret the Old Testament that way, too. But you can also interpret the Norse myths as environmentalist. Feminist. Supporting the pursuit of knowledge. Judging strangers based upon their merits, not their appearance.
Because contemporary
Odinism is so entangled with white supremacy, though, our pamphlet will have to
address skin color and genetic heritage directly. It’s a fraught topic. Lots of people in the U.S. don’t like any discussion
of evolution. Some people feel squigged
out when they learn that contemporary birds evolved from the same set of common
ancestors as the dinosaurs. And that’s far
less emotionally charged than a description of human evolution.
Plus, skin color still has huge implications for how people are treated in the United States. Consider, um, those prison demographics I cited above. And so discussions about the evolution of epidermal melanin concentrations are especially tense. Although the underlying biology is simple – some places have more sunlight than others! – because people think it matters, it does.
I’ve found that these conversations are actually a decent way to get people interested in the study of archeology and biology, though. After we’ve discussed this in jail, people have asked me to bring research papers and textbooks so that they could learn more.
Whenever two groups of an organism stop mating with each other, they’ll slowly drift apart. This rift might occur because the groups became physically separated from each other. Maybe one group migrated to an island. In contemporary times, maybe the groups were separated when humans built a new highway bisecting a habitat. Maybe two sets of similar-looking insects mate apart because they’re eating fruits that ripen at different times.
Or the groups might stop mating with each other because a chance mutation caused members of one group to want their sexual partners to smell a certain way. Various species of stickleback are able to interbreed – they identify other members of their kind based on smell. But water pollution has overwhelmed the fishes’s senses, leading the fish to mate indiscriminately.
If humans hadn’t
polluted their waters, though, these sticklebacks would have drifted farther
and farther apart until it became impossible for them to interbreed. No matter how many sense-suppressing
chemicals we dumped.
We don’t know what caused the initial rift between our ancestors and the ancestors of contemporary chimpanzees. About 4 million years ago, though, these groups stopped having children together. By 2 millions years ago (at least 100,000 generations later), these groups looked quite different from each other. Although it’s possible that these organisms could have still mated with each other and raised viable progeny, they rarely did.
One group of these
creatures, which included our ancestors, had a tucked pelvis and mostly upright
posture. This allowed for a good vantage
while scavenging and, eventually, hunting.
The other group, which includes chimpanzees’ ancestors, mostly moved on
all fours. This body plan results in
fewer mothers dying during childbirth.
As ever, there are trade-offs to be made.
Up until about 2 million
years ago, all our ancestors lived in Africa.
But then they began to migrate.
Over the next million years, they explored much of the globe. By about 500,000 years ago, half a dozen
different types of humans lived in Africa, Europe, and Asia. The difference between one population to the
next was not like the racial differences among contemporary humans, but more
like the difference between lions and tigers, or between polar bears and brown
bears. Scientists describe them as
distinct species. Although they were
similar enough that they could have sex and raise children together, they
rarely did – they lived in distinct parts of the world and had begun to evolve
adaptations to their specific environments.
Evolution isn’t easy. Nor is it quick. Just because a certain trait would be
advantageous doesn’t mean that creatures will acquire it. In the desert, it would help to have
adaptations for water retention like camels, or long ears like jackrabbits to
cool the blood. But a trait can only
spread after a random mutation creates it.
And, even if a trait is very helpful, if only one individual is born
with the adaptation, there’s no guarantee that it will have enough children for
the benefit to spread through the population.
Once a beneficial trait has a good toe-hold – present in perhaps 1% to 10% of the population – then we can expect it to flourish. But below that amount, even great adaptations might die off due to bad luck. That’s why it takes so many generations – tens of thousands, or hundreds of thousands – before you see organisms become drastically better suited for the environment. Even when scientists do directed evolution experiments in the lab, it takes about this many generations for a population of bacteria to evolve ways to consume a new food source, for instance.
By 500,000 years ago, the various species of humans were recognizably different. Denisovans lived in the mountains, and their hemoglobin genes allowed them to avoid altitude sickness. Their blood was less likely to clot and cause strokes, and they could extract more oxygen from the thin air. These are incredibly beneficial traits. Even though the Denisovans went extinct about 40,000 years ago, about 40% of people currently living in Tibet have copies of the Denisovan hemoglobin gene.
Our ancestors migrated east to the Denisovans’ homeland just before the Denisovans went extinct. To be perfectly honest, we probably killed them. But before or during this genocide, a few of our ancestors must have had sex with the locals. And then the bi-racial children of these Homo sapiens / Denisovan couplings must have been significantly better off for the gene to spread so widely.
The Neanderthal lived at
high latitude. Over many generations,
their average skin color became paler.
In part, this was probably due to the lack of selective pressure. Think about a dodo – there was no advantage
for these birds to lose their fear of humans.
But, because the dodos were living on an island that no humans traveled
to, there was also no harm in the birds becoming fearless.
Dodos lost a beneficial
trait – fear – because their fear wasn’t actively needed. It’s kind of like the airbags in an old
car. If your car’s engine goes bad,
you’ll notice right away. Turn the key,
hear it sputter. You use the engine
every time you drive. But your airbags
could get worse without you noticing … and then, in the moment when they’re
needed, they won’t deploy.
Humans living near the equator need epidermal melanin. If you don’t have enough melanin, you’ll get sunburns, which exacerbate the risk of infection and dehydration; you’ll suffer radiation-induced DNA damage, which leads to skin cancer; and you’ll lose folate, which means that pregnant women will have more birth defects.
The most recent ancestors
that humans and chimpanzees shared in common had pale skin. Contemporary chimpanzees are still pale. They can afford to be – their fur protects
them from the sun. But our ancestors
lost their fur, probably so that they didn’t overheat while running, and this
led to the evolution of dark skin.
High concentrations of
epidermal melanin distinguished humans from the other apes.
As humans migrated to
higher latitudes, though, they gradually lost this indicator of their
humanity. Because the sunlight was less
intense, there was less selective pressure.
Humans could lose their epidermal melanin in the same way that dodos
lost their fear – not because it was helpful to go without it, but because the
trait went untested in their day to day lives.
They had no way to “realize” how important it was.
Your airbags aren’t
helpful until you crash. And then
they’ll either deploy and save you, or they won’t.
Now, it’s possible that the Neanderthal also experienced some positive selective pressure on their skin color as they migrated north. Over thousands of generations, the Neanderthals may have benefited from paler skin because it increased their production of vitamin D. We don’t know for certain that the Neanderthal felt any evolutionary pressure to have more vitamin D – after all, contemporary Inuit people live at very high latitudes but still have a lot of epidermal melanin – but it’s true that vitamin D deficiency is a big risk among people with crummy diets.
In the past, hunter / gatherers typically ate much healthier, more varied diets than farmers. When humans began to farm, they would mostly eat the one type of plant that they cultivated, rather than the wide mix of plants that could be found growing wild. And when Homo sapiens farmers migrated to northern Europe, their diets were so poor that they even developed loss-of-function mutations in a cholesterol synthesis gene, probably so that they’d have higher concentrations of vitamin D precursors. Among these people, pale skin was probably a big advantage. They’d be ready for the cloudless days when their homeland’s feeble sunlight was enough to make some vitamin D.
Pieter Bruegel the Elder’s The Harvesters.
Around 40,000 years ago,
our planet’s most recent ice age ended.
The world began to warm, and glaciers retreated from Europe. By then, a group of humans living in Africa
were recognizably Homo sapiens.
These were our ancestors. Every
human alive today – no matter what you look like or where your family is from –
is descended from this group of people from Africa. They lived in tribes of twenty to a hundred
people, had darkly pigmented skin, made art, and spoke complex languages.
As the world warmed, some
of these Homo sapiens began to migrate.
These journeys occurred over many generations. Some tribes stayed in Africa; some tribes
ventured north into Europe; others moved east toward Asia. As they traveled, they encountered the humans
who already lived in those places. As
I’ve mentioned, the newcomers occasionally had sex and raised children with the
natives. They probably also killed a lot
of them. Unfortunately, we Homo
sapiens don’t have the best reputation for treating strangers well.
Interbreeding happened
rarely enough that most people living today have about 99% Homo sapiens DNA. Some people, especially if their families are
from Africa, have essentially 100% Homo sapiens DNA. At other extreme, even people whose families
are from Europe have 96% or more Homo sapiens DNA.
Among people living in
Tibet, the Denisovan hemoglobin gene is common, but most other Denisovan genes
are gone.
Like the Neanderthal
before them, the Homo sapiens who ventured north into Europe began to
lose their epidermal melanin. People who
hunted and fished probably became paler simply because there was less risk of
sun damage. Remember, this didn’t happen
all at once. Average skin color would
change only over the course of hundreds or even thousands of generations, not
during the course of a single journeying Homo sapiens’s lifetime.
Our ancestors spent almost
all their time outdoors, which is why even dark-skinned people could probably
synthesize plenty of vitamin D. Among
contemporary humans, vitamin D deficiency is such a big problem because we
spend too much time inside. As I type
this, I’m sitting at a table in the YMCA snack room, lit up by flickering
fluorescent bulbs. This low-quality
light won’t help me make vitamin D.
Instead, I take a daily
supplement. But that doesn’t come near
matching the health and psychological benefits of time outdoors.
Perhaps it’s worth mentioning that people in jail – places not known for providing a rich, high-quality, varied diet – typically get to go outside no more often than once a week. At our local jail, their hour of “outdoor rec” occurs in a little courtyard at the top of the jail, a cement space covered with a chain-linked fence. Outdoor rec often happened at night – a friend who was recently released told me that “This was still nice. You could see some stars. And there’s that restaurant, Little Zagrib, down the street? Sometimes we’d smell foods from their kitchen.”
Treating people that way
is unlikely to help them get better.
But back to our migrants! Descendants of these pale-skinned Homo sapiens continued to explore new territories. Some reached North America about 12,000 years ago, and some of their descendants continued farther, all the way to South America.
As people traveled –
journeys that lasted many generations – they continued to evolve. Indeed, skin color was a trait that came
repeatedly under selective pressure. As
people migrated south into the Americas, they were living progressively closer
and closer to the equator. Compared to
their grandparents, they were bombarded by more intense sunlight. They needed more epidermal melanin.
This is a process that
takes a long time. A family might have
six kids; maybe the two palest kids get sunburned, which makes it more likely
that they’ll develop skin infections and die before they have children of their
own. If this happens again and again,
among many different families, then eventually the whole population will wind
up with slightly darker skin.
A prediction for the distribution of human skin colors based on the intensity of ultraviolet light present at each latitude. Figure from Nina Jablonski & George Chaplin, “The Evolution of Human Skin Color,” in Journal of Human Evolution, 2000.
This figure depicts the (limited) data we have on the distribution of human skin colors before the modern era’s horrific set of forced migrations. In this image, white-colored regions indicate an absence of data, not low concentrations of epidermal melanin among a region’s prehistoric population. Figure from Nina Jablonski & George Chaplin, “The Evolution of Human Skin Color,” in Journal of Human Evolution, 2000.
Because human skin color
has changed during each of the many prehistoric migrations, it isn’t correlated
with other traits. As we entered the
modern era, people’s skin color was lighter or darker based on how close to the
equator their recent ancestors lived.
But human populations migrated so often that there were many different
groups, each with unique cultural and genetic heritages, living at every
latitude. Because skin color is so
closely linked to latitude, this means many different groups shared similar
concentrations of epidermal melanin. And
there’s no evolutionary pressure linking a trait that protects skin to brain
size or intelligence.
As it happens, there are
major events known to have caused a decrease in human brain size (and probably
intelligence). After all, human brains
are costly. Even though there’s a
benefit to being clever, there’s also been constant evolutionary pressure against
large brains.
Large brains kill
mothers. Because humans walk upright,
childbirth is riskier for human mothers than for other primates. Our posture constrains the width of our hips
– both male and female – but a baby’s whole head has to pass through that
narrow passageway.
Having children is so
risky that we evolved to give birth about 3 months prematurely. Human gestation takes about a year, but most
mothers give birth after only 9 months.
This allows a baby’s head to continue to grow outside the mother’s body,
but human babies are totally helpless at birth.
We have to be very devoted parents to keep them alive.
Also, our brains require a
lot of fuel. Human evolution occurred
over such a long, long time that our ancestors lived through many droughts and
calamities. During the hard years, our
ancestors would struggle to get enough to eat, and a large brain makes that
struggle harder.
A person with a smaller
brain requires fewer calories, making that person less likely to starve in lean
times. And, again, it’s worth
remembering that evolution happens over so many generations, among so many
families, that even small changes can add up.
If mothers who have small-headed children can survive a dozen
pregnancies, but mothers with large-headed children die after only a few, then
the trend will be to have people with smaller brains. Intelligence has to be extremely
beneficial to overcome this sort of evolutionary pressure.
Similarly, if people with
small brains are more likely to survive and raise children during droughts,
then, after hundreds of generations of people who have survived dozens of
extended droughts, you’d expect to see more people with small brains.
Many of us have the bad
habit of reflexively thinking about evolution as the gradual development of
more and more complexity. But that’s not
what it is. Evolution is the process by
which things that are better suited for their environment become more
abundant. If the environment is a hard
place to live in, then evolution tends to push for more and more simplicity. When it’s hard to get enough calories, why
waste calories on anything that you don’t really need?
Starfish are descended
from organisms that had brains. But
starfish are brainless. The ancestral
starfish that weren’t wasting energy thinking were more likely to survive.
Which should make you feel
pretty good about your own brain, actually.
Your ability to think is so fabulous that your ancestors evolved larger
and larger brains … even though these brains were sometimes causing us to
starve to death, or kill our mothers.
That’s a valuable thing
you’ve got inside your skull. It cost
our ancestors so much for you to be able to have it.
But, right. Because the cost was so high, human brains did shrink sometimes. Like when we first domesticated dogs. Our ancestors began living with dogs about 30,000 years ago. Dogs were willing to do some thinking for us – they’d sniff out prey and listen for predators at night. Based on the behavior of my family’s dogs, I bet that they licked the faces of screaming children. Maybe that doesn’t seem essential for survival, but I certainly appreciate every time our dogs calm the kids down.
Because we could slough
off a few mental tasks – I don’t need to be so observant if the dog will
help me hunt – our brains could shrink, making childbirth less deadly and
reducing the caloric cost of maintaining our minds each day.
When humans switched from hunting and gathering to agriculture, our brains shrunk further. A hunter / gatherer has to know so much about every plant and animal living nearby; the work asks more of a person’s brain than farming. This evolutionary trend was exacerbated by the fact that people’s diets became way worse when they began to farm. Instead of getting nutrition from a wide variety of different plants and animals, a farmer might eat meals consisting mostly of a single type of grain.
There’s nothing we can do now about these evolutionary trends. Dogs and farming swayed our ancestors’ evolution toward smaller brains, but it’s not as though you can get those neurons back by deciding to take up hunting, or never living with a pet.
But, honestly, our brains are so plastic that our genetic heritage matters less than how we choose to spend our time. By nature, neither gorillas nor parrots will speak human language. But individuals from both these species have been able to learn to communicate with us after we taught them.
Nobody is born with an
innate understanding of mythology, religion, science, or mathematics. None of that can be encoded in your
genes. If you want to understand this
stuff, you’ll have to make an effort to learn it.
Neuron count only suggests
a brain’s potential. You could do
incredible things with a low number – consider, by ways of analogy, the feats
that 1960s NASA accomplished using computers much smaller than a contemporary
telephone. And, conversely, sensory
deprivation will make it much harder to get things done, no matter what your
innate potential.
That’s why I volunteer with Pages to Prisoners. Our brains are capable of wonders. At any age, we can learn and grow. And yet, we lock people into prisons that seem designed to make them worse.
I love
this poem. There’s a undercurrent of
darkness as the bird constructs his pleasure dome. “Here, the iron smell of
blood.” But he is undeterred. “And there, the bowerbird. Watch as he manicures his lawn.”
This
bowerbird has themed his edifice around sparkling bits of blue. Bower birds incorporate all manner of found
objects: berries, beetles (which must be repeatedly returned to their places as
they attempt to crawl away), plastic scraps.
A bowerbird has a clear vision, a dream of which colors will go where,
and scours the forest to find the treasures he needs.
Will high-contrast white in front of the brown bower bedazzle guests? Our artist can only hope. Image by davidfntau on Flickr.
Female
bowerbirds raise children alone, so she doesn’t need a helpful partner.. Instead, she’ll choose someone who can show
her a good time. And her pleasure will
be enhanced by a beautiful dome, a splendid arch beneath which several seconds
of intercourse can transpire.
A mother-to-be typically visits several bowers before choosing her favorite. During each inspection, the male will hop and flutter during her evaluation … and then slump, dejected, if she flies away.
Kelly
closes her poem with the experience of a crestfallen artist: “And then, /
how the female finds him, / lacking.
All that blue for nothing.”
I
especially love the wry irony of that final sentence. We create art hoping to be fawned over; it’d
feel nice to know that readers enjoyed a poem so much that they responded with
a flush of desire for the author.
But this
is rare. No piece of writing will appeal
to all readers; an author is lucky if it appeals to any. The same holds true for painting, music, and
bowers. A bowerbird hopes that his
magnificent edifice will soon be the site of his acrobatic, if brief, bouts of
copulation. But his life will miserable
if he can’t also take pleasure in the sheer act of creation.
Female
tropical birds are free to select whichever male they want. Their flirtations are unlikely to be turned
down. And because each intimate
encounter is vanishingly brief, a single male might service every female in an
area. The other males, having assembled
less glorious bowers, will die without ever experiencing erotic delights.
And so a
bowerbird needs to enjoy his own arch.
To endure, to thole, even if no one wants to fool around with him. Even if no one looks. He needs to feel pleasure as he assembles
those beautiful hues. Every visiting
female might quickly fly away, but all that blue will have served a purpose.
I love
the poem “Bower,” but I also hope that Kelly enjoyed writing her poem enough
that my opinion doesn’t matter.
After
reading “Bower,” our class got sidetracked into a wide-ranging conversation about
birds. At first, we did talk about
bowerbirds. Most of the guys had no idea
that birds like that existed – that an animal might make art – but one
guy had seen a television show about them years ago, and the program made such
a deep impression on him that he still remembered much of it. “They really do,” he said. “I’ve seen it. And they showed the people nearby, somebody
who was eating breakfast cereal with like a plastic spoon, and this bird flew
right over and took it. Later they found
bits of it all broken up, in this weird ring around the bird’s nest.”
And then
this man started talking about crows.
He
gesticulated profusely as he talked, which was rather distracting. One of his hands had about 1.3 fingers; his
ring finger was missing entirely, and the others, including his thumb, ended
after the first knuckle. I wouldn’t have
felt so puzzled – stuff happens, after all – except that one of his stories
involved chasing somebody with a steak knife, and this was the hand he
brandished.
Many of the people in jail have suffered severe physical injuries. When we were discussing personality manipulation and mind control, someone told me that he’d been hit by a truck and that everything in his life had felt flat and emotionless ever since. He showed me the thick scar at the top of his head: “When it happened, I guess I was out for almost a week, and it took another month before I really remembered my name. Even then, for that first year I felt like I was back in eighth grade again.” He was twenty-something when it happened.
Another
time, I asked a man if he wanted to read the next poem and he said he couldn’t,
that he was disabled, then thumped his leg onto the table. He had a rounded stump where most people’s
foot would be. I didn’t quite see the
connection between his injury and the poem, and it’s not as though we ever
force people to read. We have a lot of
guys with dyslexia, and I go in with the goal of making their Fridays a little
more pleasant; no reason for somebody to suffer unnecessarily.
“I was
working in a saw mill,” he said. “Planer
caught me and, zzooomp. Didn’t even feel
anything, at first.”
He got a
legal settlement – a few guys muttered that they’d trade a foot for that kind
of money – but his pain script led to more opiates and eventually the money was
gone and he was in jail and the only help he was getting was from a PD.
But,
right, back to the man gesticulating wildly as he talked about birds. “Real smart animals,” he said. “Especially crows.”
The guy
went on: “See, I was living in a tent, and cops kept coming by, harassing
me. Cause there’d always be all this trash
on the ground. They’d say, ‘look, we
know that you’re sleeping here, but you can’t just leave all this shit
everywhere.’ And they’d make me clean it
up. I’d do it, but then a day or two
later, there’d be trash scattered everywhere again. I thought it must be some homeless guys or
something that was doing it.”
“But it
turned out these crows – they knew I was drinking, that I’d never be up before
about noon – and they were raiding the dumpster out behind McDonalds. I only found out because I actually woke up
one morning to piss. And I looked up and
these crows in the tree above me, they carried tied-off garbage bags way up
into that tree and were tearing them apart, looking for things to eat. And that’s how all that trash was getting
everywhere. I’d thought it was homeless
guys, and it was crows!”
Male
bowerbirds can afford to be such terrible parents because they live in tropical
forests where there’s an abundance of food to eat. Crows, though, need ingenuity to
survive. Sometimes they pick apart the
leavings of hairless apes below.
Because
crows raise their young in much harsher environs than bowerbirds, males
contribute more than just DNA. While a
mother roosts, the father will gather food.
And so he’ll try to impress a potential mate, beforehand, with his
gathering prowess. He won’t build,
paint, or compose poetry, but he’ll scour the land below for tasty treats and
shiny things, then leave these gifts at his beloved’s feet.
As with bowerbirds, some crows are helpful without reaping the benefits of a dalliance. When a female crow begins to build a nest, five other crows might bring sticks and twigs. These five won’t all be rewarded with the chance to sire her young.
With
luck, the crows enjoy the sheer act of helping.
Neither
birds nor humans will be lauded for everything we do. If we measure success based solely upon the
rewards we reap, many of our lives will feel bleak. In a world full of pyramids – bowerbird
mating, corporate finance, the attention economy of social media – not everyone
can be at the top.
No
matter the outcome, we can all feel fulfilled if we focus on the process
of what we’re doing.
Admittedly,
it’s hard to find the zen in a lot of the shitty jobs out there in the
world. But I did enjoy typing this
essay. And I will try to enjoy
the irritating parts of parenting today.
Someday, my children will learn to ask for cereal politely.
In the United States, people are having sex less often. And between alcohol, marijuana, recreational painkillers – not to mention anti-depressants and anti-anxiety medication – we take a lot of drugs.
Many of us work long hours at jobs we dislike so that we can afford to buy things that promise to fill some of the emptiness inside. The most lucrative businesses are advertising companies … one of which, Facebook, is designed to make you feel worse so that you’ll be more susceptible to its ads.
It might seem as though we
don’t know how to make people happier.
But, actually, we do.
Now, I know that I’ve written previously with bad medical advice, such as the suggestion that intentionally infecting yourself with the brain parasite Toxoplasma gondii could make you happier. This parasite boosts dopamine levels in your brain (dopamine is a neurotransmitter that conveys feelings of pleasure and mirth) and makes you feel bolder (in controlled laboratory experiments, infected mice show less stress when making risky decisions, and observational data suggests the same to be true for infected humans). You also might become more attractive (infected rodents have more sex, and portrait photographs of infected human men are perceived as more dominant and masculine).
There are drawbacks to Toxoplasma infection, of course. Infected rodents are more likely to be killed by cats. Infected humans may become slower as well, both physically and intellectually. Toxoplasma forms cysts in your brain. It might increase the chance of developing schizophrenia. It can kill you if you’re immunocompromised. And the surest way to contract toxoplasmosis, if incidental exposure hasn’t already done it for you, is by eating cat excrement.
My advice today is
different. No feces required!
And I’m not suggesting
anything illegal. I mentioned, above,
that people in the United States take a lot of drugs. Several of these boost dopamine levels in
your brain. Cocaine, for instance, is a
“dopamine re-uptake inhibitor,” ensuring that any momentary sensation of pleasure
will linger, allowing you to feel happy longer.
But cocaine has a nasty
side effect of leading to incarceration, especially if the local law
enforcement officers decide that your epidermal melanin concentration is too
high. And jail is not a happy
place.
Instead, you could make yourself happier with a bit of at-home trepanation, followed by the insertion of an electrode into the nucleus accumbens of your brain. Now, I know that sounds risky, what with the nucleus accumbens being way down near the base of your brain. But your brain is rather squishy – although you’ll sheer some cells as you cram a length of conductive wire into your cranium, the hope is that many neurons will be pushed out of the way.
The nucleus accumbens tends to show high activity during pleasure. For instance, cocaine stimulates activity in this part of your brain. So does money — tell research subjects that they’ve won a prize and you’ll see this region light up. If rats are implanted with an electrode that lets them jolt their own nucleus accumbens by pushing a lever, they’ll do it over and over. Pressing that lever makes them happier than eating, or drinking water, or having sex. They’ll blissfully self-stimulate until they collapse. From James Olds’s Science paper, “Self-Stimulation of the Brain”:
If animals with electrodes
in the hypothalamuswere run for 24 hours or 48 hours
consecutively, they continued to respond as long as physiological endurance
permitted.
Setup for Olds’s experiment.
Perhaps I should have
warned you – amateur brain modification would carry some risks. Even if you have the tools needed to drill
into your own skull without contracting a horrible infection, you don’t want to
boost your mood just to die of dehydration.
After all, happiness might have some purpose. There might be reasons why certain activities – like eating, drinking water, having sex … to say nothing of strolling outdoors, or volunteering to help others – make us feel happy. After discussing several case studies in their research article “How Happy Is Too Happy,” Matthis Synofzik, Thomas Schlaepfer, and Joseph Fins write that using deep brain stimulation for the “induction of chronic euphoria could also impair the person’s cognitive capacity to respond to reasons about which volitions and preferences are in his or her best interests.”
When an activity makes us
feel happy, we’re likely to do it again.
That’s how people manage to dedicate their lives to service. Or get addicted to drugs.
And it’s how brain
stimulation could be used for mind control.
If you show me a syringe,
I’ll feel nervous. I don’t particularly
like needles. But if you display that
same syringe to an intravenous drug user, you’ll trigger some of the rush of
actually shooting up. The men in my
poetry classes have said that they feel all tingly if they even see the word
“needle” written in a poem.
For months or years, needles
presaged a sudden flush of pleasure.
That linkage was enough for their brains to develop a fondness for the
needles themselves.
If you wanted to develop a taste for an unpalatable food, you could do the same thing. Like bittermelon – I enjoy bittermelons, which have a flavor that’s totally different from anything else I’ve ever eaten, but lots of people loathe them.
Still, if you used deep
brain stimulation to trigger pleasure every time a person ate bittermelon, that
person would soon enjoy it.
Bittermelon. Image by [cipher] in Tokyo, Japan on Wikimedia.
Or you could make someone
fall in love.
Far more effective than
any witch’s potion, that. Each time your
quarry encounters the future beloved, crank up the voltage. The beloved’s presence will soon be
associated with a sense of comfort and pleasure. And that sensation – stretched out for long
enough that the pair can build a set of shared memories – is much of what love
is.
Of course, it probably
sounds like I’m joking. You wouldn’t really
send jolts of electricity into the core of somebody’s brain so that he’d fall
in love with somebody new … right?
Fifty years passed between
the discovery of pleasure-inducing deep brain stimulation and its current use
as a treatment for depression … precisely because one of the pioneering
researchers decided that it was reasonable to use the electrodes as a
love potion.
In 1972, Charles Moan and Robert Heath published a scientific paper titled “Septal stimulation for the initiation of heterosexual behavior in a homosexual male.” Their study subject was a 24-year-old man who had been discharged from the military for homosexuality. Moan and Heath postulated that the right regimen of electrode stimulation – jolted while watching pornography, or while straddled by a female prostitute whom Moan and Heath hired to visit their lab – might lead this young man to desire physical intimacy with women.
Moan and Heath’s paper is
surprisingly salacious:
After about 20 min of such
interaction she begun [sic] to mount him, and though he
was somewhat reticent he did achieve penetration. Active intercourse followed during which she
had an orgasm that he was apparently able to sense. He became very excited at this and suggested
that they turn over in order that he might assume the initiative. In this position he often paused to delay
orgasm and to increase the duration of the pleasurable experience. Then, despite the milieu [inside a lab,
romping under the appraising eyes of multiple fully-clothed scientists] and
the encumbrance of the electrode wires, he successfully ejaculated. Subsequently, he expressed how much he had
enjoyed her and how he hoped that he would have sex with her again in the near
future.
The science writer Lone Frank recently published The Pleasure Shock, a meticulously researched book in which she concludes that Heath was unfairly maligned because most people in the 1970s were reticent to believe that consciousness arose from the interaction of perfectly ordinary matter inside our skulls. Changing a person’s mood with electricity sounds creepy, especially if you think that a mind is an ethereal, inviolable thing.
But it isn’t.
The mind, that is. The mind isn’t an ethereal, inviolable thing.
Zapping new thoughts into somebody’s brain, though, is definitely still understood (by me, at least) to be creepy.
Discussing the contemporary resurgence of electrical brain modification, Frank writes that:
In 2013, economist Ernst Fehr
of Zurich University experimented with transcranial direct current stimulation,
which sends a weak current through the cranium and is able to influence
activity in areas of the brain that lie closest to the skull.
Fehr had sixty-three
research subjects available. They played
a money game in which they each were given a sum and had to take a position on
how much they wanted to give an anonymous partner. In the first round, there were no sanctions
from the partner, but in the second series of experiments, the person in
question could protest and punish the subject.
There were two opposing
forces at play. A cultural norm for
sharing fairly – that is, equally – and a selfish interest in getting as much
as possible for oneself. Fehr and his people
found that the tug of war could be influenced by the right lateral prefrontal
cortex. When the stimulation increased
the brain activity, the subjects followed the fairness norm to a higher degree,
while they were more inclined to act selfishly when the activity was
diminished.
Perhaps the most
thought-provoking thing was that the research subjects did not themselves feel
any difference. When they were asked
about it, they said their idea of fairness had not changed, while the
selfishness of their behavior had changed.
Apparently, you can fiddle
with subtle moral parameters in a person without the person who is manipulated
being any the wiser.
The human brain evolved to create elaborate narratives that rationalize our own actions. As far as our consciousness is concerned, there’s no difference between telling a just so story about a decision we made un-aided, versus explaining a “choice” that we were guided toward by external current.
Frank believes that Heath
was a brilliant doctor who sincerely wanted to help patients.
When bioethicist Carl Elliott reviewed The Pleasure Shock for the New York Review of Books, however, he pointed out that even – perhaps especially – brilliant doctors who sincerely want to help patients can stumble into rampantly unethical behavior.
The problem isn’t just that Heath pulsed electricity into the brain of a homosexual man so that he could ejaculate while fooling around with a woman. Many of Heath’s patients – who, it’s worth acknowledging, had previously been confined to nightmarish asylums – developed infections from their electrode implantations and died. Also, Heath knowingly promoted fraudulent research findings because he’d staked his reputation on a particular theory and was loathe to admit that he’d been wrong (not that Heath has been the only professor to perpetuate falsehoods this way).
Elliott concludes that:
Heath was a physician in
love with his ideas.
Psychiatry has seen many
men like this. Heath’s contemporaries
include Ewen Cameron, the CIA-funded psychiatrist behind the infamous “psychic
driving” studies at McGill University, in which patients were drugged into
comas and subjected to repetitive messages or sounds for long periods, and
Walter Freeman, the inventor of the icepick lobotomy and its most fervent
evangelist.
These men may well have
started with the best of intentions. But
in medical research, good intentions can lead to the embalming table. All it takes is a powerful researcher with a
surplus of self-confidence, a supportive institution, and a ready supply of
vulnerable subjects.
Heath had them all.
It’s true that using an
electrode to stimulate the nucleus accumbens inside your brain can probably
make you feel happier. By way of
contrast, reading essays like this one make most people feel less happy.
Sometimes it’s good to
feel bad, though.
As Elliott reminds us, a
lot of vulnerable people were abused in this research. A lot of vulnerable people are still
treated with cavalier disregard, especially when folks with psychiatric issues
are snared by our country’s criminal justice system. And the torments that we dole upon non-human
animals are even worse.
[University of Chicago
researcher Inbal Ben-Ami Bartal] placed one rat in an enclosure, where it
encountered a small transparent container, a bit like a jelly jar. Squeezed inside it was another rat, locked
up, wriggling in distress.
Not only did the free rat learn how to open a little door to liberate the other, but she was remarkably eager to do so. Never trained on it, she did so spontaneously.
Then Bartal challenged her
motivation by giving her a choice between two containers, one with chocolate
chips – a favorite food that they could easily smell – and another with a
trapped companion. The free rat often
rescued her companion first, suggesting that reducing her distress counted more
than delicious food.
Is it possible that these
rats liberated their companions for companionship? While one rat is locked up, the other has no
chance to play, mate, or groom. Do they
just want to make contact? While the
original study failed to address this question, a different study created a
situation where rats could rescue each other without any chance of further
interaction. That they still did so
confirmed that the driving force is not a desire to be social.
Bartal believes it is
emotional contagion: rats become distressed when noticing the other’s distress,
which spurs them into action.
Conversely, when Bartal gave
her rats an anxiety-reducing drug, turning them into happy hippies, they still
knew how to open the little door to reach the chocolate chips, but in their
tranquil state, they had no interest in the trapped rat. They couldn’t care less, showing the sort of
emotional blunting of people on Prozac or pain-killers.
The rats became
insensitive to the other’s agony and ceased helping.
You could feel
happier. We know enough to be able to
reach into your mind and change it.
A miniscule flow of electrons is enough to trigger bliss.
But should we do it? Or use our unhappiness as fuel to change the
world instead?
Frank Brown Cloud 
