June 26, 2012
This image has been posted with express written permission. This cartoon was originally published at Town Hall.
June 26, 2012
“I am often asked whether I agree with the new group selectionists, and the questioners are always surprised when I say I do not. After all, group selection sounds like a reasonable extension of evolutionary theory and a plausible explanation of the social nature of humans. Also, the group selectionists tend to declare victory, and write as if their theory has already superseded a narrow, reductionist dogma that selection acts only at the level of genes. In this essay, I’ll explain why I think that this reasonableness is an illusion. The more carefully you think about group selection, the less sense it makes, and the more poorly it fits the facts of human psychology and history.”
Human beings live in groups, are affected by the fortunes of their groups, and sometimes make sacrifices that benefit their groups. Does this mean that the human brain has been shaped by natural selection to promote the welfare of the group in competition with other groups, even when it damages the welfare of the person and his or her kin? If so, does the theory of natural selection have to be revamped to designate “groups” as units of selection, analogous to the role played in the theory by genes?
Several scientists whom I greatly respect have said so in prominent places. And they have gone on to use the theory of group selection to make eye-opening claims about the human condition.[i] They have claimed that human morailty, particularly our willingness to engage in acts of altruism, can be explained as an adaptation to group-against-group competition. As E. O. Wilson explains, “In a group, selfish individuals beat altruistic individuals. But, groups of altruistic individuals beat groups of selfish individuals.” They have proposed that group selection can explain the mystery of religion, because a shared belief in supernatural beings can foster group cohesion. They suggest that evolution has equipped humans to solve tragedies of the commons (also known as collective action dilemmas and public goods games), in which actions that benefit the individual may harm the community; familiar examples include overfishing, highway congestion, tax evasion, and carbon emissions. And they have drawn normative moral and political conclusions from these scientific beliefs, such as that we should recognize the wisdom behind conservative values, like religiosity, patriotism, and puritanism, and that we should valorize a communitarian loyalty and sacrifice for the good of the group over an every-man-for-himself individualism.
I am often asked whether I agree with the new group selectionists, and the questioners are always surprised when I say I do not. After all, group selection sounds like a reasonable extension of evolutionary theory and a plausible explanation of the social nature of humans. Also, the group selectionists tend to declare victory, and write as if their theory has already superseded a narrow, reductionist dogma that selection acts only at the level of genes. In this essay, I’ll explain why I think that this reasonableness is an illusion. The more carefully you think about group selection, the less sense it makes, and the more poorly it fits the facts of human psychology and history.
Why does this matter? I’ll try to show that it has everything to do with our best scientific understanding of the evolution of life and the evolution of human nature. And though I won’t take up the various moral and political colorings of the debate here (I have discussed them elsewhere), it ultimately matters for understanding how best to deal with the collective action problems facing our species.
The first big problem with group selection is that the term itself sows so much confusion. People invoke it to refer to many distinct phenomena, so casual users may literally not know what they are talking about. I have seen “group selection” used as a loose synonym for the evolution of organisms that live in groups, and for any competition among groups, such as human warfare. Sometimes the term is needlessly used to refer to an individual trait that happens to be shared by the members of a group; as the evolutionary biologist George Williams noted,”a fleet herd of deer” is really just a herd of fleet deer. And sometimes the term is used as a way of redescribing the conventional gene-level theory of natural selection in different words: subsets of genetically related or reciprocally cooperating individuals are dubbed “groups,” and changes in the frequencies of their genes over time is dubbed “group selection.” To use the term in these senses is positively confusing, and writers would be better off referring to whichever phenomenon they have in mind.
In this essay I’ll concentrate on the sense of “group selection” as a version of natural selection which acts on groups in the same way that it acts on individual organisms, namely, to maximize their inclusive fitness (alternatively, which acts on groups in the same way it acts on genes, namely to increase the number of copies that appear in the next generation; I will treat these formulations as equivalent). Modern advocates of group selection don’t deny that selection acts on individual organisms; they only wish to add that it acts on higher-level aggregates, particularly groups of organisms, as well. For this reason, the theory is often called “multilevel selection” rather than “group selection.” This all sounds admirably ecumenical and nonreductionist, but my arguments will also apply to multilevel selection. I don’t think it makes sense to conceive of groups of organisms (in particular, human societies) as sitting at the top of a fractal hierarchy with genes at the bottom, with natural selection applying to each level in parallel ways.
First I’ll examine the idea that group selection is a viable explanation of the traits of human groups such as tribes, religions, cultures, and nations. Then I’ll turn to group selection as an explanation of the traits of individual humans, that is, the intuitions and emotions that make it possible for people to learn their culture and coexist in societies. (No one denies that such faculties exist.) Finally I’ll examine the empirical phenomena that have been claimed to show that group selection is necessary to explain human altruism…
The Race against Time: Pushing the limits of brain science could bring Canadian marathoners Olympic glory
June 26, 2012
REID COOLSAET is wide awake, sprawled the wrong way on his hotel bed so he can prop his legs up against the headboard. Outside the window, a strong breeze scuds briskly across Toronto’s Lake Shore Boulevard, along the very route he will be running in the morning. The gears of his mind spin restlessly, cranking out the mental arithmetic of kilometre splits for different paces and different scenarios. No Canadian marathoner has competed at the Olympics since 2000, but tomorrow several men are aiming for the London Olympic qualifying standard of two hours, eleven minutes, and twenty-nine seconds. And Coolsaet himself is aiming even higher, at Jerome Drayton’s national record of 2:10:09, set in 1975 — the oldest record in the books.
At thirty-two, Coolsaet has been a familiar presence at top Canadian races for a decade, his curly red hair and elbows-askew gait easy to pick out in any pack of front-runners. But his pursuit of the record will take him into new territory: he cannot afford to waste precious seconds by starting too slowly, or squander precious energy by setting out too fast. So he has been training for months with a pace of precisely 3:05 per kilometre over 42.2 kilometres in mind, drumming the required rhythm into his head and legs until it feels automatic. The race organizers have arranged a dedicated “rabbit,” a metronome-for-hire from Kenya whose only job is to help Coolsaet stick to this pace for as long as possible and then to drop out somewhere in the second half of the race. Far ahead, a phalanx of Kenyan and Ethiopian superstars will chase a time several minutes faster than the Canadian record, which is irrelevant to Coolsaet. His only adversary is the clock.
But something doesn’t feel quite right. Finally, he pulls out his earbuds, rolls out of bed, and pads downstairs to the hotel bar, where his long-time coach, Dave Scott-Thomas, is having a beer with other members of his support crew. “I need to talk,” he tells Scott-Thomas. The two retreat to the lobby, the tousle-haired coach towering over his diminutive charge, and find a pair of couches where they can sit undisturbed. Coolsaet gets right to the point: “I want to go out with the leaders tomorrow,” he says. “And I want you to tell me if that’s insane or not.”
Scott-Thomas is a methodical planner who has been grooming Coolsaet for this moment since 1998, first at the University of Guelph in Ontario, and then as part of the city’s Speed River Track and Field Club, each year pushing back the outer perimeter of the runner’s abilities in careful increments. But Scott-Thomas also knows that physiology alone does not determine race outcomes. “Sometimes we let our brains put too many riders on our own bodies,” he explains later. In fact, a wave of new research over the past few years has thrown into question the very existence of physical limits, as we currently understand them. Beneath Coolsaet’s apparent uncertainty, Scott-Thomas senses a seam of hard-earned confidence, so he gives the green light: “Why not? ” he says. “Go for it!” With months of strategizing abruptly discarded, Coolsaet heads upstairs, crawls back into bed, and within minutes falls fast asleep.
STRAPPED INTO what looks like a dentist’s chair, a muscular volunteer in short shorts and running shoes fights to straighten his right leg, which is held motionless in the viselike grip of a robotic clamp. Sweat beads on his forehead. On a nearby computer screen, the force generated by his quadriceps scrolls by in real time; four electromyograph sensors on a newly shaved patch of his leg simultaneously measure the electrical activity travelling from his brain to his muscles. “Come on, thirty seconds left!” yells Yumna Albertus-Kajee, the petite, usually soft-spoken postdoctoral researcher who runs the experiment. “Push it out! Push it out!”
Poke your head into any of the rooms along this corridor at the University of Cape Town’s Exercise Science and Sports Medicine research unit, and you will find more young volunteers being pushed to their limits in an endless variety of grimace-inducing ways: pedalling furiously, lifting, sprinting, or sweating in a heat chamber, all the while connected to panels of blinking, whirring electronics. Here, Albertus-Kajee’s boss, Tim Noakes, a controversial exercise physiologist whom some peg as the greatest of his generation, is building the case for a theory that would overturn almost a century of textbook physiology and reassert what generations of athletes have known in their bones: it is the brain that determines when we quit.
At sixty-two, Noakes has greying temples and a near-permanent grin. A competitive rower as an undergraduate, he only discovered running when a rowing practice was cancelled due to high winds. He decided to run around a nearby lake, and after forty minutes was overcome with a feeling of euphoria — the classic but elusive runner’s high. Thanks in part to this quirk of brain chemistry, he quickly became hooked on the new sport, and ultimately shifted his professional interests from clinical medicine to running-related research. His penchant for “paradigm rattling,” as one colleague refers to it, emerged early: in the 1980s, he was the first to identify the potentially fatal risks of drinking too much water during exercise, more than two decades before this was widely acknowledged. He also penned the enduring pop-sci classic Lore of Running, which earned him acclaim beyond the halls of academia.
In 1996, he received one of the highest honours in the field of exercise physiology: an invitation to deliver the J. B. Wolffe Memorial Lecture at the annual meeting of the American College of Sports Medicine. True to his reputation, he decided to harangue his eminent audience about the stubborn adherence to the “ugly and creaking edifices” of old theories that were unsupported by “empirical science.” As he prepared his talk, he had a crucial epiphany: “I said, now hold on. What is really interesting about exercise is not that people die of, say, heatstroke; or when people are climbing Everest, it’s not that one or two die,” he recalls. “The fact is, the majority don’t die — and that is much more interesting.”
Noakes proposed that the brain is wired to protect itself by pre-emptively shutting down your muscles before any part of your body reaches total failure. If your muscles are being depleted of oxygen and your heart is working too hard; or if you are becoming dangerously dehydrated; or if your core temperature is rising excessively; or if you are climbing a mountain and the amount of oxygen reaching your brain drops significantly — in all of these situations, a “central governor” in your brain acts to slow you down or stop you before you do irreversible damage. You stop not because you can’t physically go any farther, but because your brain thinks you shouldn’t.
Albertus-Kajee’s experiments illustrate how the brain applies the brakes before your muscles fail. The volunteer in the dentist’s chair (actually a high-tech force measurement tool called a dynamometer) is performing a two-minute maximal voluntary contraction test, pushing as hard as he can with his leg. The force produced by his muscles has steadily diminished over that period, as expected, but so has theEMG measurement of electrical activity. In essence, his brain is betraying him by requesting fewer and fewer muscle fibres in his leg to contract. When the two minutes finally end, he gets a scant five seconds of rest, and then Albertus-Kajee asks him to push again for just five more seconds. Amazingly, the force and EMG measurements spike back almost to their starting levels. Whatever caused the gradual decline in force, it could not have been the muscle fibres in his leg: they are still working fine.
That does not mean muscle fibres can keep contracting forever. If you take an isolated muscle from a frog, put it in a petri dish, and apply a jolt of electricity to it (as physiologists did in the first half of the twentieth century), the muscle will contract. And if you deliver that jolt repeatedly, the response will decrease and eventually stop: total muscle failure. Experiments like this, using isolated muscle tissue or brain-dead lab animals, produced the conventional understanding of muscle fatigue. The problem with this picture, points out Carl Foster, a professor at the University of Wisconsin–La Crosse and past president of the American College of Sports Medicine, is that “we are not decerebrate cats.” Instead, Noakes argues, our brains pick up distress signals from the muscle fibres and stop demanding contractions long before the fibres fail — an arrangement that just might leave us with some wiggle room…
This spring in Beijing, I asked a businessman an obvious question about the risks to China of an economic crash-landing, to which I got a less obvious reply. It is impossible to travel around China without concluding that the place is in the grip of a building frenzy. In less than a decade, China has pumped around $4 trillion into property; tens of millions of houses and apartments as well as Ozymandian public buildings and factory estates – and what hits the eye is how much of it all stands empty. Across the country, uninhabited concrete blocks scab the land, not only in the megacities of the eastern seaboard but also in the sleepier southwest; from filthy mining towns in Henan, all the way to entire ghost towns in Inner Mongolia. With an estimated 65 million homes standing vacant, residential construction last year was still running at a rate of five times demand.
Dwarfing even the $2 trillion borrowed for the Railway Ministry’s high-speed networks since 2008, and the thousands of kilometres of 4–6 lane toll roads with barely a vehicle on them, China’s building binge is the most striking example of what Prime Minister Wen Jiabao famously, but impotently, denounced in 2007 as the country’s “unbalanced, unstable, uncoordinated and unsustainable” model of economic development. Now, with house prices and sales sagging in response to government restrictions aimed at deflating history’s biggest ever property bubble, and with local governments as deep in bad debt as the developers, I asked the businessman what was to prevent the bubble actually bursting, in a spectacular financial explosion?
His answer was that it wouldn’t happen. A lot of these empty apartments, he said, had been bought by Chinese families as investments, and they would patiently hang on to these speculative purchases because interest on savings was derisory. Secondly, although some developers would go to the wall, the bubble would simply not be allowed to burst for fear of public anger as well as economic chaos. China had massive reserves if need arose, he said, and would not hesitate to bundle nonperforming loans off into a state “bad bank”. Its plans to build 36 million “affordable” homes by 2015 would also help to offset faltering private sector demand. When in a hole, in other words, the Party keeps digging.
Then the businessman added: “Look, I don’t lose too much sleep over China’s economic troubles; but I do worry, tremendously, about a political explosion tearing the place apart”. The dramatic political destruction in March of Bo Xilai, one of China’s most thrustingly ambitious and charismatic regional Communist Party bosses, has set off that explosion. The shockwaves are convulsing China at a crucial political juncture.
In October, the quinquennial Party Congress is due to approve a carefully contrived transfer of power, over party, government and the military, to a new generation of leaders – the first for a decade, and only the fourth since the Communist revolution in 1949. Bo had been expected to secure one of the nine seats on the Politburo Standing Committee, which along with the Central Military Committee exercises supreme power – thus putting him in a strong position to push his neo-Maoist agenda of reinforcing the state’s powers. Ever since Deng Xiaoping set out to transform China after Mao Zedong’s death in 1976, these handovers have been meticulously choreographed to reinforce a myth of political continuity and, above all, the façade of party unity. However tense the factional jostling may be, rivalries have been kept out of sight: President Hu Jintao’s “harmonious society” reserves back-stabbing for moonless nights.
This obsession with a seamless changing of the guard is rooted in China’s bitter history of abrupt and violent change, and most immediately in the chaos, suffering and abject fear the great mass of Chinese endured under Mao Zedong. Whether or not the people are fooled by the parade of unity – and more and more Chinese know how to read between the lines – the Party Congress also serves to emphasize that the exercise of power in China is not for mere mortals. But now, with the purging of Bo, a ferocious ideological battle has very publicly been joined by those who hold power. It goes far beyond personalities. Its outcome will determine China’s future direction – whether it reverts to a more statist path, or buttresses the market with political and legal reforms.
This is one of the climacterics to which China is historically prone, comparable in intensity and importance to the ideological confrontations that Mao Zedong suppressed by launching the Great Proletarian Cultural Revolution in 1966, and the ferment after his death. It brings to a head a long-simmering conflict between two opposing visions of China, artificially yoked together in Deng Xiaoping’s formula of opening up the economy while continuing to suppress political and intellectual freedoms. The more China modernizes, the less tenable that balancing act becomes between the Maoist past and the demands of governing an increasingly sophisticated, irreverent and politically literate society.
“Opening up” without accountability and the rule of law has produced the worst excesses of crony capitalism, rampant corruption, gross misallocation of resources, outrageous inequality, with corresponding public anger, distrust and contempt. Within the Party, there is a crisis of legitimacy, reflected in an obsession with “stability” that sees a threat in every dissenting voice, a risk in every reform. China’s internal security budget is now bigger even than its military expenditure, as the Party wrestles with the upsurge of what it euphemistically terms “mass incidents”. Nearly 200,000 protests against injustice and abuses of power, some large-scale and violent, are expected this year. The Chinese air is fouled, literally by pollution and figuratively by the Party’s moral and intellectual decay…
June 26, 2012
This image has been posted with express written permission. This cartoon was originally published at Town Hall.