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This Explains Everything

Page 14

by Mr. John Brockman


  ALL WE NEED IS HELP

  SEIRIAN SUMNER

  Research fellow in the evolution of sociality, Institute of Zoology, Zoological Society of London

  I play this game with my kids. It’s a “Guess who?” game: Think of an animal, person, or object, and then try to describe it to another person without giving away the identity. The other person has to guess what/who you are. You have to get in character and tell a story: What do you do, how do you feel, what do you think and want?

  Let’s have a go. Read the character scenarios below and see if you can guess who/what they are.

  “It’s just not fair! Mum says I’m getting in the way, I’m a layabout, and she can’t afford for me to stay with her anymore. But I like being in a big family, and I don’t want to leave. Why take the risk of leaving home? Who knows what lies out there! Mum says that if I am to stay home, we’d need some kind of ‘glue’ to keep us from drifting apart. Now, glue is costly, and she says she hasn’t the time or energy to make it, since she’s busy making babies. But then I had this brilliant idea: How about I make the glue, using a bit of cell wall (Mum won’t mind), add some glycoproteins (they’re a bit sticky, so I have to promise Mum I’ll wash my hands afterward), and bingo! Job done: We’ve got ourselves a nice cosy extracellular matrix! I’m happy doing the bulk of the work, so long as Mum keeps giving me more siblings. I suggested this to Mum last night, and guess what? She said yes! But she also said I’m out the door if I don’t keep up my side of the bargain. No free-riders. . . .”

  Who am I? I am a unicell becoming multicellular. If I group with my relatives, then someone needs to pay the cost of keeping us together—the extracellular matrix. I don’t mind paying that cost if I benefit from the replication of my own genes through my relatives.

  OK, that’s a tough one. Try this one:

  “I’m probably what you’d call the maternal type. I like having babies, and I’ve probably already had too many this year—at least that’s what my children tell me. But I seem to be pretty good at it. I love them all equally, obviously. Damn hard work, though, especially since their father didn’t stick around. Interested in only one thing, he was, and off in a flash. But I can’t see my latest babies surviving unless I get some help around the place—all these mouths to feed, no time to clear up the place. So I said to my oldest the other day, ‘How’s about it, kid? Fancy helping your old ma out around the place a bit? Here’s the deal: You go find some food while I just squeeze out a few more siblings for you. Remember, kid, I’m doing this for you—all these siblings I’m making, it’ll pay off in the long run. One day, one of them will be a ma just like me—imagine that! And you’ll still be reaping the benefits from her, too, long after you and I are gone. This way you don’t ever have to worry about sex, men, or any of that sperm stuff. Your old ma’s got everything you need, right here. All you have to do is feed us and clear out the mess. There’s a good kid—off you go, but don’t talk to strangers, especially men!’ ”

  Who am I? I am an insect becoming a society. If I nest alone, I have to find food, which means leaving my young unprotected. If some of my grown-up children stay home and help me, they can go out foraging, leaving me to defend the young. I can have even more babies this way, which my children love, as this means more and more of their genes are passed on through their siblings. Anyway, it’s a pretty tough world out there right now for youngsters. It’s much less risky to stay at home.

  A little tweaking of the details in the above sketches and I could equally be a gene becoming a genome, or a prokaryote becoming a eukaryote. I am part of the same fundamental event in evolution’s playground. I am the evolution of helping and cooperation. I am the major transition that shapes all levels of biological complexity. The reason I happen is because I help others like me, and we agree on a division of labor (OK, there are some fights, but we balance conflict with cooperation, and sometimes a little coercion doesn’t go amiss). And the reason I help is not because it makes me feel good but because, paradoxically, I benefit from helping. My secret? I’m pretty selective: I like to help my relatives, because they end up also helping me, by passing on our shared genes. I’ve embraced the transition from autonomy to cooperation, and it feels good!

  The evolution of cooperation and helping behavior is a beautiful and simple explanation for how nature got complex, diverse, and wonderful. It’s not restricted to the charismatic meerkats or the fluffy bumblebees. It’s a general phenomenon that sweeps across the good, bad, and ugly sides of nature, generating the biological hierarchies that characterize the natural world. Groups of individuals (genes, prokaryotes, single-celled and multicellular organisms) that could previously replicate independently come together to form new, more complex individuals in their own right. This new collective individual can replicate only as a whole. Take each component in isolation and it is unable to function or pass genes on to the next generation.

  The simplest, most elegant rule in the natural world explains why this complexity evolves: William Hamilton’s 1964 inclusive-fitness theory, which encompasses the essence of natural selection. Entities cooperate because it increases their fitness—their chance of passing on genes to the next generation. Receivers of help benefit from enhanced personal reproduction—direct fitness. Helpers benefit from the propagation of the genes they share with the relatives they help—indirect fitness. We still have solitary insects, single-celled organisms, and prokaryotes, because the conditions need to be right for division of labor to evolve: The benefits must outweigh the costs, and this sum is affected by the options available to independent replicating entities. Ecology and environment play a role, as well as kinship. The resulting division of labor is the fundamental basis of societal living, uniting genes into genomes, uniting mitochondria and prokaryotes to produce eukaryotes, uniting unicellular organisms into multicellular ones and solitary animals into eusocieties. Without the evolution of helping and division of labor, there would be no eukaryotes, no multicellular organisms, no animal societies—in short, our planet would be barren and dull.

  We have understood this simple concept for almost half a century now. It’s only very recently, however, that we have realized that the evolution of helping explains not just the transition to eusociality in insects (for which Hamilton originally developed the theory) but also the evolution of major transitions to biological complexity in general. Among others, Andrew Bourke produced an insightful synthesis of this unified framework for the origins of biological complexity in his recent book Principles of Social Evolution. This satisfyingly simple explanation makes the complexities of the world less mysterious but no less wonderful.

  If only adults played children’s games more often, perhaps we’d stumble across other simple explanations for the complexities of life.

  IN THE BEGINNING IS THE THEORY

  HELENA CRONIN

  Codirector of the London School of Economics’ Centre for Philosophy of Natural and Social Science; author, The Ant and the Peacock: Altruism and Sexual Selection from Darwin to Today

  Let’s eavesdrop on an exchange between Charles Darwin and Karl Popper. Darwin, exasperated at the crass philosophy of science peddled by his critics, exclaims, “How odd it is that anyone should not see that all observation must be for or against some view if it is to be of any service!”* And when the conversation turns to evolution, Popper observes, “All life is problem solving,” noting that “from the amoeba to Einstein, the growth of knowledge is always the same.”*

  There is a confluence in their thinking. Though traveling by different pathways, they arrived at the same insight. It has to do with the primacy and fundamental role of theories—of ideas, hypotheses, perspectives, views, dispositions, and the like—in the acquisition and growth of knowledge. Darwin was right to stress that such primacy is needed “if [the observation] is to be of any service.” But the role of a “view” also goes far deeper. As Darwin knew, it is impossible to observe at all without some kind of view. If you are unconvinced, try
this demonstration, one that Popper liked to use in lectures. “Observe!” Have you managed that? No. Because, of course, you need to know, “Observe what?” All observation is in the light of some theory; all observation must be in the light of some theory. So all observation is theory-laden—not sometimes, not contingently, but always and necessarily.

  This is not to depreciate observation, data, facts. On the contrary, it gives them their proper due. Only in the light of a theory, a problem, the quest for a solution, can they speak to us in revealing ways.

  Thus the insight is immensely simple. But it has wide relevance and great potency. Hence its elegance and beauty.

  Here are two examples, first from Darwin’s realm, then from Popper’s.

  • Consider the tedious but tenacious argument: “genes vs. environment.” I’ll take a well-studied case. Indigo buntings migrate annually over long distances. To solve the problem of navigation, natural selection equipped them with the ability to construct a mental compass by studying the stars in the night sky, boy-scout fashion, during their first few months of life. The fount of this spectacular adaptation is a rich source of information that natural selection, over evolutionary time, has packed into the birds’ genes—in particular, information about the rotation of the stellar constellations. Thus buntings that migrate today can use the same instincts and the same environmental regularities to fashion the same precision-built instrument as did their long-dead ancestors.

  And all adaptations work in this way. By providing the organism with innate information about the world, they open up resources for the organism to meet its own distinctive adaptive needs; thus natural selection creates the organism’s own tailor-made, species-specific environment. And different adaptive problems therefore give rise to different environments; so different species, for example, have different environments.

  Thus what constitutes an environment depends on the organism’s adaptations. Without innate information, carried by the genes, specifying what constitutes an environment, no environments would exist. And thus environments, far from being separate from biology, autonomous and independent, are themselves in part fashioned by biology. Environment is therefore a biological issue, an issue that necessarily begins with biologically stored information.

  But aren’t we anyway all interactionists now—no longer genes vs. environment but gene/environment interaction? Yes, of course; interaction is what natural selection designed genes to do. Bunting genes are freighted with information about how to learn from stars because stars are as vital a part of a bunting’s environment as is the egg in which it develops or the water it drinks. Buntings without stars are destined to be buntings without descendants. But interaction is not parity; the information must come first. Just try this parity test. Try specifying “an” environment without first specifying whether it is the environment of a bunting or a human, a male or a female, an adaptation for bird navigation or for human language. The task is impossible; the specification must start from the information stored in adaptations. And here’s another challenge to parity. Genes use environments for a purpose: self-replication. Environments, however, have no purposes; so they do not use genes. Thus bunting genes are machines for converting stars into more bunting genes; but stars are not machines for converting bunting genes into more stars.

  • The second example has to do with the notion of objectivity in science. Listen further to Darwin’s complaint about misunderstandings over scientific observation: “How profoundly ignorant [this critic] must be of the very soul of observation! About thirty years ago, there was much talk that geologists ought only to observe and not theorise; and I well remember some one saying that at this rate a man might as well go into a gravel-pit and count the pebbles and describe the colours.”*

  One hundred and fifty years later, variants of that thinking still stalk science. Consider the laudable but now somewhat tarnished initiative to establish evidence-based policymaking. What went wrong? All too often, objective evidence was taken to be data uncontaminated by the bias of a prior theory. But without “the very soul” of a theory as guidance, what constitutes evidence? Objectivity isn’t to do with stripping out all presuppositions. Indeed, the more that’s considered possible or desirable, the greater the undetected, uncriticized presuppositions and the less the objectivity. At worst, a desired but unstated goal can be smuggled in at the outset. And the upshot? This well-meant approach is often justifiably derided as “policy-based evidence-making.”

  An egregious example from my own recent experience, which still has me reeling with dismay, was from a researcher on “gender diversity” whose concern was discrimination against women in the professions. He claimed that his research was absolutely free of any prior assumptions about male/female differences and that it was therefore entirely neutral and unbiased. If any patterns of differences emerged from the data, his neutral, unbiased assumption would be that they were the result of discrimination. So might he accept that evolved sex differences exist? Yes, if it were proven. And what might such a proof look like? Here he fell silent, at a loss—unsurprisingly, given that his “neutral” hypotheses had comprehensively precluded such differences at the start. What irony, that in the purported interests of scientific objectivity he ostensibly felt justified in clearing the decks of the entire wealth of current scientific findings.

  The Darwin-Popper insight, in spite of its beauty, has yet to attract the admirers it deserves.

  THOMPSON ON DEVELOPMENT

  PAUL BLOOM

  Brooks and Suzanne Ragen Professor of Psychology & Cognitive Science, Yale University; author, How Pleasure Works

  “Everything is the way it is because it got that way.” This aphorism is attributed to the biologist and classicist D’Arcy Thompson, and it’s an elegant summary of how Thompson sought to explain the shapes of things, from jellyfish to sand dunes to elephant tusks. I saw this quoted first in an Edge discussion by Daniel Dennett, who made the point that this insight applies to explanation more generally—all sciences are, to at least some extent, historical sciences.

  I think it’s a perfect motto for my own field of developmental psychology. Every adult mind has two histories. There is evolution; few would doubt that some of the most elegant and persuasive explanations in psychology appeal to the constructive process of natural selection. And there is development—how our minds unfold over time, the processes of maturation and learning.

  While evolutionary explanations work best for explaining what humans share, development can sometimes capture how we differ. This may be obvious: Nobody is surprised to hear that adults who are fluent in Korean have usually been exposed to Korean when they were children, or that adults who practice Judaism have usually been raised as Jews. But other developmental explanations are rather interesting.

  There is evidence that an adult’s inability to see in stereo is due to poor vision during a critical period in childhood. Some have argued that the self-confidence of adult males is influenced by how young they were when they reached puberty (because of the boost in status caused by being bigger, even if temporarily, than their peers). It has been claimed that smarter adults are more likely to be firstborns (because later children find themselves in environments that are, on average, less intellectually sophisticated). Creative adults are more likely to be later-borns (because they were forced to find their own distinctive niches). Romantic attachments in adults are influenced by their relationships as children with their parents. A man’s pain-sensitivity is influenced by whether or not he was circumcised as a baby.

  With the exception of the stereo-vision example, I don’t know if any of these explanations are true. But they are elegant and non-obvious, and some of them verge on beautiful.

  HOW DO YOU GET FROM A LOBSTER TO A CAT?

  JOHN McWHORTER

  Linguist; senior fellow, Manhattan Institute for Policy Research; author, What Language Is (And What It Isn’t and What It Could Be)

  Did you ever notice that the “vein” you
are told to remove from shrimp before eating them doesn’t seem to ooze anything you’d be inclined to call blood? Doesn’t the slime seem more like some sort of alimentary waste? That’s because it is. In shrimp, you can get at the digestive system right through its back, because that’s where it is. The heart’s up there too, and this is the way it is in arthropods, the animal phylum that includes crustaceans and insects. Meanwhile, if you were interested in finding the shrimp’s main nerve highway, you’d find it running down along its bottom side.

  That seems backwards to us, because we’re chordates, another big animal phylum. Chordates have the spinal nerve running down the back, with the heart and gut in front. It’s as if our body plans were mirror images of arthropods’, and this is a microcosm of a general split between larger classes. Arthropods are among the protostomes, with the guts on the back, as opposed to the deuterostomes that we chordates are among, with the guts up front.

  Biologists have noticed this since auld lang syne, with naturalist Étienne Geoffroy Saint-Hilaire turning a dissected lobster upside down and showing that as such, its innards’ arrangement resembled ours. The question was how things got this way, especially as Darwin’s natural-selection theory became accepted. How could one get step-by-step from the guts on the back and the spinal cord up front to the reverse situation? More to the point, why would this be evolutionarily advantageous, which is the only reason we assume it would happen at all?

 

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