THE DEVIL UNDER FORM OF BABOON: THE EVOLUTION OF EVOLUTIONARY ETHICS
Our descent, then is the origin of our evil passions!!—The Devil under form of Baboon is our grandfather!
—Chades Darwin, M Notebook, 1838
In a poetic form of authorial acknowledgment, Jonathan Swift famously gave the nod to those who came before him with this poem, a favorite among naturalists:
So, naturalists observe, a flea
Hath smaller fleas that on him prey;
And these have smaller still to bite ’em
And so proceed ad infinitum.
Thus every poet, in his kind,
Is bit by him that comes behind.
We are all bit by those behind us, but nowhere is this clearer than in the tradition of science because of its cumulative and progressive nature of building on those who came before. “If I have seen further it is by standing on ye shoulders of Giants,” Sir Isaac Newton even more famously observed. The quote is itself part of a long historical tradition dating at least to the fourteenth-century scholar Bernard of Chartres, in reference to New Testament prophets standing on the shoulders of Old Testament prophets (as depicted in stone in one of the transepts of Chartres Cathedral): “We are like dwarfs seated on the shoulders of giants; we see more things than the ancients and things more distant. But this is due neither to the sharpness of our own sight, nor to the greatness of our own stature, but because we are raised and borne aloft on that giant mass.”1
The first half of this book, entitled “The Origins of Morality,” was built on the theory of evolutionary ethics, a study that began in the late 1830s when, among his scattered thoughts on the implications for his budding evolutionary hypothesis, Charles Darwin penned this muse in his M Notebook (opened shortly after returning home from a five-year voyage around the world): “He who understands baboon would do more towards metaphysics than Locke.” Biology, Darwin believed, not philosophy, is where we might find insights into our moral (not to mention our immoral) natures: “Our descent, then is the origin of our evil passions!!—The Devil under form of Baboon is our grandfather!”2
Darwin’s founding of the study of evolutionary ethics belongs to a long tradition of ethical naturalism that dates back twenty-five centuries to Aristotle and eight centuries to Thomas Aquinas. Aquinas defined “natural law” as “that which nature has taught all animals”; thus, moral law must be rooted in the natural inclinations of the human animal. Because Darwin’s biological explanation of morality was grounded in such natural inclinations, this has been called “Darwinian natural right.”3 Morality is subsumed under the umbrella of human nature, just one of a pantheon of thoughts and behaviors legitimately targeted as subjects of study within the natural sciences. Morality—as an expression of human thought and behavior related to the judgment and evaluation of one’s own and others’ thoughts and behaviors—can be explored and examined by psychologists, anthropologists, evolutionary psychologists, and other social scientists in the same manner that political beliefs, social attitudes, religious faith, and other human expressions of thought can be studied.4
Charles Darwin, then, was the first evolutionary psychologist and ethicist. In his 1871 book The Descent of Man, he made this logical inference from the data produced by zoology and anthropology: “The following proposition seems to me in a high degree probable—namely, that any animal whatever, endowed with well marked social instincts, the parental and filial affections being here included, would inevitably acquire a moral sense or conscience, as soon as its intellectual powers had become as well, or nearly as well developed, as in man.” Even though it was Darwin, more than anyone else, who demonstrated that humans are animals too, it was the moral sense—of all our exalted characteristics—that separates us from all other animals: “I fully subscribe to the judgment of those writers who maintain that of all the differences between man and the lower animals, the moral sense or conscience is by far the most important.”5 The evolution of the moral sense was a step-by-step process, aided by the same emotions generated by religious rituals and expressions, that would result in “a highly complex sentiment, having its first origin in the social instinct, largely guided by the approbation of our fellow-men, ruled by reason, self-interest, and in later times by deep religious feelings, confirmed by instruction and habit, all combined, constitute our moral sense and conscience.”6
Ever since Darwin the science of evolutionary ethics has waxed and waned, roughly passing through five stages: (1) Origins—from Darwin to the end of the First World War; (2) Synthesis—from the beginning of the modern synthesis of evolutionary theory in the 1920s through the mid-1970s; (3) Controversy—from the birth of sociobiology in 1975 to the early 1990s; (4) Victory—from the triumph of evolutionary psychology in the early 1990s to 2000; and (5) Consolidation—the incorporation of group selection and hierarchical evolutionary theory from 2000 to the present. While my historical summation of the first three stages is descriptive, the last two are prescriptive. That is, although historians of science will not find much to quibble with in my description of the field’s origins, synthesis, and controversy, many scientists will disagree with my prescription of victory and consolidation.
Origins
In Charles Darwin’s time there was no one more enthusiastic about applying natural selection than its codiscoverer Alfred Russel Wallace. Yet, in my biography of Wallace, In Darwin’s Shadow, I argue that his purist mode of hyperselectionist thinking and his commitment to scientism led him, ironically, to conclude that natural selection cannot account for the human brain and morals. Like Darwin before him, Wallace minced no words about why humans and animals are different: “My view … was, and is, that there is a difference in kind, intellectually and morally, between man and other animals.”7 That difference, however, was not generated by natural selection, but was instead, Wallace concluded, the product of a higher intelligence because he could think of no possible reason nature would have selected for such a large and varied organ. He said as much in an article on “The Limits of Natural Selection as Applied to Man”:
In the brain of the lowest savages and, as far as we know, of the prehistoric races, we have an organ … little inferior in size and complexity to that of the highest types … . But the mental requirements of the lowest savages, such as the Australians or the Andaman Islanders, are very little above those of many animals. How then was an organ developed far beyond the needs of its possessor? Natural Selection could only have endowed the savage with a brain a little superior to that of an ape, whereas he actually possesses one but very little inferior to that of the average members of our learned societies.8
Therefore, Wallace concluded, “an Overruling Intelligence has watched over the action of those laws, so directing variations and so determining their accumulation, as finally to produce an organization sufficiently perfect to admit of, and even to aid in, the indefinite advancement of our mental and moral nature.”9 How did this evolution come about? Wallace argued that natural selection operated on the physical body of man long before a mind with consciousness existed. The races, represented by a “protoman,” were fully developed physically before civilization began. Once the brain reached a certain level, however, natural selection would no longer operate on the body; man could now manipulate his environment. The creation of mind had lessened the effectiveness of natural selection (and therefore the process of evolution). Ironically, a propensity toward cooperation and mutual aid may have played a role in this attenuation: “In the rudest tribes the sick are assisted, at least with food; less robust health and vigour than the average does not entail death. The action of natural selection is therefore checked; the weaker, the dwarfish, those of less active limbs, or less piercing eyesight, do not suffer the extreme penalty which falls upon animals so defective.”10
With this alteration of natural law, Wallace argued, came a shift from individual to group selection. While individuals would be protected by the group from the ravages of nature, groups themselves might continue evolving, especially those with high intelligence, foresight, sympathy, a sense of right, and self-restraint: “Tribes in which such mental and moral qualities were predominant would therefore have an advantage in the struggle for existence over other tribes in which they were less developed—would live and maintain their numbers, while the others would decrease and finally succumb.”11 Wallace argued that the harsher, more challenging climate of northern Europe had produced “a hardier, a more provident, and a more social race” than those from more southern climates. Indeed, he pointed out, European imperialism, particularly the British form, was causing whole races to disappear “from the inevitable effects of an unequal mental and physical struggle.”12 Ever the grand synthesizer, Wallace ends his argument with a flare of teleological purposefulness and an egalitarian hope for the future of humanity shaped via human-controlled group selection:
If my conclusions are just, it must inevitably follow that the higher—the more intellectual and moral—must displace the lower and more degraded races; and the power of ‘natural selection,’ still acting on his mental organisation, must ever lead to the more perfect adaptation of man’s higher faculties to the conditions of surrounding nature, and to the exigencies of the social state. While his external form will probably ever remain unchanged, except in the development of that perfect beauty which results from a healthy and well organised body, refined and ennobled by the highest intellectual faculties and sympathetic emotions, his mental constitution may continue to advance and improve, till the world is again inhabited by a single nearly homogeneous race, no individual of which will be inferior to the noblest specimens of existing humanity.13
One of Alfred Wallace’s intellectual heroes was the philosopher, social scientist, and social Darwinist Herbert Spencer. So enamored of Spencer was Wallace that he named his firstborn son Herbert Spencer Wallace. Thus, we should not be surprised to know that their ideas on evolutionary theory, in particular evolutionary ethics, were well in accord. When Spencer read Wallace’s 1864 paper “The Origin of the Races of Man” (quoted above), for example, Spencer immediately wrote Wallace and told him: “Its leading idea is, I think, undoubtedly true, and of much importance towards an interpretation of the facts … . I think it is quite clear, as you point out, that the small amounts of physical differences that have arisen between the various human races are due to the way in which mental modifications have served in place of physical ones.”14 In 1879 Wallace wrote to Spencer: “I doubt if evolution alone, even as you have exhibited its action, can account for the development of the advance and enthusiastic altruism that not only exists now, but apparently has always existed among men.” But Spencer did not always go far enough for Wallace in speculating about the origins of morality: “If on this point I doubt, on another point I feel certain, and that is, not even your beautiful system of ethical science can act as a ‘controlling agency’ or in any way ‘fill up the gap left by the disappearance of the code of supernatural ethics.’” 15
Spencer was actually ahead of both Darwin and Wallace in attempting a scientific analysis of ethics (even if it was not a strictly evolutionary one) when he published, in 1851, Social Statics; or The Conditions Essential to Human Happiness Specified, and the First of Them Developed . This was not so much a descriptive theory on the origins of morality as it was a prescriptive theory on how morality should be applied to society in a rational and scientific manner. Spencer rejected utilitarian calculations of the greatest good for the greatest number. Instead, Spencer postulated, “the moral law of society, like its other laws, originates in some attribute of the human being.” Although he called it science, Spencer was really doing philosophy, making his case through logical deduction rather than empirical facts, beginning with a divine origin of morality: “God wills man’s happiness. Man’s happiness can only be produced by the exercise of his faculties. Then God wills that he should exercise his faculties. But to exercise his faculties he must have liberty to do all that his faculties naturally impel him to do. Then God intends he should have that liberty. Therefore he has a right to that liberty.” From this it follows that “All are bound to fulfill the Divine will by exercising them. All therefore must be free to do those things in which the exercise of them consists. That is, all must have rights to liberty of action.” Of course, my freedom to swing my arm in any direction I choose ends at your nose. Spencer deduced this, of course, concluding, “Every man has freedom to do all that he wills, provided he infringes not the equal freedom of any other man.”16
Spencer, as an editor of the magazine The Economist, was familiar with and accepted Adam Smith’s theory that humans had the mental capacity for sympathy. Smith, before The Wealth of Nations made him the fountainhead of classical liberal free-market economics, was a professor of moral philosophy who argued that the foundation of morality was based on the ability we have to put our self in someone else’s shoes. When you see someone grieving, you feel sympathy because you can project yourself into that situation and imagine how you would feel. An anticipation of self-grief generates genuine sympathy for the other person. In 1879 Spencer published The Data of Ethics, and in 1891 his Principles of Ethics, in which he abandoned supernatural intervention as a causal factor in the origins of morality and turned enthusiastically to Darwinian selection:
We have to enter on the consideration of moral phenomena as phenomena of evolution; being forced to do this by finding that they form a part of the aggregate of phenomena which evolution has wrought out. If the entire visible universe has been evolved—if the solar system as a whole, the earth as a part of it, the life in general which the earth bears, as well as that of each individual organism—if the mental phenomena displayed by all creatures, up to the highest, in common with the phenomena presented by aggregates of these highest—if one and all conform to the laws of evolution; then the necessary implication is that those phenomena of conduct in these highest creatures with which Morality is concerned, also conform .17
While Spencer was arguably the most influential evolutionary ethicist outside of Darwin in the nineteenth century, he was not without strong critics, not the least of which was “Darwin’s bulldog,” Thomas Henry Huxley. Huxley was skeptical about how far evolutionary theory could be extended into the realm of ethics, but not for the same reason as Wallace, who questioned what selective advantage a system of ethics would have conferred on an individual or species. Instead, Huxley doubted that nature could be an ethical guide for us at all: “Cosmic evolution may teach us how the good and the evil tendencies of man may have come about; but, in itself, it is incompetent to furnish any better reason why what we call good is preferable to what we call evil than we had before.” In one of the most powerful one-liners in the history of evolutionary thought (at least as it relates to ethics), Huxley definitely came down hard on the reality of what he saw as our brutal nature: “Let us understand, once for all, that the ethical process of society depends, not on imitating the cosmic process, still less in running away from it, but in combating it.”18
After the initial excitement of evolutionary ethics wore off, its influence on both the public and academic philosophers and natural scientists faded into near oblivion. By the turn of the century the theory of evolution itself was experiencing something of a decline; scientists were openly expressing skepticism that natural selection could do all that Darwin said it could. Cambridge University philosopher G. E. Moore was especially contemptuous of evolutionary ethics, attacking it on the grounds that it violated the “naturalistic fallacy,” mistakenly inferring the ought from the is, or prescribing the way things should be based on a description of the way things are. The “good,” said Moore in his classic Principia Ethica, cannot be quantified like the utilitarians tried to do, nor could it be analyzed for its evolutionary adaptiveness. In fact, it cannot be defined by reference to some “other thing.” Its existence had to be apprehended on its own without outside reference.19 Synthesis
By World War I, the study of evolutionary ethics was in serious decline. But as it moved into its second phase between the wars, Julian Huxley and C. H. Waddington revised it—in conjunction with the modern evolutionary synthesis. Julian Huxley reinvigorated evolutionary ethics by grafting it onto the larger intellectual and social movement known as humanism. Huxley, in fact, called himself a religious humanist, “but without belief in any personal God.” Like his grandfather Thomas, Julian cared not at all for traditional religion and did not believe in God, but unlike the senior Huxley, Julian rejected Moore’s charges, arguing that science can not only tell us the way things are, it can direct us toward the way things ought to be:
In the broadest possible terms evolutionary ethics must be based on a combination of a few main principles: that it is right to realize ever new possibilities in evolution, notably those which are valued for their own sake; that it is right both to respect human individuality and to encourage its fullest development; that it is right to construct a mechanism for further social evolution which shall satisfy these prior conditions as fully, efficiently, and as rapidly as possible.20
Like Wallace, Julian Huxley’s evolutionary ethics was based on a belief in the progressive nature of evolution, although he did not envision a socialist utopia as an ideal state. He shared with his grandfather an enthusiasm for science and evolutionary thinking, but his vision of ethics was far less combative against nature than Thomas Huxley’s was. As Julian wrote:
When we look at evolution as a whole, we find, among the many directions which it has taken, one which is characterized by introducing the evolving world-stuff to progressively higher levels of organization and so to new possibilities of being, action, and experience. This direction has culminated in the attainment of a state where the world-stuff (now moulded into human shape) finds that it experiences some of the new possibilities as having value in or for themselves; and further that among these it assigns higher and lower degrees of value, the higher values being those which are more intrinsically or more permanently satisfying, or involve a greater degree of perfection.21
The latter half of this second renaissance for evolutionary ethics saw it fade once again after the Second World War. This second waning was a result, in part, of an extreme antihereditarianism view in psychology and the social sciences—an understandable response to Nazi eugenics, ethnic cleansing, and especially the Holocaust. As a consequence, however, scientists steered clear of the study of the biological and evolutionary origins of morality, instead focusing on purely cultural explanations. It was a trend mirrored throughout the social sciences and humanities, as scientists and scholars began with a prima facie assumption that social and psychological behavior must primarily be influenced by the environment, not biology.
Controversy
Evolutionary ethics lay dormant for three decades until 1975 when Harvard evolutionary biologist Edward O. Wilson published his 700-page magnum opus, Sociobiology: The New Synthesis. Ironically, only the final chapter deals with humans (“Man: From Sociobiology to Sociology”), and only in one short section—barely two pages long—does the reader encounter ethics and its possible evolutionary origins. But what is said, when it is said, and who is doing the saying matters as much in science as it does in other human endeavors, and here is what Wilson said: “Scientists and humanists should consider together the possibility that the time has come for ethics to be removed temporarily from the hands of the philosophers and biologicized.”22 Like Darwin’s single line at the end of The Origin of Species—“light will be thrown on the origin of man and his history” (later editions added the modifier “much”)—Witson’s one-liner fired a shot heard ’round the intellectual world. Academic philosophers were incensed that an outsider was encroaching on their turf and doing so in such cold scientific jargon: “Ethical philosophers intuit the deontological canons of morality by consulting the emotive centers of their own hypothalamic-limbic system,” he wrote in Sociobiology reducing thousands of years of philosophy to mere speculation on hormonally driven internal states. “Only by interpreting the activity of the emotive centers as a biological adaptation can the meaning of the canons be deciphered.”23 Wilson was vilified in the press, despite his disclaimer at the end of that brief section: “It should also be clear that no single set of moral standards can be applied to all human populations, let alone all sex-age classes within each population. To impose a uniform code is therefore to create complex, intractable moral dilemmas—these, of course, are the current condition of mankind.”24
At stake in this battle—now known as the “evolution wars”—is nothing less than how human societies and families should be structured, how parents should raise children, how criminals should be handled, among other issues related to the nature of human nature. Also on the line, as the sociologist Ullica Segerstrale observed in her encyclopedic history of the evolution wars—Defenders of the Truth—is “the soul of science.”25
The story of how an academic textbook by an entomologist could result in one of the most rancorous debates in all of science begins with the reactions to Wilson and his theory by his Harvard colleagues Stephen Jay Gould and Richard Lewontin. Their Sociobiology Study Group, along with the politically charged, left-leaning organization Science for the People, were involved in the now famous incident at the 1978 meeting of the American Association for the Advancement of Science in the Sheraton Park Hotel in Washington, D.C. When Wilson advanced to the podium, demonstrators chanted, “Racist Wilson you can’t hide, we charge you with genocide!” Someone leaped up on the dais, grabbed a cup of ice water, and dumped it on Wilson’s head, shouting, “Wilson, you are all wet!” This was too much even for Stephen Jay Gould, who admonished the demonstrators, telling them their actions were what Lenin had dismissively called “Infantile Leftism.” The infamously bellicose anthropologist Napoleon Chagnon wasted no time in coming to Wilson’s defense, grabbing one of the attackers and tossing him from the stage.
Why, Wilson wondered two decades later in his autobiographical book Naturalist, didn’t Gould and Lewontin just come up to his office from theirs (one floor below in the same Harvard building) to discuss their concerns? Why attack him in the very public pages of the New York Review of Books when this all could have been handled in private? The reason is that science is not the private and always-rational enterprise it is often made out to be. Why, Gould and Lewontin could just as easily have asked, didn’t Wilson come down one floor to their offices to discuss with them in private his ideas about applying principles of animal behavior to human societies? The answer is the same: if you want to get your theories out into the marketplace of ideas, you cannot sequester them in your office. You’ve got to make them public, and the more public the better. Hashing the debate out in public gives you the forum you would never get in private. (An analogy here will help. On March 14, 1994, I appeared on Phil Donahue’s live national television show to debunk the Holocaust deniers.26 The producers went to great lengths to keep me separated from them—different limos to the studio, different dressing rooms, different green rooms, different entrances to the set, and no talking during commercial breaks. Why? Because, I was told, they wanted the fresh drama of an initial encounter.) In the evolution wars and sociobiology debates, Gould and Lewontin had a scientific agenda that they wanted to air publicly—that adaptationist, gene-centered arguments in evolutionary theory can be carried too far, and that much in the history of life can be explained by nonadaptive processes and a multileveled analysis of genes, individuals, and groups. What better way to do it than to use Wilson as their foil? But who in the general public knows or cares about adaptations, exaptations, spandrels, contingencies, and other esoterica of evolutionary biology? What the public does understand quite well are Nazis, eugenics, race-purification programs, and other abuses of biology of the past century. Thus, sociobiology’s critics reasoned, the best strategy is to begin with its ideological implications—particularly the racist overtones of genetic determinism—to capture an audience, then segue into the scientific arguments about the problems with hyperadaptationism. Gould said as much at a 1984 Harvard meeting Segerstråle attended: “We opened up the debate by taking a strong position. We took a definitive stand in order to open up the debate to scientific criticism. Until there is some legitimacy for expressing contrary opinions, scientists will shut up.” From this (and numerous interviews with all parties involved), Segerstråle concludes: “What I take Gould to be saying here is that the controversy around Wilson’s Sociobiology was, in fact, a vehicle for the real scientific controversy about adaptation! Far, then, from ‘dragging politics into it,’ or being ‘dishonest’ as [Ernst] Mayr accused Gould and Lewontin of being, their political involvement would have been instead a deliberate maneuver to gain a later hearing for their fundamentally scientific argument about adaptation. What Gould seems to have been saying here is that the scientific controversy about adaptation could not have been started without the political controversy about sociobiology.”27
Before we accuse Gould and Lewontin of being overly Machiavellian in their political machinations, however, we should note that Wilson was not an innocent victim in this debate. It seems unlikely that a Harvard professor could author a book whose title defines a new science of applying biology to human social and moral behavior, in the middle of a decade that was defined by its ideological emphasis on egalitarian politics and cultural determinism, and not expect trouble. In point of fact, of course, all scientists have an agenda and the sooner we recognize that fact and come clean with our own, the better able the public will be to judge scientific theories. Certainly Gould and Lewontin went too far, as all social movements are wont to do. When I first met Ed Wilson, I was surprised at what a kind, generous, and soft-spoken man he is—anything but what I had expected from following the sociobiology debates. Then again, it would appear that Wilson knew exactly what he was doing all along. Throughout his long and illustrious career Wilson has brilliantly orchestrated a scientistic program of biologizing all of human behavior, from mate selection and maternal love to mass genocide and morality. No wonder the evolution wars have been so heated. As he has always done with such aplomb over the decades and through numerous scientific battles, Ed Wilson let his pen do the talking. He responded to his critics with a Pulitzer Prize-winning answer in book form, On Human Nature, in which he succinctly threw down the gauntlet:
Above all, for our own physical well-being if nothing else, ethical philosophy must not be left in the hands of the merely wise. Although human progress can be achieved by intuition and force of will, only hard-won empirical knowledge of our biological nature will allow us to make optimum choices among the competing criteria of progress.28
Victory
Ed Wilson’s gauntlet was taken up by a cadre of scientists, philosophers, and scholars of many stripes, including anthropologist Donald Symons, psychologist Robert Axelrod, evolutionary biologist Robert Trivers, philosopher Michael Ruse, historian of science Robert Richards, biologist Richard Alexander, evolutionary theorist John Maynard Smith, sociologist James Q. Wilson, evolutionary biologist William D. Hamilton, primatologist Frans de Waal, and many others. Richard Dawkins’s 1976 The Selfish Gene was especially influential in getting people to think about applying science and evolution to human behavior, including moral behavior. To the concept of genes as carriers of information, Dawkins added “memes”—cultural carriers of information that go beyond biology yet act much like genes in terms of propagation, selection, and mutation. He even treated religious ideas as virus memes that, like computer viruses, invade our mental software, destroying our programs for rational thought and behavior. One of the best books making the case for the evolutionary origins of moral behavior is Matt Ridley’s 1997 The Origins of Virtue: Human Instincts and the Evolution of Cooperation. Robert Wright’s 1994 The Moral Animal is an engaging history of evolutionary ethics; Paul Farber’s 1994 The Temptations of Evolutionary Ethics is a scholarly history and critique; Philip Kitcher’s 1995 Vaulting Ambition provides a strong critique; and Paul Thompson’s 1995 Issues in Evolutionary Ethics is a useful collection of the most important works in the field, pro and con. At Skeptic magazine we devoted back-to-back special issues—with pro and con debates—on both evolutionary psychology and evolutionary ethics.29
As a final statement of victory, of sorts, in 1998 Ed Wilson published Consilience: The Unity of Knowledge, a magisterial sweep of the history of knowledge from the Enlightenment to the present. Wilson devoted a full chapter to ethics, as discussed in chapter 1, updating his argument from two decades prior (in Sociobiology and On Human Nature) by reducing the debate about the origins of the moral sense to an either-or choice between transcendentalists and empiricists. Wilson, of course, is an empiricist for whom God is an unnecessary hypothesis. “In simplest terms, the options are as follows: I believe in the independence of moral values, whether from God or not, and I believe that moral values come from human beings alone, whether or not God exists.” For Wilson, even Enlightenment atheist philosophers are still transcendentalists because “they tend to view natural law as a set of principles so powerful, whatever their origin, as to be self-evident to any rational person. In short, transcendental views are fundamentally the same whether God is invoked or not.” For the empiricist, at least in a Wilsonian sense, “if we explore the biological roots of moral behavior, and explain their material origins and biases, we should be able to fashion a wise and enduring ethical consensus.”30 Wilson began his analysis by admonishing ethicists for not opening their arguments with a caveat such as: “this is my starting point, and it could be wrong.” To his eternal (pardon the religious hyperbole) credit, Wilson had the intellectual integrity to end his own treatise on the material origins of ethics with this comment: “And yes—lest I forget—I may be wrong.”31
Today, evolutionary psychology, and its subfield of evolutionary ethics, are budding sciences ripe with both testable hypotheses and not so testable just-so stories. The debate has proven to be a lively one, and its critics have many important points to make, with plenty of cautions and caveats to go around about inappropriately applying evolutionary theory to human thought and behavior, but in my opinion the theory of evolution has won the day in both psychology and ethics. The field moved into its fourth phase in the early 1990s when sociobiology—under a new covering cloth of evolutionary psychology—gained general acceptance among a sizable group of evolutionary biologists and theorists. But it is only fair that I acknowledge that not everyone will agree with me that the application of evolutionary theory to human psychology and morality achieved victory at any time. Critics of evolution in general, and evolutionary biologists skeptical of evolutionary psychology in particular, may take issue with me on this point.
Consolidation
The fifth phase in the history of evolutionary ethics involves a consolidation of many evolutionary concepts, most notably a pluralistic and hierarchical model of evolution that recognizes causal elements other than natural selection—such as group selection—that have operated in human evolution. As in my caveat above, however, there are those who would argue that the consolidation took place in the victory stage and that group selection and hierarchical theory are nothing more than a minor wrinkle in the overall fabric of life. Thus, what follows is as much prescriptive as it is descriptive.
GROUP SELECTION, HIERARCHICAL EVOLUTIONARY THEORY, AND THE EVOLUTION OF MORALITY
As discussed in chapter 2, group selection has been a controversial subject and remains a topic of hot debate among evolutionary theorists today. Evolutionary biologist David Sloan Wilson recounts the story of how group selection became anathema:
George C. Williams is regarded as a hero by evolutionary biologists of the individualistic tradition. Specifically, he is the hero who severed the head of group selection and mounted it on a pole as an example of how not to think for future generations. As Williams tells the story (the last time I heard it was at the award ceremony for Sweden’s Crafoord Prize, which Williams received in 1999 along with John Maynard Smith and Ernst Mayr), he was a young postdoctoral associate at the University of Chicago and attended a lecture by Alfred Emerson, a highly respected biologist who portrayed all of nature as like a big termite colony. Williams knew that the evolution of higher-level adaptation was not so simple. As he listened to Emerson he thought “if this is evolution, I want to do something else—like car insurance.” Williams left the lecture muttering “Something must be done.” That something was Adaptation and Natural Selection, first published in 1966 and still widely read. Williams was one of many evolutionists who reacted against the superorganismic perspective but he became the icon for its rejection. I wish I could report otherwise, but scientists need their heroes and heads on poles as much as any other human group.32
Wilson replied to Williams and other group selection critics in his own works, including Unto Others: The Evolution and Psychology of Unselfish Behavior and Darwin’s Cathedral: Evolution, Religion, and the Nature
of Society.33 In addition to support from Darwin himself, who applied group selection in a limited fashion, Wilson has support from two other evolutionary theorists: Ernst Mayr and Stephen Jay Gould.
Ernst Mayr as Group Selectionist. Ernst Mayr is unquestionably the dean of twentieth-century evolutionary theory. Throughout his long career he has promulgated a limited form of group selection—limited to the human social group. In 1959 he credited J. B. S. Haldane as the first to identify (in 1932) the “population-as-a-whole as a unit of selection” (as group selection was then called), and suggests that the rate of mutation, degree of outbreeding, distance of dispersal, aberrant sex ratios, and other mechanisms favoring either in-breeding or out-breeding are attributes of populations (but not individuals) that would be selected for or against. In 1982 Mayr identified V. C. Wynne-Edwards as the scientist who formalized the group selection process, but still limited it to the deme, or population level, with only a brief mention of social groups. In 1988 Mayr agreed with the critics of group selection when it comes to animal groups, but argued, “there is a great deal of evidence that human cultural groups, as wholes, can serve as the target of selection. Rather severe selection among such cultural groups has been going on throughout hominid history.” In 1997 Mayr made a distinction between soft and hard group selection. Soft group selection “occurs whenever a particular group has more (or less) reproductive success than other groups simply because this success is due entirely to the mean selective value of the individuals of which the group is composed. Since every individual in sexually reproducing species belongs to a reproductive community, it follows that every case of individual selection is also a case of soft group selection, and nothing is gained by preferring the term soft group selection to the clearer traditional term individual selection.” Soft group selection is just individual selection writ large. Hard group selection, by contrast, “occurs when the group as a whole has certain adaptive group characteristics that are not the simple sum of the fitness contributions of the individual members. The selective advantage of such a group is greater than the arithmetic mean of the selective values of the individual members. Such hard group selection occurs only when there is social facilitation among the members of the group or, in the case of the human species, the group has a culture which adds or detracts from the mean fitness value of the members of the cultural group.” This is genuine group selection that differs qualitatively (not just quantitatively, as in soft group selection) from individual organismic selection, and is the subject of so much controversy. 34
Finally, in 2000, in an extensive interview of Mayr for Skeptic magazine, Frank Sulloway and I queried him on group selection and the controversy it has generated. He surprised us when he said: “George Williams and Richard Dawkins have made a mistake, in my opinion, in completely rejecting group selection. But we have to be careful here to define what we mean by a group. There are different kinds of groups. There is one type of group that is a target of selection, and that is the social group. Hominid groups of hunter-gatherers were constantly competing with other hominid groups; some were superior and succeeded and others were not. It becomes quite clear that those groups who had highly cooperative and altruistic individuals were more successful than the ones torn apart by internal strife and egotism.” So the social environment is as important as the physical environment. “The essential point is that if you are altruistic and make your group more successful, you thereby also increase the fitness of the altruistic individual (yourself)!” Critics, we noted, would argue that it is still the individual being selected for these characteristics, not the group. Mayr countered: “There is no question that the groups that were most successful had these individuals that were cooperative and altruistic, and those traits are genetic. But the group itself was the unit that was selected.”35
Stephen Jay Gould as Group Selectionist. Just before his untimely death in May 2002, Stephen Jay Gould witnessed the publication of his magnum opus, The Structure of Evolutionary Theory, in which he defended group selection as a legitimate part of a hierarchical theory of selection that recognizes different levels at which the selection process occurs.36 Gould begins by systematically building upon Darwin’s cathedral, an apt metaphor as his tome begins with an architectural analysis of the Duomo (Cathedral) of Milan, showing how the original fourteenth-century foundational structure was appended over the centuries with spires and pinnacles, such that we can legitimately say a core structure remains intact while the finished building represents a far richer compendium of historical additions. Gould’s mission is not to raze the Darwinian Gothic structure, or to tear down the neo-Darwinian Baroque facades, but to revise, refine, reinforce, and reconstruct those portions of Darwin’s Duomo that have begun to crumble under the weathering effects of a century and a half of scientific research. The foundation of Darwin’s Duomo rests upon three theoretical pillars that form the basis of a hierarchical theory of evolution: agency, efficacy, and scope.
Agency, or the level at which evolutionary change occurs. For Darwin, it is primarily individual organisms that are being selected for or against. Gould proposes a multitiered theory of evolution where change (and selection) occurs on six levels: gene, cell lineage, organism, deme, species, and clade. It is here where Gould defends his own version of group selection—which he calls species selection—without denying the power of Darwinian organismal selection. He does so with two caveats: “First, adjacent levels may interact in the full range of conceivable ways—in synergy, orthogonally, or in opposition. Second, the levels operate non-fractally, with fascinating and distinguishing differences in mode of functioning, and relative importance of components for each level. For example, the different mechanisms by which organisms and species maintain their equally strong individuality dictate that selection should dominate at the organismal level, while selection, drift, and drive should all play important and balanced roles at the species level.”37
Efficacy, or the mechanism of evolutionary change. For Darwin it was natural selection (and its handmaiden, sexual selection, where females, for example, select for or against characteristics that they like or dislike by choosing certain males) that drives organisms to evolve. Gould does not deny the power of natural selection, but wishes to emphasize that in the three-billion-year history of the earth’s rich panoply of life, there is more to the story. On top of the substratum of microevolution (short-term small changes) Gould adds macroevolution—long-term big changes caused by mass extinctions and other large-scale forces of change. To the bottom floor of adaptationism Gould attaches exaptationism—structures subsumed for later uses and whose original adaptive purposes are now lost to history.
Scope, or the range of effects wrought by natural selection. For Darwin, gradual and systematic change extrapolated over geological expanses of time is all that is needed to account for life’s diversity. For Gould, slow and steady sometimes wins the race, but life is also punctuated with catastrophic contingencies that fall in the realm of unique historical narratives rather than predictable natural laws. In Gould’s view, history, not physics, should be evolutionary theory’s model of science.
Revisions to these three branches of agency, efficacy, and scope (while the main Darwinian trunk retains its theoretical power), says Gould, produce a “distinct theoretical architecture, offering renewed pride in Darwin’s vision and in the power of persistent critiques—a reconstitution and an improvement.”38 How can the paradigms of the original Darwinism, the neo-Darwinism of the synthesis, and Gouldian Darwinism coexist peacefully? We can ask the same question with regard to individual versus group selection, or organismal versus species selection as apparently competing paradigms. In science, doesn’t one paradigm displace another in a way that makes them incompatible? No. Paradigms can build upon one another and cohabit the same scientific niche. Just as the Newtonian paradigm has been reconstituted to include the paradigms of relativity and quantum mechanics, the overarching Darwinian paradigm has been improved by, for example, the subsidiary punctuated equilibrium paradigm, which constitutes an improved reading of the herky-jerky fossil record whose numerous gaps so embarrassed Darwin. (The gaps, say Gould and his cotheorist Niles Eldredge, represent data of a speciation process that happens so rapidly that few “transitional” fossils are left in the historical record.) Darwinian gradualism and individual selectionism can be supplemented with Gouldian punctuationism and group selectionism. How?
Think of species not as billiard balls being knocked about the table of nature willy-nilly, but as polyhedrons, or multifaceted structures (picture an eight-sided die) that sit on a side until nudged by a potent force, and whose internal properties, Gould writes, “‘push back’ against external selection, thereby rendering evolution as a dialectic of inside and outside.” Without discounting the outside, Gould wants us to look again inward (as so many evolutionary theorists did in Darwin’s own day), where the restricting channels of both nature and history direct the selective forces in particular directions. Although individual selection is more potent and common than group selection, the latter may outdo the former under certain conditions, as is the case with the selection for human morality. “Organismic selection may trump species selection in principle when both processes operate at maximal efficiency, but if change associated with speciation operates as ‘the only game in town,’ then a weak force prevails while a potentially stronger force lies dormant. Nuclear bombs certainly make conventional firearms look risible as instruments of war, but if we choose not to employ the nukes, then bullets can be devastatingly effective.”39
Ernst Mayr said we need to be precise in how we define a group. The same is true in defining what we mean by group selection, and how human morality may have evolved—at least in part—as a function of the group selection process. Darwin focused on tribes, and how they differed in terms of patriotism, fidelity, obedience, courage, and sympathy, and how these differences led to the selection of some tribes over others. Mayr talks about groups in terms of their social bonding and interactions, and how this might have led to certain groups being selected for survival over others. Gould’s emphasis on species selection would seem beyond the scope of these more narrowly confined cohorts, but if we think of the rapid extinction of Neanderthals shortly after the arrival of anatomically modern Cro-Magnon humans—considered to be separate species by most paleoanthropologists—this too may be an example of group selection, where the group is the entire species. And the consequences of an entire hominid species disappearing forever off the face of the earth are profound.