Reviewed by PIERRE L. VAN DEN BERGHE, Department of Sociology,
University of Washington, SEATTLE, WA 98195-3340, USA.
In 1973, Goldberg published The Inevitability of Patriarchy, one of a score or more
of initial salvos shot by social scientists at then-still-reigning extreme
environmentalism of the majority of their colleagues. Its style was cockily
argumentative but refreshingly revisionist of a dominant orthodoxy that was just
beginning to come unstuck. By 1993, the publication date of this book, the radical
environmentalist orthodoxy of the social sciences was in total shambles, but
Goldberg still feels compelled to kick open doors, and to slay dead horses.
Furthermore, Goldberg failed to understand the new dominant paradigm that
replaced it, evolutionary ecology or sociobiology. Consequently, this book is
tedious, repetitious, pedantic, and theoretically limited.
Basically, he repeats ad nauseam his thesis of the universality of "patriarchy," (an empirical generalization on which there is virtually unanimous agreement among anthropologists), and he suggests a proximate, ontogenic "explanation" for it namely that "male hormonalization... is primarily responsible for the greater male dominance tendency" (p. 82). In short, male hormones impel males more than females to compete for dominance, and this is what gives them an advantage over women in dominance contests. The sex difference is statistical, not absolute, and there are individual cases of politically dominant women, but, in the aggregate, there are no societies (nor have there ever been any) in which women, as a class, dominated men, or in which women have occupied more than a small minority of the top positions of power.
The empirical generalization of male dominance was already well supported in the 1973 book, and, in any case has seldom been challenged by anthropologists for the last thirty years. This book adds nothing to the factual basis of the thesis. Most of the 247 pages of text are devoted to tedious definitional exercises; lengthy refutations of past critics, feminist theorists, and others whose ideas belong to the curiosity cabinet of old-style environmentalist orthodoxy; pedantic methodological asides; and largely unrelated disquisitions on male-female differences in "cognitive aptitudes" and "high genius in the arts and sciences."
My criticisms, however, extend beyond the tedium, redundancy and irrelevance of much of this book, which is an overblown 20-page article, and not a very novel one at that. First, the authors central concept of "patriarchy" is a misnomer. Patriarchy means the authority of a father over his dependents of both sexes. What Goldberg means is the dominance of men over women, irrespective of kinship or marital status. This should be called andrarchy. To be sure, Goldberg is not responsible for the misnomer; he merely accepted a common but misleading usage of the term. However, for someone as pedant about definitions as he is, and as self-consciously assertive of this claim to present a revisionist perspective, a neologism would have been a small price to pay to eliminate a misleading misnomer. A more fundamental criticism is the proximate, ontogenic and extremely limiting nature of Goldbergs explanation of male dominance as the product of hormones, and his failure to understand the phenomenon in the broad, ultimate causation framework of evolutionary ecology. This failure is not accidental but deliberate. In several places, Goldberg explicitly rejects or refuses to address the evolutionary paradigm that he characterizes as interesting but speculative, largely, I suspect, because he is not well enough read in it to understand it. (See especially pp. 77-80, 125-126, and 166-167, when he dismisses the sociobiological approach, and refuses to consider sexual dimorphism in size, mating systems, and sex asymmetries in parental investment and mate selection strategies as explanations for sex differences in dominance behavior.) In short, Goldberg simply ignores the dominant paradigm explaining a multitude of sex differences in a vast range of sexually reproducing organisms in terms of a simple model of fitness maximization. Instead, he opts for a limiting, species- specific, proximate, hormonal explanation which dangles in a theoretical vacuum. This extraordinary display of intellectual myopia is all the more surprising when it comes from one who argues so forcibly for the relevance of biology to an understanding of human behavior. How is it possible for someone who is not hostile to biological explanations to ignore mating and reproductive systems in accounting for dominance and competition, both intra- and inter-sexual? Yet, Goldbergs book is almost entirely bereft of references to ethology, behavioral ecology, or sociobiology, even that which deals principally or exclusively with humans. Goldberg concedes (p. 223) that his approach puts the emphasis on male behavior, but fails to see that male behavior is incomprehensible except conjointly with female behavior, and that sexual dimorphism in size, behavior, physiology, and indeed, everything, is only understandable within the evolutionary paradigm of sexual selection, parental investment and fitness maximization. Instead, Goldberg lamely fixates on one proximate mechanism of sexual dimorphism, hormonal physiology, to explain one behavioral dimorphism, dominance drive.
If Goldberg wants to contribute to an understanding of the biological bases of human behavior, he would do better to familiarize himself with the central evolutionary paradigm than to puncture feminist windbags, beat the ghosts of Engels and Morgan, and excoriate his inconsequential critics.
by DONALD E. BROWN, Department of Anthropology, University of California,
Santa Barbara, CA 93106, U.S.A.
This weighty book, described in a Foreword by Gustav Jahoda as "a remarkably
comprehensive survey of the current state of the art and science of cross-cultural
psychology" (p. x), and written by prolific contributors to the field, is intended for
classes at an advanced level. Since the book appears to have been well received - the
review copy indicates that it is already in its fourth printing - I propose to offer a
critique that is as much of the field the book summarizes as it is of the book itself.
First, however, the book must be summarized.
In the introduction and elsewhere in the book the authors define the field and distinguish it from closely related fields - in terms of goals, methods, and objects or areas of study. Thus in cross-cultural psychology individual-level issues and experimental studies predominate (whereas in psychological anthropology population- level issues and naturalistic studies are more common). The approach of cross- cultural psychology is fundamentally social-scientific, so that the psychobiological bases of behavior and psychophysiological measurements - which are presumed to be much the same in all cultures - are not emphasized. Most of the cross-cultural research is conducted in modern societies, predominantly among the culturally distinct populations of the United States. Even when it goes beyond the United States, the authors state that much of the research is more correctly described as cross-national rather than cross-cultural. Major goals, according to the authors, are the discovery of psychological laws and a universal psychology, even though achieving the latter seems to the authors to lie well in the future. The authors repeatedly stress an emphasis on universals, and assert that "the field is moving toward the[ir] explication" (p. 187). The authors distinguish their universalistic approach - which takes both biology and culture into account - from that of psychological relativism - which stresses culture - and psychological absolutism - which stresses biology. They hold that "basic psychological processes are likely to be common features of human life everywhere, but that their manifestations are likely to be influenced by culture" (p. 258). With some ambivalence (noted below), they consider psychological universals to be likely sources of cultural universals. The authors attempt to avoid ethnocentrism and value judgments.
In a summary statement, the authors note that their "attention...[has been] guided by an ecocultural framework.... Central to this framework has been the view that individual human beings develop and exhibit behaviors that are adaptive to the ecological and sociopolitical contexts in which they and their group find themselves" (p. 391).
After the introduction, part one of the book discusses "similarities and differences in behavior across cultures" under five headings: "cultural transmission and development," "social behavior," "personality," "cognition," and "perception." The second part discusses research strategies under the headings "cultural approaches," "biological approaches," "methodological concerns," and "theoretical issues in cross-cultural psychology." Part three, devoted to the application of research findings, has six headings: "acculturation and culture contact," "ethnic groups and minorities," "organizations and work," "communication and training," "health behavior," and "psychology and the developing world." There is a brief epilogue.
Although extensive materials are covered - with the clarity and detail that is required for a classroom text - inevitably the authors have had to make crucial decisions about what to include and exclude, and what to emphasize. They comment frequently on the rationale that underlies their decisions. Some implicit features of the book should also be noted: Since it is fundamentally a review of the field, its emphasis is overwhelmingly on the (recent) past, with relatively little said about the directions that should be taken in the future. Furthermore, the book is heavily influenced by the practical concerns of modern, complex societies and is more method- than theory-driven.
The critique that follows focusses on theoretical or conceptual issues, primarily the relationships between culture, biology, psychology, and universals. Generally, the authors' position on these issues is bioculturally interactionist, but their position is not fully developed and not consistently maintained. I will also discuss certain aspects of the authors' treatment of plural societies.
A major problem, not confined to cross-cultural psychology but running throughout those fields that emphasize the culture concept, is how to distinguish the cultural from the noncultural. The various definitions of culture given in the book (e.g., pp. 1, 165f, 186) do not suffice, for example, to distinguish behaviors that emerge as a result of maturation from those that result from socialization into particular cultural traditions or to distinguish what might affect human behavior for fundamentally demographic or ecological reasons from fundamentally cultural effects. To illustrate the latter problem, it is highly likely that the presence of social hierarchy or of certain population densities affects human behavior because of our nature (i.e., regardless of cultural norms) and even that humans might be specifically adapted to modify their behavior in response to specific noncultural ecological conditions. The concept of "facultative adaptation" is the key idea here, and (like other key terms from evolutionary theory) it does not appear to be a part of the thinking that went into this book.
A closely related problem concerns the authors' treatment of universals. While it is never explicitly stated, their treatment of universals implies, first, that they are absolute or unconditional (i.e., found in much the same form in all cultures) and, second, that whatever is constant across cultures is likely to reflect human biology (while what varies is likely to be cultural). But an important form of universality is the conditional or implicational universal (Brown 1991). Like a facultative adaptation, a conditional universal is present or absent, or takes different forms, in accord with universally specifiable conditions. Once this kind of universal is taken into consideration, it is no longer tenable to assume that if something varies it must be due to culture.
In various contexts the authors also imply that universals are of classification, not content (i.e., general, like "religion", but not specific; see especially p. 170). This is a widespread conception in the social sciences, but is wrong. Elsewhere in the book the authors summarize the study of such highly specific universal behaviors as the facial expressions of emotions, which are universals of content.
In some contexts the authors indicate typical social-scientific ambivalence about the relationship between biology, on the one hand, and culture and psychology, on the other. Early on, they warn against reductionism: "we need to avoid reducing culture to the level of psychological explanations, of psychological phenomena to biological explanations" (p. 6). This is a hallowed feature of what Tooby and Cosmides (1992) refer to as the Standard Social Science Model (SSSM). But this anti-reductionist view cannot fully be squared with the idea that "cultural universals reflect psychological universals" (p. 170), unless one seriously confines the meaning of "reflect;" nor, I believe, can it really be squared with much that the authors say about psychological universals elsewhere in the book. Now if reductionism implied something like "explain entirely in terms of," there might be some justifiable reservations. But if anti-reductionism is understood to mean that biology can play no role in explaining psychology or that psychobiology can play no role in explaining culture, it is absurd. It is not even defensible to say that biology must play a small role, as there is no obvious way to quantify the matter.
Perhaps the most striking illustration of their anti-reductionist stance, and to some extent the authors' ambivalence toward it, is their treatment of sex differences, which they see as "best viewed as a product of socialization emphases" (p. 26) and "a cultural construction on a biological foundation" (p. 59).
Biologically males and females have different sex organs and sex hormones; there are also differences in average size and weight. However, on the basis of these, all the extant collective images, including values, cultural beliefs (stereotypes), and expectations (ideology) swing into action, leading to sex differences in child-rearing and role differentiation and assignment, and eventually to sex differences in a number of psychological characteristics (abilities, aggression, and so forth) (p. 59).
There is no indication here of the role that hormones play in shaping distinct male and female brains - for evolutionarily sound reasons - and the obvious inference that brain differences might underlie some of the psychological characteristics that distinguish male from female. After all, this is a reasonable explanation for some of the gender stereotypes that "show substantial universality" (p. 60).
Without claiming it as their own, the authors summarize this sort of explanation in their chapter on biological approaches: the widespread nature of a trait is the "criterion for a biological origin" (p. 213). Sex differences in sexuality have been the targets for a "particularly intensive" (p. 213) application of this idea, tracing these differences to the differing reproductive strategies that flow from the differing reproductive potentials of male and female.
In spite of their rigid cultural constructivist views on sex differences, the authors do summarize two important biological fields: sociobiology and ethology. The latter is well surveyed, but the summary of sociobiology omits an explicit discussion of evolutionary (or Darwinian) psychology, which could hardly be more germane to cross-cultural psychology. Given the authors' "position that psychological processes are shared species-wide characteristics" (p. 391), there is no theoretically defensible alternative to fully embracing the one theory that explains species characteristics and, especially, the branch of it that focusses on psychology. Perhaps the key indicator of the authors' neglect of evolutionary approaches is the absence of the term "mental organ" or "mental mechanism." This concept, the notion of "domain specificity," and such concerns as the distinction between "adaptive" and "adapted" are directly related to theoretical issues the authors highlighted (see Barkow, Cosmides, and Tooby  for a recent summary of evolutionary psychology). Curiously, the authors also express ambivalence as to whether their whole enterprise has promise as a science or is simply a projection of fundamentally ethnocentric concerns. Thus the authors summarize the accusation that cross-cultural psychology is inherently ethnocentric and a spinoff of social Darwinism. And they assess the study of ethnopsychologies - i.e., the folk- or indigenous psychologies of other peoples - as a possible corrective to ethnocentrism. Their assessment is not particularly encouraging, for the good reason that "only a few indigenous theories... lend themselves to a critical analysis of their validity" (p. 383). Accordingly, they concede too much, or speak too loosely, when they say, "Of course, Western psychology is one such indigenous psychology" (p. 381). While Western psychology has roots in a folk psychology, and may still be influenced by ethnocentric conceptions, its commitment to scientific skepticism and testing procedures takes it out of the realm of folk theory (otherwise, "heart" would still loom large in psychology). Its cross-cultural element, in particular, is a major tool for shedding psychology's ethnocentric conceptions.
The authors' discussion of plural societies raises a related problem. Their basic analytic framework is derived from modern Western societies, and focusses on minority-majority relationships. But if cross-cultural studies of plural societies are to develop theoretically (and avoid the ethnocentrism decried elsewhere in the book), they should employ a framework that in its basic outlines is applicable anywhere, not just in particular plural societies. There is such a framework, and its key elements are relations of dominance (which may or may not be present), demographic ratios (if there is dominance, whether those on top are a minority or majority), the jural condition of ethnic sections (whether ethnicity is "constitutionally" recognized - de facto or de jure - as qualifying citizenship). The various combinations of these elements produce distinct forms of plural societies, within which there is reason to predict that psychology and behavior will vary significantly. For example, J. S. Furnivall, a key figure in the formulation of the plural society concept, identified the absence of a "common will" as one of its distinct features (see the essays by Smith in Kuper and Smith  for a thorough exposition of the plural society concept or Brown [1976:80-83] for a summary). This insight has not received the attention it deserves in cross-cultural psychology. Linking the macro-concept of the plural society with the micro-processes isolated in "social identity theory" or "minimal group" theory (both discussed by Berry et al.) would be a timely line of research.
Maintaining objectivity is a final problem. While the authors claim a theoretical basis (derived from anthropology) for their "preference" for multicultural societies (p. 297), it is a lapse from their professed stance of objectivity. A value-laden "should" peppers their discussion of the plural society (pp. 309, 310, 310, 314). Moreover, they cite the Canadian government for the opinion that assimilation works nowhere, without any indication that this is false. Assimilation is widely reported in the ethnographic literature, is often very thoroughgoing and rapid, and in some cases is massive in its scope (e.g., the assimilation by Han Chinese of very large numbers of other peoples over long periods of time). Even in the United States today the rapid assimilation of Jews and Japanese Americans are well-known instances.
The social sciences suffered throughout much of this century from a theoretical disarray occasioned by the rise of behaviorism in psychology and by strong forms of social or cultural determinism in sociology and anthropology. To Berry et al.'s credit, behaviorism figures nowhere in their book. Like most social scientists, however, they are not prepared to take the further step - recommended by George Peter Murdock (1972), one of this century's most important cross-cultural comparativists - of abandoning the supra-individual concepts of society and culture. In their final sentence, in fact, the authors hope they have convinced the reader of the importance of culture. But if the culture concept is to play a part in scientific research surely it needs careful definition. If a universal psychology is to be discovered, surely evolutionary theory should be a guide. Through considerations such as these, cross-cultural psychology might improve on a record that, as Berry et al. show, is already extensive, brilliant in places, and exceedingly important in making sense of human affairs.
Barkow, Jerome H., Leda Cosmides, and John Tooby, eds. 1992. The Adapted Mind: Evolutionary Psychology and the Generation of Culture. New York: Oxford University Press.
Brown, Donald E. 1974. Principles of Social Structure: Southeast Asia. London: Duckworth.
Brown, Donald E. 1991. Human Universals. Philadelphia: Temple University Press.
Murdock, George Peter 1972. Anthropology's Mythology. Proc. Royal Anthropological Institute of Great Britain and Ireland for 1971. Pp. 17-24.
Kuper, Leo and M. G. Smith, eds. 1969. Pluralism in Africa. Berkeley: University of California Press.
Tooby, John and Leda Cosmides 1992. The Psychological Foundations of Culture. In The Adapted Mind: Evolutionary Psychology and the Generation of Culture. Ed. by Jerome H. Barkow, Leda Cosmides, and John Tooby. New York: Oxford University Press. Pp. 19-136.
This review was published earlier in the Journal of Social and Evolutionary Systems, 1996, Vol. 19, #3. © JAI Press.
Reviewed by JOHAN M.G. VAN DER DENNEN, Center for Peace and Conflict
Studies, University of Groningen, Oude Kijk in't Jatstraat 5/9, 9712 EA Groningen,
In the late seventies I wrote several volumes on Theories of War Causation, neatly
classifying sociological, psychological, psychoanalytic, economic, ecological-
demographic, political, etc. theories about the basic 'causes' of war as these diverse
disciplines envisaged them. After this exercise in '(meta)theoretical taxonomy' there
was a substantial residue of all kinds of theories that not so much located or
identified causes of war, but that proclaimed the inevitability, or even the necessity
of war, either to prevent the 'horrors' of peace (such as decadence, effeminacy, and
general pusillanimity), or because war was considered the Motor of Progress (moral,
cultural, spiritual or otherwise), and ranging in formulation from the sad acceptance
of a divine dictate to a full-blown panegyric. This rather heterogeneous category of
authors is better known as the Apologists or Cheerleaders of War.
One school of these Apologists especially emphasized the necessity of struggle, violence and war for the ongoing biological evolution of human groups, ethnies, and cultures. This, I learned, was the so-called Social Darwinist school of thought. And this was my first encounter with this particular breed of evolutionists who tended to interpret Darwin's "struggle for life" to include all levels of biotic (and even abiotic) existence (and elevate it to a universal principle), and "survival of the fittest" in terms of the bloody elimination of the weak and the vulnerable. "Nature: red in tooth and claw"; who could deny this Tennysonian metaphor?
Paul Crook, professor of history at the University of Queensland, is one of the latest of a modest number of writers on Social Darwinism (or Not-So-Social- Spencerism) in relation to war, covering the time span roughly from 1880 to 1919, the hey-days of war apologetics. Other aspects commonly associated with Social Darwinism, such as the eugenics movement, socioeconomic laissez-faire politics, racialism, etc. have engendered a respectable body of literature, but they are excluded from this review which focuses on the role of war in human affairs as envisaged by the Motor-of-Progress theorists.
"Is it true, as the textbooks tell us, that Darwinism basically encouraged war and racist imperialism, that it generated violent images of 'man the fighting animal' - perceptions that paved the way for the holocaust of 1914-18?" the blurb text of the book asks rhetorically. Crook skilfully reconstructs the theories of war and human pugnacity of thinkers such as Charles Darwin, Herbert Spencer, Walter Bagehot, Alfred Wallace, Thomas Huxley, Karl Pearson, Benjamin Kidd, Peter Kropotkin, Jacques Novicow, William McDougall, William James, Peter Chalmers Mitchell, William Graham Sumner and a host of now-forgotten naturalists, lesser deities and minor savants of the time. The book can be summarized in one sentence: The vicissitudes of Homo Pugnax and the cult of violence.
Before going on, I would like to remind the reader that the apology of war is not an invention of Social Darwinism; on the contrary, the entire history of European civilization has been characterized by more or less overt war-apologetic sentiments and doctrines (ranging in time from the Classical Greeks up to the present moment and ranging in content from metaphysical-religious to political-étatistic), sometimes blossoming into a veritable glorification and deification of war (de Maistre, Proudhon, Hegel, Gobineau, Gumplowicz, Nietzsche, von Treitschke, von Moltke, among many others). What the Social Darwinists added to the gamut of arguments was the notion of inevitable, orthogenetic, progress (a notion mainly stemming from Spencer, not Darwin) through struggle (interpreted as ferocious fighting).
In his Social Statics (1851) Spencer preached the inexorable progress in the course of history from a violent and chaotic early human state to higher stages that led ultimately to civilization and peace. War, bloodshed, enmity and cruelty - these 'manifold evils' were endemic and inevitable in early history, mandated by predatory instincts. The forces that were working out the ultimate 'great scheme of perfect happiness' took no account of incidental suffering, and exterminated "such sections of mankind as stand in their way, with the same sternness as they exterminate beasts of prey and herds of useless ruminants. Be he human being, or be he brute, the hindrance must be got rid of. Just as the savage has taken the place of lower creatures, so must he, if he have remained too long a savage, give place to his superior" (pp. 454-5). With a few exceptions, most primitives were unsociable and warlike. They were in the early 'egoistic' stage. However, the general direction of social evolution, according to Spencer, was from egoism to altruism. War and population pressure were the triggering mechanisms that - despite their antisocial character - helped impel humanity forward into higher civilization. Challenges like war and crowding fostered among conquering races qualities of social cohesion, mutual aid, inventiveness in artifacts and weapons, economic specialization and human differentiation: "From the very beginning the conquest of one people over another has been, in the main, the conquest of social man over antisocial man" (p. 455).
War, thus, had played a vital role in emancipating humans from an unruly, savage state. War had brought social cohesion during the militant stage of social evolution, the basis for emerging nation states and empires. In the contemporary industrial society, however, war and militarism, Spencer asserted, had become retrogressive and dysgenic. Struggle and violent competition ('pugnacity' or 'fighting instinct' were the contemporary terms), bloodshed and cruelty were generally regarded by the Social Darwinists as the crude filtering mechanisms by which species evolved and natural progress occurred. It was this 'nasty' aspect of natural selection that allegedly struck the 19th century imagination, the emphasis on differential mortality and the idea of the 'law of the jungle' as the harsh ruling principle governing not only animals in their habitats but also humans in their societies. It also provided ample justification for rampant capitalism and unbridled individualism/egoism, doctrines praising the 'fit' survivors (i.e. the wealthy) and damning the 'unfit', the losers, the poor, the human flotsam and jetsam, the Untermenschen. The rabidly racist and eugenic doctrines, as well as the notions of Blut und Boden, Lebensraum, and frische, fröhliche Krieg of Nazi Germany found their origins here.
Thomas H. Huxley (epithet "Darwin's bulldog") characterized these doctrines as the 'gladiatorial' theory of existence, embodying an ethic of 'reasoned savagery', as the weak were perpetually eliminated by the strong, or the most ruthless, or the most 'aggressive' individuals, groups, nations, etc. Huxley rejected the Noble Savage myth, and he preached a survivalist ethics. The "weakest and stupidest went to the wall". The toughest, shrewdest, and most adaptable survived. Popularisers (à la Ardrey in the 1960s) from the 1880s on wrote about man as 'killer ape', possessing an ineradicable 'instinct of pugnacity', implying that if violence is a constant human potential, war is not an aberrant activity, but, on the contrary, a biological necessity. The Dutch apologist Steinmetz, combining Hegelian tortuosity and Social Darwinist callousness, was the most 'sincere' and consequential: If war, he stated, is a (biological, moral, cultural, spiritual) necessity, an act of God in which He weighs the vigour of nations in His scales, abolition of war would be deeply immoral.
The Platonic imagery of the Beast Within - the source of ignobility, the incarnation of rampant carnal lust and destructiveness - intensified in the later 19th century and converged with instinct-psychology formulations of man's innate ineradicable violent urges. In 1870, anticipating MacLean's triune brain and Bailey's phylogenetic regression theory, Henry Maudsley (Body and Mind) claimed that there was a brute's brain within man's modern brain, as revealed by morbid psychology and the 'degeneration of insanity'.
Darwin, on the one hand, recognized that endemic warfare among 'savages' and genetic usurpation had been important selective forces in human history, but, on the other hand, he did not talk in terms of instinctive pugnacity in humans and, in agreement with Spencer, he warned that modern warfare was utterly dysgenic by wasting the 'best blood' of the nation on the battlefield.
He believed that through (violent) conflict - first among 'rude tribes', then nations and empires - had come, and would come, higher ethics and broader sympathy, which would ultimately render war obsolete.
Most militaristically-inclined thinkers, however, conveniently forgot or ignored these sobering ideas and depicted war and battle as Stahlbad der Seele, in which a true man could prove his virility, vigour, valour and dignity.
Bagehot was responsible for the notion that, at the first stage of the struggle for life, the most obedient and 'tamest' tribes were the strongest, and that "Civilisation begins, because the beginning of civilisation is a military advantage". Wars also encouraged innovation and variability. Darwin noted Bagehot's argument that warfare could result in racial mixtures that begat 'beneficial variability'. Hereditarian discourses flourished in the late nineteenth century. There was evoked a fatalistic language of innate human criminality, bellicosity and atavism. There was widespread fin de siècle alarm about 'degeneration' (both morally and physically) in western culture. Among the prophets of biological doom and retrogression were W.M. Flinders Petrie, F.W. Headley and Homer Lea who proclaimed that the continuance of competition is essential to the well-being of the civilized community. In his Valour of Ignorance (1909) Lea forecast 'gangrenous and fatal' results if humans thwarted the primal laws of struggle.
The remorseless slaughter of the unfit was simply Nature's drastic method of purifying and strengthening the human race. And wars were simply a test of a nation's fitness and social or moral virtue; an instrument of collective selection; a safeguard against moral decay, decadence and degeneracy. War was, in brief, a 'biological necessity'.
Ironically in the pre-1914 generation, as the world stood under the impending shadow of the First World War, thinkers were establishing beyond doubt the natural decline of warfare. While Jean de Bloch demonstrated that modern war was too costly and disruptive to be tolerated, and Norman Angell 'proved' that it was economically prohibitive, influential peace apostles such as Jacques Novicow, David Starr Jordan and Vernon Kellogg dismissed war as biologically destructive and outmoded. An age of fevered nationalisms and militaristic determinisms also brought forth 'peace eugenics', a discourse that brilliantly used the new genetics to reinforce mainstream peace Darwinism (associated with the name and ideas of Peter Kropotkin), and conducted a furious rhetorical offensive against the militarists. War was excoriated as dysgenic, an anachronism fated to disappear as human history moved into a higher phase of civilization.
Kropotkin, by the way, was not, as he is sometimes represented, an uncritical devotee of the Noble Savage myth. He avoided both extremes of the Rousseauian idealization of savages and the charging them with every bestial quality imaginable. He offered an early version of ethnocentrism theory (ingroup solidarity and outgroup hostility) to account for man's inhumanity to man.
In works such as La guerre et ses prétendus bienfaits (1894), translated into English as War and its Alleged Benefits (1912), and La critique du darwinisme social (1910), Novicow attacked supposedly Darwinian doctrines that considered 'collective homicide' as the mainspring of progress, and he exposed the economic, moral and biological waste of war. War, he maintained, has always caused negative selection: it was the fit and brave who had always gone off to fight and die on the battlefield, while it was the cowardly, sick and deformed who were left behind to propagate. Novicow's 'scientific pacifism' became virtually the orthodoxy of German and French peace movements in the pre-1914 years. Charles Richet, leading French physiologist and eugenist, dismissed war as an outmoded evolutionary factor in his Peace and War (1906) in which he openly attacked the whole idea of 'war instincts' and anticipated Margaret Mead's celebrated dictum that war was a human invention rather than a biological necessity.
Havelock Ellis, Thorstein Veblen, and G.F. Nicolai proposed that the warlike spirit was being selected out, as fighting stocks were naturally killed off in wars and the field left to the unwarlike.
The bestiality of World War I lent new intensity to the mythology of the Beast Within, which was now encoded anew in biological terms. Wartime literature was replete with metaphors about the fragility of civilization and the 'wild beast' lurking within humanity under the flimsy veneer of civilization. Freud merely systematized current opinion when he proposed in 1915 that culture was a fallible human construct whose function was to constrain violent and libidinal primal impulses.
George Crile, Harry Campbell and Carveth Read all anticipated Dart's and Ardrey's 'hunting hypothesis' by emphasizing how man, the hunting animal, hunted in packs which intensified human combativeness. In war they simply hunted each other.
After the First World War Peter Chalmers Mitchell's Evolution and the War (1915) constituted one of the more intelligent restatements of the 'optimist' tradition on the biology of war. Mitchell showed how people had misread Darwin's concept of struggle. Whereas Darwin used the concept of struggle in a large metaphorical sense, including dependence of organisms on one another, popularists gave it "the special significance of fierceness and cruelty".
The pre-1919 debate over 'the biology of war' may seem remote to us now. However, the resonances of that debate still echo in modern controversies. This is particularly so in the case of modern ethology and sociobiology. The founding fathers of these disciplines, most notably Konrad Lorenz and Edward O. Wilson, put neo-Darwinian interpretations of aggression based upon a speculative biohistory of humankind. So of course did a number of thinkers briefly dealt with here. One of Crook's two main theses in his brilliantly and eloquently written book is that
ethologists and sociobiologists seem to suffer from collective amnesia about their forebears. They have been remarkably reticent in acknowledging their intellectual ancestry, especially in the period before the great synthesising theories of Fisher, Sewall Wright and Haldane in the 1920s. When occasionally turning their hands to history, sociobiologists have given very garbled accounts of 'Social Darwinism' which they regard as an ideological taint to be avoided (p. 196).
Sociobiology, as everybody remembers, has been accused of about everything the accuser thinks abominable or abject, from sexism and racism to conservative politics and reactionary ethics. Crook's accusation of collective amnesia, however, deserves at least to be taken seriously.
The second main thesis of the book, namely that Darwinism bred an influential tradition of nonviolence, is hardly congruent with the familiar textbook scenario that Darwin's theory unleashed primarily harsh and divisive, conflict-based social doctrines. Yet, Crook is also convincing on this point.
As belated repentance for their sins this magnificent book should be read by all students of all bio-disciplines.
by JAMES H. FETZER, Department of Philosophy, University of Minnesota, 10
University Drive, Duluth, MN 55812-2496, U.S.A.
Marian Stamp Dawkins' book provides a fascinating and illuminating study of the
nature and existence of animal mind. Perhaps no other issue in animal ethology has
created as much controversy or generated as much disagreement as has this. With
the appearance of this work, however, most of that controversy should subside and
most of that disagreement disappear, where those who continue to deny the existence
of animal mind are now seen to support a cause that is lost.
Although Dawkins has written an immensely readable book that ought to have appeal far beyond the bounds of academia, she has also produced an important synthesis of recent research on this problem that deserves to be taken seriously by everyone with an interest in cognition. While she mentions two specific groups as her intended audience - namely, those who reject the existence of any but human mentality and those who accept the existence of animal mentality as obvious - her potential audience encompasses most philosophers, psychologists, biologists, and ethologists, in general.
Dawkins appears to appreciate what unreflective thinkers tend to overlook - namely, that without committing ourselves to some account of mind, we do not know what we are accepting or rejecting when we take a stand on either side. If we reject the existence of non-human kinds of mentality, for example, yet accept the existence of human mentality, what are we denying to other forms of life that we are ascribing to ourselves? Surely the first lesson of a scientific education is that we must understand the meaning of a hypothesis before we can subject it to test and accept or reject it.
The apparent hazard of any alternative approach is that literally we do not know what we are talking about. It can happen, however, that we, at least initially, only vaguely and incompletely understand the phenomenon that interests us, which arises when dealing with consciousness. Dawkins thus surveys (what she takes to be) varieties of consciousness that range from sensation and perception to recollection and abstract thinking, but confines herself (for the time being) to the conception of "consciousness" as immediate awareness, avoiding premature definitional commitments.
As Dawkins observes, the existence of consciousness even has ramifications for morality. If things that are conscious are things that deserve to be treated with respect, for example, then if non-human animals are also things that are conscious, then they deserve to be treated with respect. If non-human animals are not conscious, however, "then possibly we can get on with our meals and eradicate pests and do all sorts of things to them without being disturbed by the moral issues that might trouble us if we thought they were" (p. 6). So the question seems to possess a moral dimension.
Even more strikingly, however, consciousness also poses a problem of explanation from the perspective of evolution. Since it exists, it must be either an adaptation, which has provided adaptive benefits in the past, or an exaptation, whose presence has to be accounted for on non-adaptive grounds. Virtually every adaptive benefit that consciousness can be supposed to confer, such as learning to avoid bodily damage, however, might instead have been secured by non-conscious organisms or even by programmed machines. The rationale for its existence is therefore obscure.
Dawkins acknowledges two properties of (even human) consciousness that appear to make it scientifically problematic. One is that it is an essentially private phenomenon: what goes on inside of your head is not something to which anyone else has access. The other is that it is therefore impossible for anyone to possess certain knowledge about conscious phenomena - at least, in the case of anyone other than myself! The first seems to be an ontic (or ontological) property of consciousness as a special kind of being, the second an epistemic (or epistemological) consequence thereof.
The ascription of these properties to consciousness has a history that dates at least from the work of Descartes, but longevity does not imply validity. The privacy of consciousness may preclude others from direct access but it does not prevent indirect access: we typically draw inferences about the mental and emotional states of others based upon our observations of their speech and bodily behavior. And the absence of certain knowledge is compatible with the presence of uncertain knowledge: scientific knowledge is characteristically inductive and uncertain.
The Cartesian paradigm, according to which beliefs must be certain to qualify as knowledge, could be sustained only if knowledge were limited to what can be deduced from premises that are syntactical or semantical truths, which would preclude the possibility of any empirical knowledge. Indeed, Descartes' position was even less defensible, because he interpreted "certainty" as indubitability, which is a subjective property that varies from person to person. The Cartesian paradigm, properly understood, is no more than a prejudice having no significance for scientific inquiries.
The Cartesian paradigm is often accompanied by methodological commitments to analogical reasoning as the only kind possible for acquiring knowledge of other minds. This association, however, appears to be unwarranted on several grounds. Analogical reasoning involves comparing two things or kinds of things, where because one possesses properties A, B, C, and D, for example, and the second possesses A, B, and C, the second is supposed to possess D as well. Since I am a human and I feel pain if I burn myself on a hot stove, I infer the same is true of other humans, etc.
When there are more differences than similarities or few but crucial differences or such inferences are taken to be conclusive, however, then analogical reasoning is fallacious. The similarities and differences which matter are supposed to be relevant, in the sense that they make a difference to the outcome. When comparisons are drawn between members of different species, there may be more relevant differences than similarities. Even when comparisons are drawn between members of the same species, there can still be crucial differences. Such reasoning is always uncertain.
Since analogical reasoning is always uncertain, while Cartesian knowledge is always certain, it cannot provide Cartesian knowledge. Fortunately, Dawkins commits herself to the common-sense position that, "despite the impossibility of never [sic] really knowing what other people experience, we all go about our daily business as though we were perfectly well able to do so" (p. 10). She thus severs the Cartesian knot by declining to define "knowledge" in terms of certainty, which makes her reliance upon the use of analogical reasoning consistent with her concept of knowledge. But her methodology may actually be even more sophisticated in practice.
Dawkins thus maintains that the fundamental difficulty in reasoning about other species is to ensure that there are sufficient relevant similarities to warrant analogical arguments. She also emphasizes that different species have different bodies and inhabit different environments, where:
To be truly open to the discovery of what conscious experiences in other animals might be like, we must be prepared to go beyond the narrow-minded, rather arrogant anthropomorphism that sees human conscious experiences as the only or even the ultimate way of experiencing the world and make ourselves open to the much more exciting prospect of discovering completely new realms of awareness. (p. 14)
Indeed, she displays a refreshing sensitivity to the idea that other animals have "a point of view" that must be appreciated to fully understand them.
Dawkins acknowledges the existence of an enormous barrier to understanding other species, which takes the form of language. Indeed, some thinkers have gone so far as to insist that language is essential to thought, where absence of language implies absence of mentality. Communication between humans and non-humans may be limited, in Dawkins' view, but is not therefore impossible. It would be a blunder to assume either that other animals cannot communicate with one another without language or that animal modes of communication must always parallel human modes.
As soon as Dawkins turns her attention to criteria that may be used as evidential indications of the presence of animal consciousness, it becomes apparent her conception of consciousness may be somewhat broader than mere "immediate awareness". Her first criterion of consciousness, which I shall label (CC-1), is complexity of behavior, where "the complexity of behavior and the ability to adapt to changed circumstances are some of the hallmarks of a conscious mind" (p. 20). As an example, she offers vervet monkeys, who have different alarm calls for different kinds of predators.
Dawkins also introduces research by Cheney and Seyfarth, who have studied the sound patterns that vervets make under different conditions. They have discovered that the monkeys use at least four types of grunts under different social conditions, two of which are made when encountering socially dominant and socially inferior conspecifics, respectively, and two of which are made when moving into an open area and when observing unfamiliar monkeys from other groups. When tape- recorded sounds of these kinds were played to unsuspecting monkeys in the wild, moreover, they displayed responses appropriate to those particular messages.
Dawkins also discusses findings concerning female ostriches, red deer stags, and female black grouses that suggest ingenious strategies for raising chicks, picking fights, and selecting mates, where animal behavior is strongly influenced by subtle cues that are more complex but also more reliable than simpler alternatives. Dawkins' second criterion of consciousness, (CC-2), is adapting behavior to variable conditions (p. 36). Here she offers "undeniable evidence of ability to learn", which is exhibited by the pecking order of flocks of hens, the song- identification of white-throated sparrows, and concealing-of-food behavior of marsh tits and chickadees.
Indeed, her discussion of marsh tits and chickadees, who tend to hide hundreds of food items in the course of a single day, displays a great deal of methodological sophistication. In order to establish that these creatures are actually remembering exactly where they stored these items of food, a variety of alternative explanations - which might explain their remarkable ability by means of other causal mechanisms - have to be eliminated. Work by Sherry, Shettleworth and Krebs, which Dawkins cites, has tested various alternatives by using artificial trees and controlling the conditions.
In order to accept the hypothesis (H1) that chickadees and marsh tits have phenomenal memories, it was necessary to eliminate possible alternatives, including (H2) that they locate hidden seeds on the basis of smell or other subtle cues and (H3) that they have simple rules or routines they use for hiding and recovering food. Insofar as chickadees and tit marshes do not search systematically and follow no apparent routines, their behavior undermines hypothesis (H3). And because they tend to search in just those locations where they have stored food even after that food has been removed from those locations, their behavior also defeats hypothesis (H2).
The methodology applied here goes beyond mere analogical reasoning. A set of alternative possible explanations - some of which may be inspired by analogies - is introduced and subject to systematic evaluation. Hypotheses that explain more of the available evidence are preferred over those that explain less. Those that are preferable when sufficient evidence has become available are acceptable as true. Hypotheses that are inconsistent with that evidence are rejected as false. Any hypothesis that is accepted might still be false, but is the most rational among the alternatives. This is known as inference to the best explanation (Fetzer and Almeder 1993).
Other students of cognitive ethology have employed this methodology without acknowledging it by that name. The most striking instance with which I am familiar is Ristau's study of the piping plover (Ristau 1991), a bird that apparently deliberately feigns injury to lead predators away from its young, where she systematically eliminates the alternatives that this behavior is explainable (H1) as a reflexive or a fixed action pattern response, (H2) as conflict behavior, (H3) as an approach/withdrawal tendency, (H4) as a pre-programmed sequence of behavior, or (H5) as a kind of learning, where only (H6) as purposive or intentional behavior remains.
Ristau's study, like those of Sherry, Shettleworth and Krebs, also illustrates that every relevant alternative explanation must be taken into consideration. Otherwise, the true explanation need not be a member of the set of possible alternatives. Thus, the discovery that some possible alternative explanation has been overlooked may necessitate reconsideration of the inferential situation as a manifestation of the tentative character of scientific knowledge. Most importantly, however, it displays how hypotheses that make reference to cognitive variables are capable of being subjected to tests involving controlled experiments and focused observations.
The third criterion of consciousness Dawkins introduces, (CC-3), is learning from others (p. 45). This conception goes beyond merely learning from experience for oneself to include benefitting from the experience of others. It thus raises the prospect of communication and cooperation for the benefit of the community as a manifestation of the transmission of information from one generation to another as a form of "culture" or "tradition". What may be most surprising is that the example that Dawkins discusses is rats, who exemplify mental abilities that exceed what our preconceptions imply.
Dawkins discusses clever experiments involving pairs of rats conducted by Galef, in which he would expose one member of the pair (the "demonstrator" rat) to food scented with cocoa or cinnamon. The second member of the pair (the "observer" rat) would notice if the demonstrator appeared to be healthy or not after having eaten and would associate the scent that it detected with the (un)palatability of the scented food. The presence of the smells thus functions as a useful indication of correlated causes (scented foods) and effects (healthy or not) where one rat could learn from another.
Even more elaborate studies suggest that information about potential dangers can be transmitted within whole colonies of rats. A colony was regularly fed food of two kinds, X and Y. Food of kind X was then treated with lithium chloride, which makes rats ill but does not kill them. As a result, the whole colony stopped eating food X and only consumed food Y, an effect that persisted through subsequent generations, even though food X was no longer being treated with lithium chloride and was just as palatable as food Y. The rats were thereby perpetuating a tradition (pp. 48-52).
Dawkins introduces two additional criteria of consciousness in the form of (CC-4) behavior involving choice and (CC-5) behavior involving cooperation (p. 53). An example of behavior involving choice is that of cock house sparrows, who must decide whether or not to swoop after food on the lawn when a cat may or may not be in the vicinity. Studies by Elgar found that sparrows would behave one way or another under various conditions and even seemed to be making calculations about their risks and benefits. The sparrows were confronting options, weighing alternatives, and then acting.
Dawkins also discusses Wilkinson's studies of vampire bats, who share their food with other vampire bats who have shared their food with them in the past. They would typically not share their food with others who had not cooperated with them in the past. These creatures thus display behavior involving what is known as reciprocal altruism, where they help each other when they are in need in the expectation of reciprocation on other occasions. Vampire bats rely on their knowledge of each other's past history to cooperate in ways that turn out to benefit the community (pp. 58-61).
Other parts of the book provide a systematic analysis and extension of claims like those made in the first third, with examples that range from a mathematical parrot (pp. 119-126) to deception by chimpanzees (pp. 135-138) and aggression in Siamese fighting fish (pp. 157-158). Inference to the best explanation is repeatedly employed to establish that conclusions are reasonable when consideration is given to the full range of alternative explanations and the available relevant evidence. Some fairly explicit appeals occur with Clever Hans effects (pp. 68-75), thoughtful as opposed to rule-following behavior (p. 98), and higher mental abilities (pp.126-127).
Dawkins provides convincing reasons to conclude that consciousness, properly understood, makes an important difference to the behavior of organisms that possess it, especially in coping with problems that are novel or unpredictable, where unconscious and routine responses may not provide adequate solutions to adaptive problems (pp. 170-171). This generates a difference that enhances the relative fitness of organisms possessing this property in contrast with organisms that do not, which supplies a plausible explanation for the existence and evolution of consciousness.
In appraising this exceptional book, at least three ingredients seem to have been enormously important in contributing to its remarkable success. The first is that Dawkins did not allow herself to become embroiled in premature disputes over the precise nature and definition of "consciousness". The second is that Dawkins rejected the Cartesian conception of knowledge as certainty and substantially advanced tentative scientific understanding. The third is that Dawkins' belief in analogical reasoning complemented rather than interfered with her practice of inference to the best explanation.
Other readers may observe as I have observed that many of the kinds of consciousness that Dawkins considers - including most of those satisfying (CC-1) through (CC-5) as well as others she discusses - go beyond mere "immediate awareness". We may even want to admit that some forms of consciousness exist that do not satisfy even that modest conception. If internal bodily processes, such as digestion and gestation, for example, can take place without having any "immediate awareness" of those internalized activities, then it might turn out to be important to distinguish between (what could be called) sentience from the stronger forms of consciousness she considers.
We may ultimately acknowledge a continuum of grades of consciousness from sentience to awareness on to awareness with the ability to convey the contents of awareness and self-awareness consistent with Dawkins' position. And there may be more adequate conceptions of mentality than to identify it with consciousness. But their benefits are ontic rather than epistemic. I happen to believe that minds are best defined as sign-using (or "semiotic") systems - an approach that applies to humans, other animals and machines, if such a thing is possible (Fetzer 1990, 1991) - but I also know there are no better methodologies for scientific inquiries than those Dawkins has employed.
Fetzer, James H. (1990), Artificial Intelligence: Its Scope and Limits. Dordrecht,
The Netherlands: Kluwer Academic Publishers.
Fetzer, James H. (1991), Philosophy and Cognitive Science. New York, NY: Paragon House Publishers. 2nd edition, 1996.
Fetzer, James H. and Robert Almeder (1993), Glossary of Epistemology/Philosophy of Science. New York, NY: Paragon House Publishers.
Ristau, Carolyn (1991), "Aspects of the Cognitive Ethology of an Injury-Feigning Bird, The Piping Plover". In: Carolyn Ristau, ed., Cognitive Ethology (Hillsdale, NJ: Lawrence Erlbaum Associates, 1991), pp. 91-126.
This review was published earlier in the Journal of Social and Evolutionary
Systems, 1996, Vol. 19, #2,
pp. 187-192. © JAI Press.
by ARTHUR R. JENSEN, School of Education, University of California,
Berkeley, CA 94720, U.S.A.
This well-written and highly readable little book explicates the most recent status of
fact and theory in what was once called the nature-nurture controversy. This picture,
which has predominated in the behavioral genetics literature for at least several years
now, is here well-organized and presented succinctly by one of the leading figures in
the recent developments of this field. Robert Plomin, now at the Institute of
Psychiatry in London, is perhaps the most prolific researcher in contemporary
behavioral genetics and one of the most innovative. He writes with clarity and
authority on the topics of this book, which have been the focus of his own
First, it must be understood that the quantitative-genetic analysis of behavioral traits concerns individual differences in a trait, not the development of the trait in a given individual. This has been a source of confusion in the popular media's presentation of the nature-nurture debate. From the beginning, among those who work in this field, it has been axiomatic that both heredity and environment are equally and totally important in the individual's development, as no organism can even exist without both nature and nurture, or heredity and environment. The legitimate scientific question at issue has always concerned the causal factors in individual differences in observable or measurable phenotypic traits and how these differences are affected by genetic and environmental influences. Phenotypic individual differences in a population are measured as the variance, or the mean squared deviations of individuals from the group mean. Quantitative genetics provides the methodology for partitioning the total phenotypic variance of a given trait into its genetic and environmental components, including their covariance (GE cov) and their interaction (G X E), or nonadditive contributions to the total variance.
Representing this problem in terms of "nature versus nurture" or as "nature or nurture" is of course sheer nonsense, and has always been so regarded, from Galton's day to the present. This is just one more of the many misrepresentations of the issue in the popular culture.
What, in fact, has evolved in this field, from Galton to the present, is a shift in causal formulations that might be characterized as moving from the conception of "nature and nurture" to that of "nurture via nature." It is this transition in theory and research on nature-nurture that is the subject of this book. Its title, Genetics and Experience, is most appropriate, because it emphasizes the individual's actively experiencing and selecting what the environment offers rather than being passively subject to environmental influences. Here the individual's environment is no longer viewed merely as a hand of cards dealt to the person, which the person then plays as best as possible given the person's particular genotypic propensities. Rather, the environment is viewed more like a big cafeteria from which individuals make diverse selections that are compatible with their differing genotypes. Plomin contrasts these two views as instructionist (in which environment limits and shapes the individual's development) and selectionist (in which the individual selects from the environment only that which is most compatible with his or her genotypic propensities). "The essence of the selectionist argument is that what looks like instruction from the environment may be selection from built-in options" (p. 18). In other words, the organism is not a passive recipient of its environment, but seeks out and shapes the environment to suit its genotypic nature. It is not that just any environmental factors may be powerfully influential for a given individual, it's that different individuals have selected specific aspects of the environmental cafeteria that are most influential for them. Hence environmental factors that influence behavioral development largely operate to make children in the same family different from one another.
Plomin points out one of the important discoveries of the last decade, namely that "Many measures of the environment widely used in the behavioral sciences as indices of the environment show a genetic contribution" (p. 4). Moreover, some of the measures widely used in the behavioral sciences as indices of the environment are found to have some degree of heritability, that is, they reflect individuals' genotypes as much as they reflect the individual's objective environmental circumstances. A parent's treatment of a child, for example, is influenced not just by the parent's characteristics, but by the child's own genotypic tendencies. These ideas, originally, suggested in 1953 by the eminent Oxford geneticist, Cyril D. Darlington, were more recently formalized by Plomin and others in terms of genotype-environment covariance (GE cov), which comprises much of what is usually considered simply as environmental variance but actually involves the genes as well. GE cov refers to the fact that genotypes and environments have correlated effects; environmental influences are not entirely random with respect to genotypic tendencies; both may work in the same direction. Theoretically, and in some cases empirically, GE cov is analyzable into three components, passive, reactive, and active. The passive aspect is that part of the GE cov that is not directly caused by the individual's own volition or behavior; it is most prominent in infancy and early childhood, when the individual has relatively little control over the physical and social environment. It results from whatever genetic similarity exists between the parents and the offspring, since they share half their genes. For example, musical parents may provide a more musical environment, quite independent of their child's own behavior; but their child is also more likely to have inherited genes for greater musical sensitivity than is possessed by the average child and is therefore is more overtly responsive to musical sounds. Then there is the reactive component of the GE cov, whereby others in the child's environment react to its genotypic propensities. To continue the musical example, the parents, or others, notice the child's unusual responsiveness to music and therefore provide more of what attracts the child's interest. Music lessons are provided, teachers are enthusiastic about the pupil's progress, and the child's proclivity is further cultivated. By early adolescence the individual's autonomy and social environment have greatly broadened and the third component of the GE cov, the active aspect, now comes into full play. With or without encouragement, the individual actively seeks musical experiences, practices an instrument spontaneously, associates with musically talented peers, joins an orchestra, goes to concerts, buys recordings, and reads about music and musicians. Doing all these things to create a highly musical environment appears to "come naturally" to the individual and may even occur despite parents' efforts to discourage such consuming interest. (Beethoven's father tried to impose a musical environment on all three of his sons; he succeeded only with one.) This is indeed the abstract biography of every musician.
The same principles can be observed in the development of individuals in every walk of life. Genotypic characteristics influence experience and thus are differentially amplified by the opportunities for experience afforded by the environmental cafeteria. Plomin explains the various analytic models available to behavioral geneticists for detecting the components of variance attributable to the passive, reactive, and active components of the GE covariance from studies of twins, siblings, and adoptions, and gives many examples of such studies.
Some of the empirically established findings in recent years have resulted in a rather surprising revision of our knowledge of the behavior-genetic analysis of certain well-researched traits, particularly individual differences in intelligence, or psychometric g, the general factor common to all types of cognitive performance that meet some objective standard of accuracy or proficiency. The IQ is a fair approximation to g, but also reflects other factors besides g, such as verbal, spatial, numerical, and memory. The g factor per se, which is identified by the factor analysis of a battery of diverse cognitive tests, is slightly more heritable than is IQ as measured by standard test batteries, such as the Wechsler Intelligence Scales. The total environmental variance (including GE cov) is typically analyzed into shared environment (environmental influences shared by children reared in the same family and differing between families) and nonshared environment (i.e., environmental influences that differ among children in the same family and are specific to each child). Both shared and nonshared environmental influences contribute to the total phenotypic variance, in addition to genetic factors. Whereas previously is was believed that, in intellectual development, shared environmental effects (or environmental differences between families) contributed the larger part of the environmental variance, more recent age-trend studies of genetically unrelated individuals reared together show that this is true only during early childhood. Between early childhood and maturity, the shared component of environmental variance diminishes from about 40% of the total phenotypic variance to virtually zero. Over the same period, the nonshared environmental (or individual differences within families) effects on IQ remain relatively constant at about 20% of the phenotypic variance. What increases markedly from infancy to adulthood is the genetic variance, or heritability. In other words, through individuals' genetically influenced selective experience of the environmental cafeteria, genotypic tendencies become increasingly expressed in phenotypic behavior. The most recent evidence from large studies of monozygotic twins reared apart is that the broad heritability of IQ reaches about 70% in early maturity and about 80% by late maturity. Similar trends are seen in the domains of personality and temperament, though to a somewhat lesser degree than for mental ability.
Plomin also points out that there are genetic factors that show up in some measures of the environment and that influence experience per se independently of any particular psychological traits, unless one can speak of some trait of general experience-seeking or sensitivity to the environment. Some individuals apparently are genetically more exposed and open to the effects of experience than are others, independently of other measurable psychological traits, such as the well-known ability and personality factors.
The main themes explicated by Plomin in terms of their methodologies and current empirical evidence can be summarized briefly in terms of seven hypotheses, only the last of which has not yet accrued empirical support but is currently under investigation: (1) Genetic differences among individuals contribute to measures of the environment. (2) The genetic contribution to measures of the environment is greater for measures of active experience. (3) The genetic contribution to measures of the environment is due in part to psychological traits. (4) Genetic differences among individuals contribute to differences in experience independent of psychological traits. (5) Genetic factors contribute to links between environmental measures and developmental outcomes. (6) Processes underlying genetic contributions to experience change during development. (7) Specific genes that affect experience will be identified. Plomin's book may leave some readers with the impression that all of the nongenetic variance in human traits is attributable to specifically identifiable causes and may therefore even be intentionally manipulable eventually. However, there appears to be a base level of unaccounted for nongenetic variance which is attributable to wholly random microenvironmental events. This microenvironmental variance was first recognized by R.A. Fisher as "random somatic effects of the environment." It was emphasized later by C.D. Darlington in terms of "biological noise" and unequal division of the cytoplasm in the earliest stages of the zygote's development and to which he attributed a large part of the observed physical and behavioral differences between monozygotic twins reared together.
Recent analyses indeed show that a large part of the variance within MZ twin pairs fits a model of random microenvironmental variation (Jensen, 1996). In any single case, it would be difficult, if not impossible, to identify (or to control) the specific microenvironmental influences responsible for the difference in a given characteristic between any set of MZ twins. The sample random nongenetic factors must also affect singletons in the same way. While the specific sources of random environmental effects are not identifiable in the individual case, there are many likely candidates, virtually all of a biological nature, such as mother-child incompatibilities due to immunoreactive factors during fetal development (e.g., the Rh factor), mother's health, age, parity, drugs, X-rays, childhood diseases, nutrition, and many other factors, each contributing a small random nongenetic effect to the phenotypic variance. General advances in obstetrics, immunology, health care, and nutrition are probably reducing this source of variance to some degree in the populations of industrialized countries.
Jensen, A.R. (1996). The puzzle of nongenetic variance. In R.J. Sternberg & E.L. Grigorenko (Eds.) Intelligence, heredity, and environment. Cambridge, Mass: Harvard University Press.
This review was published earlier in the Journal of Social and Evolutionary Systems, 1996, Vol. 19, #3. © JAI Press.