Edward O Wilson’s ‘Sociobiology: The New Synthesis’: A Book Much Read About, But Rarely Actually Read

Edward O Wilson, Sociobiology: The New Synthesis Cambridge: Belknap, Harvard 1975

Sociobiology – The Field That Dare Not Speak its Name? 

From its first publication in 1975, the reception accorded Edward O Wilson’s ‘Sociobiology: The New Synthesis’ has been divided. 

On the one hand, among biologists, especially those specialist in the fields of ethology, zoology and animal behaviour, the reception was almost universally laudatory. Indeed, my 25th Anniversary Edition even proudly proclaims on the cover that it was voted by officers and fellows of the Animal Behavior Society as the most important ever book on animal behaviour, supplanting even Darwin’s own seminal On The Expression of Emotions in Man and Animals

However, on the other side of the university campus, in social science departments, the reaction was very different. 

Indeed, the hostility that the book provoked was such that ‘sociobiology’ became almost a dirty word in the social sciences, and ultimately throughout the academy, to such an extent that ultimately the term fell into disuse (save as a term of abuse) and was replaced by largely synonymous euphemisms like behavioral ecology and evolutionary psychology.[1]

Sociobiology thus became, in academia, ‘the field that dare not speak its name’. 

Similarly, within the social sciences, even those researchers whose work carried on the sociobiological approach in all but name almost always played down the extent of their debt to Wilson himself. 

Thus, books on evolutionary psychology typically begin with disclaimers acknowledging that the sociobiology of Wilson was, of course, crude and simplistic, and that their own approach is, of course, infinitely more sophisticated. 

Indeed, reading some recent works on evolutionary psychology, one could be forgiven for thinking that evolutionary approaches to understanding human behaviour began around 1989 with the work of Tooby and Cosmides

Defining the Field 

What then does the word ‘sociobiology’ mean? 

Today, as I have mentioned, the term has largely fallen into disuse, save among certain social scientists who seem to employ it as a rather indiscriminate term of abuse for any theory of human behaviour that they perceive as placing too great a weight on hereditary or biological factors, including many areas of research only tangentially connected to with sociobiology as Wilson originally conceived of it (e.g. behavioral genetics).[2]

The term ‘sociobiology’ was not Wilson’s own coinage. It had occasionally been used by biologists before, albeit rarely. However, Wilson was responsible for popularizing – and perhaps, in the long-term, ultimately unpopularizing it too, since, as we have seen, the term has largely fallen into disuse.[3] 

Wilson himself defined ‘sociobiology’ as: 

The systematic study of the biological basis of all social behavior” (p4; p595). 

However, as the term was understood by other biologists, and indeed applied by Wilson himself, sociobiology came to be construed more narrowly. Thus, it was associated in particular with the question of why behaviours evolved and the evolutionary function they serve in promoting the reproductive success of the organism (i.e. just one of Tinbergen’s Four Questions). 

The hormonal, neuroscientific, or genetic causes of behaviours are just as much a part of “the biological basis of behavior” as are the ultimate evolutionary functions of behaviour. However, these lie outside of scope of sociobiology as the term was usually understood. 

Indeed, Wilson himself admitted as much, writing in ‘Sociobiology: The New Synthesis’ itself of how: 

Behavioral biology… is now emerging as two distinct disciplines centered on neurophysiology and… sociobiology” (p6). 

Yet, in another sense, Wilson’s definition of the field was also too narrow. 

Thus, behavioural ecologists have come to study all forms of behaviour, not just social behaviour.  

For example, optimal foraging theory is a major subfield within behavioural ecology (the successor field to sociobiology), but concerns feeding behaviour, which may be an entirely solitary, non-social activity. 

Indeed, even some aspects of an organism’s physiology (as distinct from behaviour) have come to be seen as within the purview of sociobiology (e.g. the evolution of the peacock’s tail). 

A Book Much Read About, But Rarely Actually Read 

Sociobiology: The New Synthesis’ was a massive tome, numbering almost 700 pages. 

As Wilson proudly proclaims in his glossary, it was: 

Written with the broadest possible audience in mind and most of it can be read with full understanding by any intelligent person whether or not he or she has had any formal training in science” (p577). 

Unfortunately, however, the sheer size of the work alone was probably enough to deter most such readers long before they reached p577 where these words appear. 

Indeed, I suspect the very size of the book was a factor in explaining the almost universally hostile reception that the book received among social scientists. 

In short, the book was so large that the vast majority of social scientists had neither the time nor the inclination to actually read it for themselves, especially since a cursory flick through its pages showed that the vast majority of them seemed to be concerned with the behaviour of species other than humans, and hence, as they saw it, of little relevance to their own work. 

Instead, therefore, their entire knowledge of the sociobiology was filtered through to them via the critiques of the approach authored by other social scientists, themselves mostly hostile to sociobiology, who presented a straw man caricature of what sociobiology actually represented. 

Indeed, the caricature of sociobiology presented by these authors is so distorted that, reading some of these critiques, one often gets the impression that included among those social scientists not bothering to read the book for themselves were most of the social scientists nevertheless taking it upon themselves to write critiques of it. 

Meanwhile, the fact that the field was so obviously misguided (as indeed it often was in the caricatured form presented in the critiques) gave most social scientists yet another reason not to bother wading through its 700 or so pages for themselves. 

As a result, among sociologists, psychologists, anthropologists, public intellectuals, and other such ‘professional damned fools’, as well as the wider the semi-educated, reading public, ‘Sociobiology: The New Synthesis’ became a book much read about – but rarely actually read (at least in full). 

As a consequence, as with other books falling into this category (e.g. the Bible and The Bell Curve) many myths have emerged regarding its contents which are quite contradicted on actually taking the time to read it for oneself. 

The Many Myths of Sociobiology 

Perhaps the foremost myth is that sociobiology was primarily a theory of human behaviour. In fact, as is revealed by even a cursory flick through the pages of Wilson’s book, sociobiology was, first and foremost, a theoretical approach to understanding animal behaviour. 

Indeed, Wilson’s decision to attempt to apply sociobiological theory to humans as well was, it seems, almost something of an afterthought, and necessitated by his desire to provide a comprehensive overview of the behaviour of all social animals, humans included. 
 
This is connected to the second myth – namely, that sociobiology was Wilson’s own theory. In fact, rather than a single theory, sociobiology is better viewed as a particular approach to a field of study, the field in question being animal behaviour. 
 
Moreover, far from being Wilson’s own theory, the major advances in the understanding of animal behaviour that gave rise to what came to be referred to as ‘sociobiology’ were made in the main by biologists other than Wilson himself.  
 
Thus, it was William Hamilton who first formulated inclusive fitness theory (which came to be known as the theory of kin selection); John Maynard Smith who first introduced economic models and game theory into behavioural biology; George C Williams who was responsible for displacing a crude group-selection in favour of a new focus on the gene itself as the principal unit of selection; while Robert Trivers was responsible for such theories such as reciprocal altruismparent-offspring conflict and differential parental investment theory
 
Instead, Wilson’s key role was to bring the various strands of the emerging field together, give it a name and, in the process, take far more than his fair share of the resulting flak. 
 
Thus, far from being a maverick theory of a single individual, what came to be known as ‘sociobiology’ was, if not based on accepted biological theory at the time of publication, then at least based on biological theory that came to be recognised as mainstream within a few years of its publication. 
 
Controversy attached almost exclusively to the application of these same principles to explain human behaviour. 

Applying Sociobiology to Humans 

In respect of Wilson’s application of sociobiological theory to humans, misconceptions again abound. 

For example, it is often asserted that Wilson only extended his theory to apply to human behaviour in his infamous final chapter, entitled, ‘Man: From Sociobiology to Sociology’. 

Actually, however, Wilson had discussed the possible application of sociobiological theory to humans several times in earlier chapters. 
 
Often, this was at the end of a chapter. For example, his chapter on “Roles and Castes” closes with a discussion of “Roles in Human Societies” (p312-3). Similarly, the final subsection of his chapter on “Aggression” is titled “Human Aggression” (p 254-5). 
 
Other times, however, humans get a mention in mid-chapter, as in Chapter Fifteen, which is titled ‘Sex and Society’, where Wilson discusses the association between adultery, cuckoldry and violent retribution in human societies, and rightly prophesizes that “the implications for the study of humans” of Trivers’ theory of differential parental investment “are potentially great” (p327). 
 
Another misconception is that, while he may not have founded the approach that came to be known as sociobiology, it was Wilson who courted controversy, and bore most of the flak, because he was the first biologist brave, foolish, ambitious, farsighted or naïve enough to attempt to apply sociobiological theory to humans. 
 
Actually, however, this is untrue. For example, a large part of Robert Trivers’ seminal paper on reciprocal altruism published in 1971 dealt with reciprocal altruism in humans and with what are presumably specifically human moral emotions, such as guilt, gratitude, friendship and moralistic anger (Trivers 1971). 
 
However, Trivers’ work was published in the Journal of Theoretical Biology and therefore presumably never came to the attention of any of the leftist social scientists largely responsible for the furore over sociobiology, who, being of the opinion that biological theory was wholly irrelevant to human behaviour, and hence to their own field, were unlikely to be regular readers of the journal in question. 

Yet this is perhaps unfortunate since Trivers, unlike the unfortunate Wilson, had impeccable left-wing credentials, which may have deflected some of the overtly politicized criticism (and pitchers of water) that later came Wilson’s way. 

Reductionism vs Holism

Among the most familiar charges levelled against Wilson by his opponents within the social sciences, and by contemporary opponents of sociobiology and evolutionary psychology, alongside the familiar and time-worn charges of ‘biological determinism’ and ‘genetic determinism’, is that sociobiology is inherently reductionist, something which is, they imply, very much a bad thing. 
 
It is therefore something of a surprise to find among the opening pages of ‘Sociobiology: The New Synthesis’, Wilson defending “holism”, as represented, in Wilson’s view, by the field of sociobiology itself, as against what he terms “the triumphant reductionism of molecular biology” (p7). 
 
This passage is particularly surprising for anyone who has read Wilson’s more recent work Consilience: The Unity of Knowledge, where he launches a trenchant, unapologetic and, in my view, wholly convincing defence of “reductionism” as representing, not only “the cutting edge of science… breaking down nature into its constituent components” but moreover “the primary and essential activity of science” and hence at the very heart of the scientific method (Consilience: p59). 

Thus, in a quotable aphorism, Wilson concludes: 

The love of complexity without reductionism makes art; the love of complexity with reductionism makes science” (Consilience: p59). 

Of course, whether ‘reductionism’ is a good or bad thing, as well as the extent to which sociobiology can be considered ‘reductionist’, ultimately depends on precisely how we define ‘reductionism’. Moreover, ‘reductionism’, how ever defined, is a surely matter of degree. 

Thus, philosopher Daniel Dennett, in his book Darwin’s Dangerous Idea, distinguishes what he calls “greedy reductionism”, which attempts to oversimplify the world (e.g. Skinnerian behaviourism, which seeks to explain all behaviours in terms of conditioning), from “good reductionism”, which attempts to understand it in all its complexity (i.e. good science).

On the other hand, ‘holistic’ is a word most often employed in defence of wholly unscientific approaches, such as so-called holistic medicine, and, for me, the word itself is almost always something of a red flag. 

Thus, the opponents of sociobiology, in using the term ‘reductionist’ as a criticism, are rejecting the whole notion of a scientific approach to understanding human behaviour. In its place, they offer only a vague, wishy-washy, untestable and frankly anti-scientific obscurantism, whereby any attempt to explain behaviour in terms of causes and effects is dismissed as reductionism and determinism

Yet explaining behaviour, whether the behaviour of organisms, atoms, molecules or chemical substances, in terms of causes and effects is the very essence, if not the very definition, of science. 

In other words, determinism (i.e. the belief that events are determined by causes) is not so much a finding of science as its basic underlying assumption.[4]

Yet Wilson’s own championing of “holism” in ‘Sociobiology: The New Synthesis’ can be made sense of in its historical context. 

In other words, just as Wilson’s defence of reductionism in ‘Concilience’ was a response to the so-called sociobiology debates of the 1970s and 80s in which the charge of ‘reductionism’ was wielded indiscriminately by the opponents of sociobiology, so Wilson’s defence of holism in ‘Sociobiology: The New Synthesis’ itself must be understood in the context, not of the controversy that this work itself provoked (which Wilson was, at the time, unable to foresee), but rather of a controversy preceded its publication. 

In particular, certain molecular biologists at Harvard, and perhaps elsewhere, led by the brilliant yet but abrasive molecular biologist James Watson, had come to the opinion that molecular biology was to be the only biology, and that traditional biology, fieldwork and experiments were positively passé. 

This controversy is rather less familiar to anyone outside of Harvard University’s biology department than the sociobiology debates, which not only enlisted many academics from outside of biology (e.g. psychologists, sociologists, anthropologists and even philosophers), but also spilled over into the popular media and even became politicized. 

However, within the ivory towers of Harvard University’s department of biology, this controversy seems to have been just as fiercely fought over.[5]

As is clear from ‘Sociobiology: The New Synthesis’, Wilson’s own envisaged “holism” was far from the wishy-washy obscurantism which one usually associates with those championing a ‘holistic approach’, and thoroughly scientific. 

Thus, in On Human Nature, Wislon’s follow-up book to ‘Sociobiology: The New Synthesis’, where he first concerned himself specifically to the application of sociobiological theory to humans, Wilson gives perhaps his most balanced description of the relative importance of reductionism and holism, and indeed of the nature of science, writing: 

Raw reduction is only half the scientific process… the remainder consist[ing] of the reconstruction of complexity by an expanding synthesis under the control if laws newly demonstrated by analysis… reveal[ing] the existence of novel emergent phenomena” (On Human Nature: p11). 

It is therefore in this sense, and in contrast to the reductionism of molecular biology, that Wilson saw sociobiology as ‘holistic’. 

Group Selection? 

One of the key theoretical breakthroughs that formed the basis for what came to be known as sociobiology was the discrediting of group-selectionism, largely thanks to the work of George C Williams, whose ideas were later popularized by Richard Dawkins in The Selfish Gene (which I have reviewed here).[6] 
 
A focus the individual, or even the gene, as the primary, or indeed the only, unit of selection, came to be viewed as an integral component of the sociobiological worldview. Indeed, it was once seriously debated on the pages of the newsletter of the European Sociobiological Society whether one could truly be both a ‘sociobiologist’ and a ‘group-selectionist’ (Price 1996). 

It is therefore something of a surprise to discover that the author of ‘Sociobiology: The New Synthesis’, responsible for christening the emerging field, was himself something of a group-selectionist. 

Wilson has recently ‘come out’ as a group-selectionist by co-authoring a paper concerning the evolution of eusociality in ants (Nowak et al 2010). However, reading ‘Sociobiology: The New Synthesis’ leads one to suspect that Wilson had been a closet, or indeed a semi-out, group-selectionist all along. 

Certainly, Wilson repeats the familiar arguments against group-selectionism popularised by Richard Dawkins in The Selfish Gene (which I have reviewed here), but first articulated by George C Williams in Adaptation and Natural Selection (see p106-7). 

However, although he offers no rebuttal to these arguments, this does not prevent Wilson from invoking, or at least proposing, group-selectionist explanations for behaviours elsewhere in the remainder of the book (e.g. p275). 

Moreover, Wilson concludes: 

Group selection and higher levels of organization, however intuitively implausible… are at least theoretically possible under a wide range of conditions” (p30). 

 
Thus, it is clear that, unlike, say, Richard Dawkins, Wilson did not view group-selectionism as a terminally discredited theory. 

Man: From Sociobiology to Sociology… and Perhaps Evolutionary Psychology 

What then of Wilson’s final chapter, entitled ‘Man – From Sociobiology to Sociology’? 

It was, of course, the only one to focus exclusively on humans, and, of course, the chapter that attracted by far the lion’s share of the outrage and controversy that soon ensued. 

Yet, reading it today, over forty years after it was first written, it is, I feel, rather disappointing. 

Let me be clear, I went in very much wanting to like it. 

After all, Wilson’s general approach was basically right. Humans, like all other organisms, have evolved through a process of natural selection. Therefore, their behaviour, no less than their physiology, or the physiology or behaviour of non-human organisms, must be understood in the light of this fact. 

Moreover, not only were almost all of the criticisms levelled at Wilson misguided, wrongheaded and unfair, but they often bordered upon persecution as well.

The most famous example of this leftist witch hunting was when, during a speech at the annual meeting of the American Association for the Advancement of Science, he was drenched him with a pitcher of water by leftist demonstrators. 

However, this was far from an isolated event. For example, an illustration from the book The Moral Animal shows a student placard advising protesters to “bring noisemakers” in order to deliberately disrupt one of Wilson’s speaking engagements (The Moral Animal: illustration p341). 

In short, Wilson seems to have been an early victim of what would today be called ‘deplatorming’ and ‘cancel culture’, phenomena that long predated the coining of these terms

Thus, one is tempted to see Wilson in the role of a kind of modern Galileo, being, like Galileo, persecuted for his scientific theories, which, like those of Galileo, turned out to be broadly correct. 

Moreover, Wilson’s views were, in some respects, analogous to those of Galileo. Both disputed prevailing orthodoxies in such a way as to challenge the view that humans were somehow unique or at the centre of things, Galileo by suggesting the earth was not at the centre of the solar system, and Wilson by showing that human behaviour was not all that different from that of other animals.[7]

Unfortunately, however, the actual substance of Wilson’s final chapter is rather dated.

Inevitably, any science book will be dated after forty years. However, while this is also true of the book as a whole, it seems especially true of this last chapter, which bears little resemblance to the contents of a modern textbook on evolutionary psychology

This is perhaps inevitable. While the application of sociobiological theory to understanding and explaining the behaviour other species was already well underway, the application of sociobiological theory to humans was, the pioneering work of Robert Trivers on reciprocal altruism notwithstanding, still very much in its infancy. 

Yet, while the substance of the chapter is dated, the general approach was spot on.

Indeed, even some of the advances claimed by evolutionary psychologists as their own were actually anticipated by Wilson. 

Thus, Wilson recognises:

One of the key questions [in human sociobiology] is to what extent the biogram represents an adaptation to modern cultural life and to what extent it is a phylogenetic vestige” (p458). 

He thus anticipates the key evolutionary psychological concept of the Environment of Evolutionary Adaptedness or EEA, whereby it is theorized that humans are evolutionarily adapted, not to the modern post-industrial societies in which so many of us today find ourselves, but rather to the ancestral environments in which our behaviours first evolved.

Wilson proposes examine human behavior from the disinterested perspective of “a zoologist from another planet”, and concludes: 

In this macroscopic view the humanities and social sciences shrink to specialized branches of biology” (p547). 

Thus, for Wilson: 

Sociology and the other social sciences, as well as the humanities, are the last branches of biology waiting to be included in the Modern Synthesis” (p4). 

Indeed, the idea that the behaviour of a single species is alone exempt from principles of general biology, to such an extent that it must be studied in entirely different university faculties by entirely different researchers, the vast majority with little or no knowledge of general biology, nor of the methods and theory of researchers studying the behaviour of all other organisms, reflects an indefensible anthropocentrism

However, despite the controversy these pronouncements provoked, Wilson was actually quite measured in his predictions and even urged caution, writing 

Whether the social sciences can be truly biologicized in this fashion remains to be seen” (p4) 

The evidence of the ensuing forty years suggests, in my view, that the social sciences can indeed be, and are well on the way to being, as Wilson puts it, ‘biologicized’. The only stumbling block has proven to be social scientists themselves, who have, in some cases, proven resistant. 

‘Vaunting Ambition’? 

Yet, despite these words of caution, the scale of Wilson’s intellectual ambition can hardly be exaggerated. 

First, he sought to synthesize the entire field of animal behavior under the rubric of sociobiology and in the process produce the ‘New Synthesis’ promised in the subtitle, by analogy with the Modern Synthesis of Darwinian evolution and Mendelian genetics that forms the basis for the entire field of modern biology. 

Then, in a final chapter, apparently as almost something of an afterthought, he decided to add human behaviour into his synthesis as well. 

This meant, not just providing a new foundation for a single subfield within biology (i.e. animal behaviour), but for several whole disciplines formerly virtually unconnected to biology – e.g. psychology, cultural anthropology, sociology, economics. 

Oh yeah… and moral philosophy and perhaps epistemology too. I forgot to mention that. 

From Sociobiology to… Philosophy?

Indeed, Wilson’s forays into philosophy proved even more controversial than those into social science. Though limited to a few paragraphs in his first and last chapter, they were among the most widely quoted, and critiqued, in the whole book. 

Not only were opponents of sociobiology (and philosophers) predictably indignant, but even those few researchers bravely taking up the sociobiological gauntlet, and even applying it to humans, remained mostly skeptical. 

In proposing to reconstruct moral philosophy on the basis of biology, Wilson was widely accused of committing what philosophers call the naturalistic fallacy or appeal to nature fallacy

This refers to the principle that, if a behaviour is natural, this does not necessarily make it right, any more than the fact that dying of tuberculosis is natural means that it is morally wrong to treat tuberculosis with such ‘unnatural’ interventions as vaccination or antibiotics. 

In general, evolutionary psychologists have generally been only too happy to reiterate the sacrosanct inviolability of the fact-value chasm, not least because it allowed them to investigate the evolutionary function of such morally dubious, or indeed morally reprehensible, behaviours as infidelity, rape, war, sexual infidelity and child abuse, while denying they are thereby providing a justification for the behaviours in question. 

Yet this begs the question: if we cannot derive values from facts, whence can values be arrived at? Can they be derived only from other values? If so, then whence are our ultimate moral values, from which all others are derived, themselves ultimately derived? Must they be simply taken on faith? 

Wilson has recently controversially argued, in his excellent Consilience: The Unity of Knowledge, that, in this context: 

The posing of the naturalistic fallacy is itself a fallacy” (Consilience: p273). 

Leaving aside this controversial claim, it is clear that his point in ‘Sociobiology’ is narrower. 

In short, Wilson seems to be arguing that, in contemplating the appropriateness of different theories of prescriptive ethics (e.g. utilitarianism, Kantian deontology), moral philosophers consult “the emotional control centers in the hypothalamus and limbic system of the brain” (p3). 

Yet these same moral philosophers take these emotions largely for granted. They treat the brain as a “black box” rather than a biological entity the nature of which is itself the subject of scientific study (p562). 

Yet, despite the criticism Wilson’s suggestion provoked among many philosophers, the philosophical implications of recognising that moral intuitions are themselves a product of the evolutionary process have since become an serious and active area of philosophical enquiry. Indeed, among the leading pioneers in this field of enquiry has been the philosopher of biology Michael Ruse, not least in collaboration Wilson himself (Ruse & Wilson 1986). 

Yet if moral philosophy must be rethought in the light of biology and the evolved nature of our psychology, then the same is also surely true of arguably the other main subfield of contemporary philosophy – namely epistemology.  

Yet Wilson’s comments regarding the relevance of sociobiological theory to epistemology are even briefer than the few sentences he devotes in his opening and closing chapters to moral philosophy, being restricted to less than a sentence – a mere five-word parenthesis in a sentence primarily discussing moral philosophy and philosophers (p3). 

However, what humans are capable of knowing is, like morality, ultimately a product of the human brain – a brain which is a itself biological entity that evolved through a process of natural selection. 

The brain, then, is designed not for discovering ‘truth’, in some abstract, philosophical sense, but rather for maximizing the reproductive success of the organism whose behaviour it controls and directs. 

Of course, for most purposes, natural selection would likely favour psychological mechanisms that produce, if not ‘truth’, then at least a reliable model of the world as it actually operates, so that an organism can modify its behaviour in accordance with this model, in order to produce outcomes that maximizes its inclusive fitness under these conditions. 

However, it is at least possible that there are certain phenomena that our brains are, through the very nature of their wiring and construction, incapable of fully understanding (e.g. quantum mechanics or the hard question of consciousness), simply because such understanding was of no utility in helping our ancestors to survive and reproduce in ancestral environments. 

The importance of evolutionary theory to our understanding of epistemology and the limits of human knowledge is, together with the relevance of evolutionary theory to moral philosophy, a theme explored in philosopher Michael Ruse’s book, Taking Darwin Seriously, and is also the principal theme of such recent works as The Case Against Reality: Why Evolution Hid the Truth from Our Eyes by Donald D Hoffman. 

Dated? 

Is ‘Sociobiology: The New Synthesis’ worth reading today? At almost 700 pages, it represents no idle investment of time. 

Wilson is a wonderful writer even in a purely literary sense, and has the unusual honour for a working scientist of being a twice Pulitzer-Prize winner. However, apart from a few provocative sections in the opening and closing chapters, ‘Sociobiology: The New Synthesis’ is largely written in the form of a student textbook, is not a book one is likely to read on account of its literary merits alone. 

As a textbook, Sociobiology is obviously dated. Indeed, the extent to which it has dated is an indication of the success of the research programme it helped inspire. 

Thus, one of the hallmarks of true science is the speed at which cutting-edge work becomes obsolete.  

Religious believers still cite holy books written millennia ago, while adherents of pseudo-sciences like psychoanalysis and Marxism still paw over the words of Freud and Marx. 

However, the scientific method is a cumulative process based on falsificationism and is moreover no respecter of persons.

Scientific works become obsolete almost as fast as they are published. Modern biologists only rarely cite Darwin. 

If you want a textbook summary of the latest research in sociobiology, I would instead recommend the latest edition of Animal Behavior: An Evolutionary Approach or An Introduction to Behavioral Ecology; or, if your primary interest is human behavior, the latest edition of David Buss’s Evolutionary Psychology: The New Science of the Mind

The continued value of ‘Sociobiology: The New Synthesis’ lies in the field, not of science, but history of science In this field, it will remain a landmark work in the history of human thought, for both the controversy, and the pioneering research, that followed in its wake. 

Endnotes

[1] Actually, ‘evolutionary psychology’ is not quite a synonym for ‘sociobiology’. Whereas the latter field sought to understand the behaviour of all animals, if not all organisms, the term ‘evolutionary psychology’ is usually employed only in relation to the study of human behaviour. It would be more accurate, then, to say ‘evolutionary psychology’ is a synonym, or euphemism, for ‘human sociobiology’.

[2] Whereas behavioural geneticists focus on heritable differences between individuals within a single population, evolutionary psychologists largely focus on behavioural adaptations that are presumed to be pan-human and universal. Indeed, it is often argued that there is likely to be minimal heritable variation in human psychological adaptations, precisely because such adaptations have been subject to such strong selection pressure as to weed out suboptimal variation, such that only the optimal genotype remains. On this view, substantial heritable variation is found only in respect of traits that have not been subject to intense selection pressure (see Tooby & Cosmides 1990). However, this fails to be take into account such phenomena as frequency dependent selection and other forms of polymorphism, whereby different individuals within a breeding population adopt, for example, quite different reproductive strategies. It is also difficult to reconcile with the finding of behavioural geneticists that there is substantial heritable variation in intelligence as between individuals, despite the fact that the expansion of human brain-size over the course of evolution suggests that intelligence has been subject to strong selection pressures.

[3] For example, in 1997, the journal Ethology and Sociobiology, which had by then become, and remains, the leading scholarly journal in the field of what would then have been termed ‘human sociobiology’, and now usually goes by the name of ‘evolutionary psychology’, changed its name to Evolution and Human Behavior.

[4] An irony is that, while science is built on the assumption of determinism, namely the assumption that observed phenomena have causes that can be discovered by controlled experimentation, one of the findings of science is that, at least at the quantum level, determinism is actually not true. This is among the reasons why quantum theory is paradoxically popular among people who don’t really like science (and who, like virtually everyone else, don’t really understand quantum theory). Thus, Richard Dawkins has memorably parodied quantum mysticism as as based on the reasoning that: 

Quantum mechanics, that brilliantly successful flagship theory of modern science, is deeply mysterious and hard to understand. Eastern mystics have always been deeply mysterious and hard to understand. Therefore, Eastern mystics must have been talking about quantum theory all along.”

[5] Indeed, although since reconciled, Wilson and Watson seem to have shared a deep personal animosity for one another, Wilson once describing how he had once considered Watson, with whom he later reconciled, “the most unpleasant human being I had ever met” – see Wilson’s autobiography, Naturalist. A student of Watson’s describes how, when Wilson was granted tenure at Harvard before Watson:

It was a big, big day in our corridor” as “Watson could be heard coming up the stairwell…  shouting ‘fuck, fuck, fuck” (Watson and DNA: p98)  

Wilson’s description of Watson’s personality in his memoir is interesting in the light of the later controversy regarding the latters comments regarding the economic implications of racial differences in intelligence, with Wilson writing: 

Watson, having risen to historic fame at an early age, became the Caligula of biology. He was given license to say anything that came to his mind and expect to be taken seriously. And unfortunately, he did so, with a casual and brutal offhandedness.” 

In contrast, geneticist David Reich suggests that Watson’s abrasive personality predated his scientific discoveries and may even have been partly responsible for them, writing: 

His obstreperousness may have been important to his success as a scientist” (Who We are and how We Got Here: p263).

[6] Group selection has recently, however, enjoyed something of a resurgence in the form of multi-level selection theory. Wilson himself is very much a supporter of this trend.

[7] Of course, it goes without saying that the persecution to which Wilson was subjected was as nothing compared to that to which Galileo was subjected (see my post, A Modern McCarthyism in Our Midst). 

References 

Nowak et al (2010) The evolution of eusociality Nature 466:1057–1062. 

Price (1996) ‘In Defence of Group Selection, European Sociobiological Society Newsletter. No. 42, October 1996 

Ruse & Wilson (1986) Moral Philosophy as Applied SciencePhilosophy 61(236):173-192 

Tooby & Cosmides (1990) On the Universality of Human Nature and the Uniqueness of the Individual: The Role of Genetics and AdaptationJournal of Personality 58(1): 17-67. 

Trivers (1971) The evolution of reciprocal altruism. Quarterly Review of Biology 46:35–57 

Donald Symons’ ‘The Evolution of Human Sexuality’: A Founding Work of Modern Evolutionary Psychology

The Evolution of Human Sexuality by Donald Symons (Oxford University Press 1980). 

Research over the last four decades in the field that has come to be known as evolutionary psychology has focused disproportionately on mating behaviour. Geoffrey Miller (1998) has even argued that it is the theory of sexual selection rather than that of natural selection which, in practice, guides most research in this field. 

This does not reflect merely the prurience of researchers. Rather, given that reproductive success is the ultimate currency of natural selection, mating behaviour is, perhaps along with parental investment, the form of behaviour most directly subject to selective pressures.

Almost all of this research traces its ancestry ultimately to Donald Symons’ ‘The Evolution of Human Sexuality’ by Donald Symons. Indeed, much of it was explicitly designed to test claims and predictions formulated by Symons himself in this very book.

Age Preferences 

For example, in his discussion of the age at which women are perceived as most attractive by males, Symons formulated two alternative hypotheses. 

First, if human evolutionary history were characterized by fleeting one-off sexual encounters (i.e. one-night standscasual sex and hook-ups), then, he reasoned, men would have evolved to find women most attractive when the latter are at the age of their maximum fertility

For women, fertility is said to peak around when a woman reaches her mid-twenties since, although women still in their teens have high pregnancy rates, they also experience greater risk of birth complications

However, if human evolutionary history were characterized instead by long-term pair bonds, then men would have evolved to be maximally attracted to somewhat younger women (i.e. those at the beginning of their reproductive careers), so that, by entering a long-term relationship with the woman at this time, a male is potentially able to monopolize her entire lifetime reproductive output (p189). 

More specifically, males would have evolved to prefer females, not of maximal fertility, but rather of maximal reproductive value, a term borrowed from demography and population genetics which refers to a person’s expected future reproductive output given their current age. Unlike fertility, a woman’s reproductive value peaks around her mid- to late-teens.  

On the basis of largely anecdotal evidence, Symons concludes that human males have evolved to be most attracted to females of maximal reproductive value rather than maximal fertility.  

Subsequent research designed to test between Symons’s rival hypotheses has largely confirmed his speculative hunch that it is younger females in their mid- to late-teens who are perceived by males as most attractive (e.g. Kenrick and Keefe 1992). 

Why Average is Attractive 

Symons is also credited as the first person to recognize that a major criterion of attractiveness is, paradoxically, averageness, or at least the first to recognize the significance of, and possible evolutionary explanation for, this discovery.[1] Thus, Symons argues that: 

[Although] health and status are unusual in that there is no such thing as being too healthy or too high ranking… with respect to most anatomical traits, natural selection produces the population mean” (p194). 

On this view, deviations from the population mean are interpreted as the result of deleterious mutations or developmental instability, and hence bad genes.[2]

Concealed Ovulation

Support has even emerged for some of Symons’ more speculative hunches. 
 
For example, one of Symons’ two proposed scenarios for the evolution of concealed ovulation, in which he professed “little confidence” (p141), was that this had evolved so as to impede male mate-guarding and enable females select a biological father for their offspring different from their husbands (p139-141). 
 
Consistent with this theory, studies have found that women’s mate preferences vary throughout their menstrual cycle in a manner compatible with a so-called ‘dual mating strategy’, preferring males evidencing a willingness to invest in offspring at most times, but, when at their most fertile, preferring characteristics indicative of genetic quality (e.g. Penton-Voak et al 1999). 

Meanwhile, a questionnaire distributed via a women’s magazine found that women engaged in extra-marital affairs do indeed report engaging in ‘extra-pair copulations’ (EPCs) at times likely to coincide with ovulation (Bellis and Baker 1990).[3]

The Myth of Female Choice

Interestingly, Symons even anticipated some of the mistakes evolutionary psychologists would be led into. 
 
Thus, he warns that researchers in modern western societies may be prone to overestimate the importance of female choice as a factor in human evolution, because, in their own societies, this is a major factor, if not the major factor, in determining marriage and sexual and romantic relationships (p203).[4]
 
However, in ancestral environments (i.e. what evolutionary psychologists now call the Environment of Evolutionary Adaptedness or EEA) arranged marriages were likely the norm, as they are in most premodern cultures around the world today (p168).[5] 
 
Thus, Symons concludes: 

“There is no evidence that any features of human anatomy were produced by intersexual selection [i.e. female choice]. Human physical sex differences are explained most parsimoniously as the outcome of intrasexual selection (the result of male-male competition)” (p203). 

Thus, human males have no obvious analogue of the peacock’s tail, but they do have substantially greater levels of upper-body strength and violent aggression as compared to females.[6]
 
This was a warning almost entirely ignored by subsequent generations of researchers before being forcefully reiterated by Puts (2010)

Homosexuality as a ‘Test-Case 

An idea of the importance of Symons’s work can be ascertained by comparing it with contemporaneous works addressing the same subject-matter. 
 
Edward O Wilson’s  On Human Nature was first published in 1978, only a year before Symons’s ‘The Evolution of Human Sexuality’. 

However, whereas Symons’s book set out much of the theoretical basis for what would become the modern science of evolutionary psychology, Wilson’s chapter on “Sex” has dated rather less well, and a large portion of chapter is devoted to introducing a now faintly embarrassing theory of the evolution of homosexuality which has subsequently received no empirical support (see Bobrow & Bailey 2001).[7] 
 
In contrast, Symons’s own treatment of homosexuality is innovative. It is also characteristic of his whole approach and illustrates why ‘The Evolution of Human Sexuality‘ has been described by David Buss as “the first major treatise on evolutionary psychology proper” (Handbook of Evolutionary Psychology: p251). 
 
Rather than viewing all behaviours as necessarily adaptive (as critics of evolutionary psychology, such as Stephen Jay Gould, have often accused sociobiologists of doing),[8] Symons instead focuses on admittedly non-adaptive (or, indeed, even maladaptive) behaviours, not because he believes them to be adaptive, but rather because they provide a unique window on the nature of human sexuality 
 
Accordingly, Symons does not concern himself with how homosexuality evolved, implicitly viewing it as a rare and maladaptive malfunctioning of normal sexuality. Yet the behaviour of homosexuals is of interest to Symons because it provides a window on the nature of male and female sexuality as it manifests itself when freed from the constraints imposed by the conflicting desires of the opposite sex. 
 
On this view, the rampant promiscuity manifested by many homosexual men (e.g. ‘cruising’ and ‘cottaging’ in bathhouses and public lavatories, or Grindr hookups) reflects the universal male desire for sexual variety when freed from the constraints imposed by the conflicting desires of women. 

This desire for sexual variety is, of course, obviously reproductively unproductive among homosexual men themselves. However, it evolved because it enhanced the reproductive success of heterosexual men by motivating them to attempt to mate with multiple females and thereby father multiple offspring. 
 
In contrast, burdened with pregnancy and lactation, women’s potential reproductive rate is more tightly constrained than that of men. They therefore have little to gain reproductively by mating with multiple males, since they can usually gestate, and nurse, only one offspring at a time. 
 
It is therefore notable that, among lesbians, there is little evidence of the sort of rampant promiscuity common among gay men. Instead, lesbian relationships seem to be characterized by much the same features as heterosexual coupling (i.e. long-term pair-bonds).
 
The similarity of heterosexual coupling to that of lesbians, and the striking contrast with that of male homosexuals, suggests that it is women, not men, who exert decisive influence in dictating the terms of heterosexual coupling.[9] 
 
Thus, Symons reports:  

There is enormous cross-cultural variation in sexual customs and laws and the extent of male control, yet nowhere in the world do heterosexual relations begin to approximate those typical of homosexual men This suggests that, in addition to custom and law, heterosexual relations are structured to a substantial degree by the nature and interests of the human female” (p300). 

This conclusion is, of course, diametrically opposite to the feminist contention that it is men who dictate the terms of heterosexual coupling and for whose exclusive benefit such relationships are structured. 
 
It also suggests, again contrary to feminist assumptions of male dominance, that most men are ultimately frustrated in achieving their sexual ambitions to a far greater extent than are most women. 

Thus, Symons concludes: 

The desire for sexual variety dooms most human males to a lifetime of unfulfilled longing” (p228). 

Here, Symons anticipates Camille Paglia who was later to famously observe: 

Men know they are sexual exiles. They wander the earth seeking satisfaction, craving and despising, never content. There is nothing in that anguished motion for women to envy” (Sexual Personae: p19). 

Criticisms of Symons’s Use of Homosexuality as a Test-Case

There is, however, a potential problem with Symons’s use of homosexual behaviour as a window onto the nature of male and female sexuality as they manifest themselves when freed from the conflicting desires of the opposite sex. The whole analysis rests on a questionable premise – namely that homosexuals are, their preference for same-sex partners aside, otherwise similar, if not identical, to heterosexuals of their own sex in their psychology and sexuality. 
 
Symons defends this assumption, arguing: 

There is no reason to suppose that homosexuals differ systematically from heterosexuals in any way other than their sexual object choice” (p292). 

Indeed, in some respects, Symons seems to see even “sexual object choice” as analogous among homosexuals and heterosexuals of the same sex. 
 
For example, he observes that, unlike women, both homosexual and heterosexual men tend to evaluate prospective mates primarily on the basis their physical appearance and youthfulness (p295). 

Thus, in contrast to the failure of periodicals featuring male nudes to attract a substantial female audience (see below), Symons notes the existence of a market for gay pornography parallel in most respects to heterosexual porn – i.e. featuring young, physically attractive models in various states of undress (p301). 
 
This, of course, contradicts the feminist notion that men are led to ‘objectify’ women only due to the sexualized portrayal of the latter in the media. 
 
Instead, Symons concludes: 

That homosexual men are at least as likely as heterosexual men to be interested in pornography, cosmetic qualities and youth seems to me to imply that these interests are no more the result of advertising than adultery and alcohol consumption are the result of country and western music” (p304).[10] 

However, this assumption of the fundamental similarity of heterosexual and homosexual male psychology has been challenged by David Buller in his book, Adapting Minds: Evolutionary Psychology and the Persistent Quest for Human Nature
 
Buller cites evidence that male homosexuals are ‘feminized’ in many aspects of their behaviour.

Thus, one of the few consistent early correlates of homosexuality is gender non-conformity in childhood and some evidence (e.g. digit ratios, the fraternal birth order effect) has been interpreted to suggest that the level of prenatal exposure to masculinizing androgens (e.g. testosterone) in utero affects sexual orientation.
 
As Buller notes, although gay men seem, like heterosexual men, to prefer youthful sexual partners, they also appear to prefer sexual partners who are, in other respects highly masculine.[11]

Thus, Buller observes: 

“The males featured in gay men’s magazines embody very masculine, muscular physiques, not pseudo-feminine physiques” (Adapting Minds: p227).

Indeed, the models in such magazines seem in most respects similar in physical appearance to the male models, pop stars, actors and other ‘sex symbols’ and celebrities fantasized about by heterosexual women and girls.
 
How then are we to resolve this apparent paradox? 
 
One possible explanation that some aspects of the psychology of male homosexuals are feminized but not others – perhaps because different parts of the brain are formed at different stages of prenatal development, at which stages the levels of masculinizing androgens in the womb may vary. 
 
Indeed, there is even some evidence that homosexual males may be hyper-masculinized in some aspects of their physiology.

For example, it has been found that homosexual males report larger penis-sizes than heterosexual men (Bogaert & Hershberger 1999). 
 
This, researchers Glenn Wilson and Qazi Rahman propose, may be because: 

If it is supposed that the barriers against androgens with respect to certain brain structures (notably those concerned with homosexuality) lead to increased secretion in an effort to break through, or some sort of accumulation elsewhere… then there may be excess testosterone left in other departments” (Born Gay: The Psychobiology of Sex Orientation: p80). 

Another possibility is that male homosexuals actually lie midway between heterosexual men and women in their degree of masculinization.  

On this view, homosexual men come across as relatively feminine only because we naturally tend to compare them to other men (i.e. heterosexual men). However, as compared to women, they may be relatively masculine, as reflected in the male-typical aspects of their sexuality focused upon by Symons. 
 
Interestingly, this latter interpretation suggests the slightly disturbing possibility that, freed from the restraints imposed by women, heterosexual men would be even more indiscriminately promiscuous than their homosexual counterparts.

Evidence consistent with this interpretation is provided by one study from the 1980s which found that, when approached by a female stranger (also a student), on a University campus, with a request to go to bed with them, fully 72% of male students agreed (Clark and Hatfield 1989). 

In contrast, in the same study, not a single one of the 96 females approached by male strangers with the same request on the same university campus agreed to go to bed with the male stranger.

Yet what percentage of the female students subsequently sued the university for sexual harassment was not reported.

Pornography as a “Natural Experiment

For Symons, fantasy represents another window onto sexual and romantic desires. Like homosexuality, fantasy is, by its very nature, unconstrained by the conflicting desires of the opposite sex (or indeed by anything other than the imagination of the fantasist). 

Symons later collaborated in an investigation into sexual fantasy by means of a questionnaire (Ellis and Symons 1990). 

However, in the present work, he investigates fantasy indirectly by focusing on what he calls “the natural experiment of commercial periodical publishing” – i.e. pornographic magazines (p182). 
 
In many respects, this approach is preferable to a survey because, even in an anonymous questionnaire, individuals may be less than honest when dealing with a sensitive topic such as their sexual fantasies. On the other hand, they are unlikely to regularly spend money on a magazine unless they are genuinely attracted by its contents. 
 
Before the internet age, softcore pornographic magazines, largely featuring female nudes, commanded sizeable circulations. However, their readership (if indeed ‘readership’ is the right words, since there was typically little reading involved) was almost exclusively male. 
 
In contrast, there was little or no female audience for magazines containing pictures of naked males. Instead, magazines marketed towards women (e.g. fashion magazines) contain, mostly, pictures of other women. 
 
Indeed, when, in the 1970s, attempts were made, in the misguided name of feminism and ‘women’s liberation’, to market magazines featuring male nudes to a female readership, one such title, Viva, abandoned publishing male nudes after just a few years due to lack of interest or demand, then subsequently went bust just a few years after that, while the other, Playgirl, although it did not entirely abandon male nudes, was notorious, as a consequence, for attracting a readership composed in large part of homosexual men. 
 
Symons thus concludes forcefully and persuasively: 

The notion must be abandoned that women are simply repressed men waiting to be liberated” (p183). 

Indeed, though it has been loudly and enthusiastically co-opted by feminists, this view of women, and of female sexuality – namely women as “repressed men waiting to be liberated” – represents an obviously quintessentially male viewpoint. 

Indeed, taken to extremes, it has even been used as a justification for rape.

Thus, the curious, sub-Freudian notion that female rape victims actually secretly enjoy being raped seems to rest ultimately on the assumption that female sexuality is fundamentally the same as that of men (i.e. indiscriminately enjoying of promiscuous sex) and that it is only women’s sexual ‘repression’ that prevents them admitting as much.

Romance Literature 

Unfortunately, however, there is notable omission in Symons’s discussion of pornography as a window into male sexuality – namely, he omits to consider whether there exists any parallel artistic genre that offers equivalent insight into the female psyche. 
 
Later writers on the topic have argued that romance novels (e.g. Mills and Boon, Jane Austin), whose audience is as overwhelmingly female as pornography’s is male, represent the female equivalent of pornography, and that analysis of the the content of such works provides insights into female mate preferences parallel to those provided into male psychology by pornography (e.g. Kruger et al 2003; Salmon 2004; see also Warrior Lovers: Erotic Fiction, Evolution and Female Sexuality, co-authored by Symons himself). 

Female Orgasm as Non-Adaptive

An entire chapter of ‘The Evolution of Human Sexuality’, namely Chapter Three (entitled, “The Female Orgasm: Adaptation or Artefact”), is devoted to rejecting the claim that the female orgasm represents a biological adaptation. 
 
This is perhaps excessive. However, it does at least conveniently contradicts the claim of some critics of evolutionary psychology, and of sociobiology, such as Stephen Jay Gould that the field is ‘ultra-Darwinian’ or ‘hyper-adaptionist’ and committed to the misguided notion that all traits are necessarily adaptive.[12]
 
In contrast, Symons champions the thesis that the female capacity for orgasm is a simply non-adaptive by-product of the male capacity to orgasm, the latter of which is of course adaptive. 
 
On this view, the female orgasm (and clitoris) is, in effect, the female equivalent of male nipples (only more fun). 
 
Certainly, Symons convincingly critiques the romantic notion, popularized by Desmond Morris among others, that the female orgasm functions as a mechanism designed to enhance ‘pair-bonding’ between couples. 
 
However, subsequent generations of evolutionary psychologists have developed less naïve models of the adaptive function of female orgasm. 
 
For example, Geoffrey Miller argues that the female orgasm functions as an adaptation for mate choice (The Mating Mind: p239-241). 
 
Of course, at first glance, experiencing orgasm during coitus may appear to be a bit late for mate choice, since, by the time coitus has occurred, the choice in question has already been made. However, given that, among humans, most sexual intercourse is non-reproductive (i.e. does not result in conception), the theory is not altogether implausible. 
 
On this view, the very factors which Symons views as suggesting female orgasm is non-adaptive – such as the relative difficultly of stimulating female orgasm during ordinary vaginal sex – are positive evidence for its adaptive function in carefully discriminating between suitors/lovers to determine their desirability as father for a woman ’s offspring. 
 
Nevertheless, at least according to the stringent criteria set out by George C Williams in his classic Adaptation and Natural Selection, as well as the more general principle of parsimony (also known as Occam’s Razor), the case for female orgasm as an adaptation remains unproven (see also Sherman 1989; Case Of The Female Orgasm: Bias in the Science of Evolution).

Out-of-Date?

Much of Symons’ work is dedicated to challenging the naïve group-selectionism of Sixties ethologists, especially Desmond Morris. Although scientifically now largely obsolete, Morris’s work still retains a certain popular resonance and therefore this aspect of Symons’s work is not entirely devoid of contemporary relevance. 
 
In place of Morris‘s rather idyllic notion that humans are a naturally monogamous ‘pair-bonding’ species, Symons advocates instead an approach rooted in the individual-level (or even gene-level) selection championed Richard Dawkins in The Selfish Gene (reviewed here). 
 
This leads to some decidedly cynical conclusions regarding the true nature of sexual and romantic relations among humans. 
 
For example, Symons argues that it is adaptive for men to be less sexually attracted to their wives than they are to other women – because they are themselves liable to bear the cost of raising offspring born to their wives but not those born to other women with whom they mate (e.g. those mated to other males). 
 
Another cynical conclusion is that the primary emotion underlying the institution of marriage, both cross-culturally and in our own society, is neither love nor even lust, but rather male sexual jealousy and proprietariness (p123). 

Marriage, then, is an institution borne not of love, but of male sexual jealousy and the behaviour known to biologists as mate-guarding
 
Meanwhile, in his excellent chapter on ‘Copulation as a Female Service’ (Chapter Eight), Symons suggests that many aspects of heterosexual romantic relationships may be analogous to prostitution
 
As well as its excessive focus on debunking sixties ethologists like Morris, ‘The Evolution of Human Sexuality’ is also out-of-date in a more serious respect Namely, it fails to incorporate the vast amount of empirical research on human sexuality from a sociobiological perspective which has been conducted since the first publication of his work. 
 
For a book first published thirty years ago, this is inevitable – not least because much of this empirical research was inspired by Symons’ own ideas and specifically designed to test theories formulated in this very work. 
 
In addition, potentially important new factors in human reproductive behaviour that even Symons did not foresee have been identified, for example role of levels of fluctuating asymmetry functioning as a criterion for, or at least correlate of, physical attractiveness. 
 
For an updated discussion of the evolutionary psychology of human sexual behaviour, complete with the latest empirical data, readers should consult the latest edition of David Buss’s The Evolution Of Desire: Strategies of Human Mating
 
In contrast, in support of his theories Symons relies largely on classical literary insight, anecdote and, most importantly, a review of the ethnographic record. 
 
However, this latter focus ensures that, in some respects, the work remains of more than merely of historical interest. 
 
After all, one of the more legitimate criticisms levelled against recent research in evolutionary psychology is that it is insufficiently cross-cultural and, with several notable exceptions (e.g. Buss 1989), relies excessively on research conducted among convenience samples of students at western universities. 
 
Given costs and practicalities, this is inevitable. However, for a field that aspires to understand a human nature presumed to be universal, such a method of sampling is highly problematic. 
 
The Evolution of Human Sexuality’ therefore retains its importance for two reasons. 

First, is it the founding work of modern evolutionary psychological research into human sexual behaviour, and hence of importance as a landmark and classic text in the field, as well as in the history of science more generally. 

Second, it also remains of value to this day for the cross-cultural and ethnographic evidence it marshals in support of its conclusions. 

Endnotes

[1] Actually, the first person to discover this, albeit inadvertently, was the great Victorian polymath, pioneering statistician and infamous eugenicist Francis Galton, who, attempting to discover abnormal facial features possessed by the criminal class, succeeded in morphing the faces of multiple convicted criminals. The result was, presumably to his surprise, an extremely attractive facial composite, since all the various minor deformities of the many convicted criminals whose faces he morphed actually balanced one another out to produce a face with few if any abnormalities or disproportionate features.

[2] More recent research in this area has focused on the related concept of fluctuating asymmetry.

[3] However, recent meta-analyses have called into question the evidence for cyclical fluctuations in female mate preferences (Wood et al 2014; cf. Gildersleeve et al 2014), and it has been suggested that such findings may represent casualties of the so-called replication crisis in psychology. It has also been questioned whether ovulation in humans is indeed concealed, or is actually detectable by subtle cues (e.g. Miller et al 2007), for example, changes in face shape (Oberzaucher et al 2012), breast symmetry (Scutt & Manning 1996) and body scent (Havlicek et al 2006).

[4] Another factor leading recent researchers to overestimate the importance of female choice in human evolution is their feminist orientation, since female choice gives women an important role in human evolution, even, paradoxically, in the evolution of male traits.

[5] Actually, in most cultures, only a girl’s first marriage is arranged on her behalf by her parents. Second- and third-marriages are usually negotiated by the woman herself. However, since female fertility peaks early, it is a girl’s first marriage that is usually of the most reproductive, and hence Darwinian, significance.

[6] Indeed, the human anatomical trait in humans that perhaps shows the most evidence of being a product of intersexual selection is a female one, namely the female breasts, since the latter are, unlike the mammary glands of most other mammals, permanently present from puberty on, not only during lactation, and composed primarily of fatty tissues, not milk (Møller 1995; Manning et al 1997; Havlíček et al 2016

[7] Wilson terms his theory “the kin selection theory hypothesis of the origin of homosexuality” (p145). However, a better description might be the ‘helper at the nest theory of homosexuality’, the basic idea being that, like sterile castes in some insects, and like older siblings in some bird species where new nest sites are unavailable, homosexuals, rather than reproducing themselves, direct their energies towards assisting their collateral kin in successfully raising, and provisioning, their own offspring (p143-7). The main problem with this theory is that there is no evidence that homosexuals do indeed devote any greater energies towards assisting their kin in this respect. On the contrary, homosexuals instead seem to devote much of their time and resources towards their own sex life, much as do heterosexuals (Bobrow & Bailey 2001).

[8] As we will see, contrary to the stereotype of evolutionary psychologists as viewing all traits as necessarily adaptive, as they are accused of doing by the likes of Gould, Symons also argued that the female orgasm and menopause are non-adaptive, but rather by-products of other adaptations.

[9] This is not necessarily to say that rampant, indiscriminate promiscuity is a male utopia, or the ideal of any man, be he homosexual or heterosexual. On the contrary, the ideal mating system for any individual male is harem polygyny in which the chastity of his own partners is rigorously policed (see Despotism and Differential Reproduction: which I have reviewed here and here). However, given an equal sex ratio, this would condemn other males to celibacy. Similarly, Symons reports that “Homosexual men, like most people, usually want to have intimate relationships”. However, he observes:

Such relationships are difficult to maintain, largely owing to the male desire for sexual variety; the unprecedented opportunity to satisfy this desire in a world of men, and the male tendency towards sexual jealousy” (p297).  

It does indeed seem to be true that homosexual relationships, especially those of gay males, are, on average, of shorter duration than are heterosexual relationships. However, Symons’ claim regarding “the male tendency towards sexual jealousy” is questionable. Actually, subsequent research in evolutionary psychology has suggested that men are no more prone to jealousy than women, but rather that it is sorts of behaviours which most intensely provoke such jealousy that differentiate the sexes (Buss 1992). However, many gay men practice open relationships, which seems to suggest a lack of jealousy – or perhaps this simply reflects a recognition of the difficulty of maintaining relationships given, as Symons puts it, “the male desire for sexual variety [and] the unprecedented opportunity to satisfy this desire in a world of men”. 

[10] Indeed, far from men being led to objectify women due to the portrayal of women in a sexualized manner in the media, Symons suggests:

There may be no positive feedback at all; on the contrary, constant exposure to pictures of nude and nearly nude female bodies may to some extent habituate men to these stimuli” (p304).

[11] Admittedly, some aspects of body-type typically preferred by gay males (especially the twink) do reflect apparently female traits, especially a relative lack of body-hair. However, lack of body-hair is also obviously indicative of youth. Moreover, a relative lack of body-hair also seems to be a trait favoured in men by heterosexual women. For a discussion of the relative preference on the part of (heterosexual) females for masculine versus feminine traits in male sex partners, see the final section of this review.

[12] Incidentally, Symons also rejects the theory that the female menopause is adaptive, a theory which has subsequently become known as the grandmother hypothesis (p13). Also, although it does not directly address the issue, Symons’ discussion of human rape (p276-85), has also been interpreted as implicitly favouring the theory that rape is a by-product of the greater male desire for commitment free promiscuous sex, rather than the product of a specific rape adaptation in males (see Palmer 1991; and A Natural History of Rape: reviewed here). 

References 

Bellis & Baker (1990). Do females promote sperm competition?: Data for humans. Animal Behavior, 40: 997-999 
Bobrow & Bailey (2001). Is male homosexuality maintained via kin selection? Evolution and Human Behavior, 22: 361-368 
Bogaert & Hershberger (1999) The relation between sexual orientation and penile size. Archives of Sexual Behavior 1999 Jun;28(3) :213-21. 
Buss (1989). Sex differences in human mate preferences: Evolutionary hypotheses tested in 37 cultures. Behavioral and Brain Sciences 12: 1-49 
Ellis & Symons (1990) Sex differences in sexual fantasy: An evolutionary psychological approach, Journal of Sex Research 27(4): 527-555.
Gildersleeve, Haselton & Fales (2014) Do women’s mate preferences change across the ovulatory cycle? A meta-analytic review. Psychological Bulletin 140(5):1205-59.
Havlíček, Dvořáková, Bartos & Fleg (2006) Non‐Advertized does not Mean Concealed: Body Odour Changes across the Human Menstrual Cycle. Ethology 112(1):81-90.
Havlíček et al (2016) Men’s preferences for women’s breast size and shape in four cultures. Evolution and Human Behavior 38(2): 217–226 
Kenrick & Keefe (1992). Age preferences in mates reflect sex differences in human reproductive strategies. Behavioral and Brain Sciences, 15: 75-133. 
Kruger et al (2003) Proper and Dark Heroes as Dads and Cads. Human Nature 14(3): 305-317 
Manning et al (1997) Breast asymmetry and phenotypic quality in women. Ethology and Sociobiology 18(4): 223–236 
Miller (1998). How mate choice shaped human nature: A review of sexual selection and human evolution. In C. Crawford & D. Krebs (Eds.), Handbook of Evolutionary Psychology: Ideas, Issues, and Applications (pp. 87-129). Mahwah, NJ: Lawrence Erlbaum
Miller, Tybur & Jordan (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrous? Evolution and Human Behavior. 28(6):375–381 
Møller et al (1995) Breast asymmetry, sexual selection, and human reproductive success. Ethology and Sociobiology 16(3): 207-219 
Palmer (1991) Human Rape: Adaptation or By-Product? Journal of Sex Research 28(3): 365-386 
Penton-Voak et al (1999) Menstrual cycle alters face preferences, Nature 399 741-2. 
Puts (2010) Beauty and the Beast: Mechanisms of Sexual Selection in Humans. Evolution and Human Behavior 31 157-175 
Salmon (2004) The Pornography Debate: What Sex Differences in Erotica Can Tell Us About Human Sexuality. In Evolutionary Psychology, Public Policy and Personal Decisions (London: Lawrence Erlbaum Associates, 2004) 
Scutt & Manning (1996) Symmetry and ovulation in women. Human Reproduction 11(11):2477-80
Sherman (1989) The clitoris debate and levels of analysis, Animal Behaviour, 37: 697-8
Wood et al (2014). Meta-analysis of menstrual cycle effects on women’s mate preferencesEmotion Review, 6(3), 229–249.

Richard Dawkins’ ‘The Selfish Gene’: Selfish Genes, Selfish Memes and Altruistic Phenotypes

[In the process of resurrecting this long inactive blog, I have decided to start posting, among other things, full extended versions (i.e. vastly overlong versions) of my Amazon and Goodreads book reviews, since these, being vastly overlong, usually have to edited in order to comply with the amazon and Goodreads word-limits. I start, however, with a relatively shorter review (by my standards) of a favourite book, namely Richard Dawkins’ ‘The Selfish Gene’.]
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‘The Selfish Gene’, by Richard Dawkins, Oxford University Press, 1976.

Selfish Genes ≠ Selfish Phenotypes

Richard Dawkins’s ‘The Selfish Gene’ is among the most celebrated, but also the most misunderstood, works of popular science.

Thus, among people who have never read the book (and, strangely, a few who apparently have) Dawkins is widely credited with arguing that humans are inherently selfish, that this disposition is innate and inevitable, and even, in some versions, that behaving selfishly is somehow justified by our biological programming, the titular ‘Selfish Gene’ being widely misinterpreted as referring to a gene that causes us to behave selfishly.

Actually, Dawkins is not concerned, either directly or primarily, with humans at all.

Indeed, he professes to be “not really very directly interesting in man”, whom he dismisses as “a rather aberrant species” and hence peripheral to his own interest, namely how evolution has shaped the bodies and especially the behaviour of organisms in general (Dawkins 1981: p556).

‘The Selfish Gene’ is then, unusually, if not uniquely, for a bestselling work of popular science, a work, not of human biology nor even of non-human zoology, ethology or natural history, but rather of theoretical biology.

Moreover, in referring to genes as ‘selfish’, Dawkins has in mind not a trait that genes encode in the organisms they create, but rather a trait of the genes themselves.

In other words, individual genes are themselves conceived of as ‘selfish’ (in a metaphoric sense), in so far as they have evolved by natural selection to selfishly promote their own survival and replication by creating organisms designed to achieve this end.

Indeed, ironically, as Dawkins is at pains to emphasise, selfishness at the genetic level can actually result in altruism at the level of the organism or phenotype.

This is because, where altruism is directed towards biological kin, such altruism can facilitate the replication of genes shared among relatives by virtue of their common descent. This is referred to as kin selection or inclusive fitness theory and is one of the central themes of Dawkins’ book.

Yet, despite this, Dawkins still seems to see organisms themselves, humans very much included, as fundamentally selfish – albeit a selfishness tempered by a large dose of nepotism.

Thus, in his opening paragraphs no less, he cautions:

If you wish, as I do, to build a society in which individuals cooperate generously and unselfishly towards a common good, you can expect little help from our biological nature. Let us try to teach generosity and altruism, because we are born selfish” (p3).

The Various Editions

In later editions of his book, namely those published since 1989, Dawkins tempers this rather cynical view of human and animal behaviour by the addition of a new chapter – Chapter 12, titled ‘Nice Guys Finish First’.

This new chapter deals with the subject of reciprocal altruism, a topic he had actually already discussed earlier, together with the related, but distinct, phenomenon of mutualism,[1] in Chapter 10 (entitled, ‘You Scratch My Back, I’ll Ride on Yours’).

In this additional chapter, he essentially summarizes the work of political scientist Robert Axelrod, as discussed in Axelrod’s own book The Evolution of Co-Operation. This deals with evolutionary game theory, specifically the iterated prisoner’s dilemma, and the circumstances in which a cooperative  strategy can, by cooperating only with those who have a history of reciprocating, survive, prosper, evolve, and, in the long-term, ultimately outcompete  and hence displace those strategies which maximize only short-term self-interest.

Post-1989 editions also include another new chapter titled ‘The Long Reach of the Gene’ (Chapter 13).

If, in Chapter 12, the first additional chapter, Dawkins essentially summarised the contents of of Axelrod’s book, The Evolution of Cooperation, then, in Chapter 13, he summarizes his own book, The Extended Phenotype.

In addition to these two additional whole chapters, Dawkins also added extensive endnotes to these post-1989 editions.

These endnotes clarify various misunderstandings which arose from how he explained himself in the original version, defend Dawkins against some criticisms levelled at certain passages of the book and also explain how the science progressed in the years since the first publication of the book, including identifying things he and other biologists got wrong.

With still more recent new editions, the content of ‘The Selfish Gene’ has burgeoned still further. Thus, he 30th Anniversary Edition boasts only a new introduction; the recent 40th Anniversary Edition, published in 2016, boasts a new Epilogue too. Meanwhile, the latest so-called Extended Selfish Gene boasts, in addition to this, two whole new chapters.

Actually, these two new chapters are not that new, being lifted wholesale from, once again, The Extended Phenotype, a work whose contents Dawkins has already, as we have seen, summarized in Chapter 13 (‘The Long Reach of the Gene’), itself an earlier addition to the book’s seemingly ever expanding contents list.

The decision not to entirely rewrite ‘The Selfish Gene’ was apparently that of Dawkins’ publisher, Oxford University Press.

This was probably the right decision. After all, ‘The Selfish Gene’ is not a mere undergraduate textbook, in need of revision every few years in order to keep up-to-date with the latest published research.

Rather, it was a landmark work of popular science, and indeed of theoretical biology, that introduced a new approach to understanding the evolution of behaviour and physiology to a wider readership, composed of biologist and non-biologist alike, and deserves to stand in its original form as a landmark in the history of science.

However, while the new introductions and the new epilogue is standard fare when republishing a classic work several years after first publication, the addition of four (or two, depending on the edition) whole new chapters strikes me less readily defensible.

For one thing, they distort the structure of the book, and, though interesting in and of themselves, always read for me rather as if they have been tagged on at the end as an afterthought – as indeed they have.

The book certainly reads best, in a purely literary sense, in its original form (i.e. pre-1989 editions), where Dawkins concludes with an optimistic, if fallacious, literary flourish (see below).

Moreover, these additional chapters reek of a shameless marketing strategy, designed to deceive new readers into paying the full asking price for a new edition, rather than buying a cheaper second-hand copy or just keeping their old one.

This is especially blatant in respect of the book’s latest incarnation, The Extended Selfish Gene, which, according to the information of Oxford University Press’s website, was released only three months after the previous 40th Anniversary Edition yet includes two additional chapters.

One frankly expects better from so celebrated a publisher such as Oxford University Press, and indeed so celebrated a biologist and science writer as Richard Dawkins, especially as I suspect neither are especially short of money.

If I were recommending someone who has never read the book before on which edition to buy, I would probably advise them to get a second-hand copy of any post-1989 editions, since these can now be picked up very cheap, and include the additional endnotes which I found personally very interesting.

On the other hand, if you want to read three additional chapters either from or about The Extended Phenotype then you are probably best to buy, instead, well… The Extended Phenotype – as this is also now a rather old book of which, as with ‘The Selfish Gene’, old copies can now be picked up very cheap.

The ‘Gene’s-Eye-View’ of Evolution

The Selfish Gene is a seminal work in the history of biology primarily because Dawkins takes the so-called ‘gene’s-eye-view’ of evolution to its logical conclusion. To this extent, contrary to popular opinion, Dawkins’ exposition is not merely a popularization, but actually breaks new ground theoretically.

Thus, John Maynard Smith famously talked of ‘kin selection’ by analogy with ‘group selection’ (Smith 1964). Meanwhile, William Hamilton, who formulated the theory underlying these concepts, always disliked the term ‘kin selection’ and talked instead of the ‘direct’, ‘indirect’ and ‘inclusive fitness’ of organisms (Hamilton 1964a; 1964b).

However, Dawkins takes this line of thinking to its logical conclusion by looking – not at the fitness or reproductive success of organisms or phenotypes – but rather at the success in self-replication of genes themselves.

Thus, although he certainly stridently rejects group-selection, Dawkins replaces this, not with the familiar individual-level selection of classical Darwinism, but rather with a new focus on selection at the level of the gene itself.

Abstract Animals?

Much of the interest, and no little of the controversy, arising from ‘The Selfish Gene’ concerned, of course, its potential application to human behaviour. However, in the book itself, humans, whom, as mentioned above, Dawkins dismisses as a “rather aberrant species” in which he professes to be “not really very directly interested” (Dawkins 1981: p556) are actually mentioned only occasionally and briefly.

Indeed, most of the discussion is purely theoretical. Even the behaviour of non-human animals is described only for illustrative purposes, and even these illustrative examples often involve simplified hypothetical creatures rather than descriptions of the behaviour of real organisms.

For example, he illustrates his discussion of the relative pros and cons of either fighting or submitting in conflicts over access to resources by reference to ‘hawks’ and ‘doves’ – but is quick to acknowledge that these are hypothetical and metaphoric creatures, with no connection to the actual bird species after whom they are named:

The names refer to conventional human usage and have no connection with the habits of the birds from whom the names are derived: doves are in fact rather aggressive birds” (p70).

Indeed, even Dawkins’ titular “selfish genes” are rather abstract and theoretical entities. Certainly, the actual chemical composition and structure of DNA is of only peripheral interest to him.

Indeed, often he talks of “replicators” rather than “genes” and is at pains to point out that selection can occur in respect of any entity capable of replication and mutation, not just DNA or RNA. (Hence his introduction of the concept of memes: see below).

Moreover, Dawkins uses the word ‘gene’ in a somewhat different sense to the way the word is employed by most other biologists. Thus, following George C. Williams in Adaptation and Natural Selection, he defines a “gene” as:

Any portion of chromosomal material that potentially lasts for enough generations to serve as a unit of natural selection” (p28).

This, of course, makes his claim that genes are the principle unit of selection something approaching a tautology or circular argument.

Sexual Selection in Humans?

Where Dawkins does mention humans, it is often to point out the extent to which this “rather aberrant species” apparently conspicuously fails to conform to the predictions of selfish-gene theory.

For example, at the end of his chapter on sexual selection (Chapter 9: “Battle of the Sexes”) he observes that, in contrast to most other species, among humans, at least in the West, it seems to be females who are most active in using physical appearance as a means of attracting mates:

One feature of our own society that seems decidedly anomalous is the matter of sexual advertisement… It is strongly to be expected on evolutionary grounds that where the sexes differ, it should be the males that advertise and the females that are drab… [Yet] there can be no doubt that in our society the equivalent of the peacock’s tail is exhibited by the female, not the male” (p164).

Thus, among most other species, it is males who have evolved more elaborate plumages and other flashy, sexually selected ornaments. In contrast, females of the same species are often comparatively drab in appearance.

Yet, in modern western societies, Dawkins observes, it is more typically women who “paint their faces and glue on false eyelashes” (p164).

Here, it is notable that Dawkins, being neither an historian nor an anthropologist, is careful to restricts his comments to “our own society” and, elsewhere, to “modern western man”.

Thus, one explanation is that it is only our own ‘WEIRD’, western societies that are anomalous?

Thus, Matt Ridley, in The Red Queen, proposes that maybe:

Modern western societies have been in a two-century aberration from which they are just emerging. In Regency England, Louis XIV’s France, medieval Christendom, ancient Greece, or among the Yanomamö, men followed fashion as avidly as women. Men wore bright colours, flowing robes, jewels, rich materials, gorgeous uniforms, and gleaming, decorated armour. The damsels that knights rescued were no more fashionably accoutred than their paramours. Only in Victorian times did the deadly uniformity of the black frock coat and its dismal modern descendant, the grey suit, infect the male sex, and only in this century have women’s hemlines gone up and down like yo-yos” (The Red Queen: p292).

There is an element of truth here. However, I suspect it partly reflects a misunderstanding of the different purposes for which men and women use clothing, including bright and elaborate clothing.

Thus, it rather reminds me of Margaret Mead’s claim that, among the Tschambuli of Papua New Guinea, sex-roles were reversed because, here, it was men who painted their faces and wore ‘make-up’, not women.

Yet what Mead neglected to mention that the ‘make-up’ in question that Mead found so effeminate was actually war-paint that a Tschambuli warrior was only permitted to wear after killing his first enemy warrior (see Homicide: Foundations of Human Behavior: p152).

Of course, clothes and makeup are an aspect of behaviour rather than morphology, and thus more directly analogous to, say, the nests (or, more precisely, the bowers) created by male bowerbirds than the tail of the peacock.

However, behaviour is, in principle, no less subject to natural selection (and sexual selection) than is morphology, and therefore the paradox remains.

Moreover, even focusing exclusively on morphology, the sex difference still seems to remain.

Thus, perhaps the closest thing to a ‘peacock’s tail’ in humans (i.e. a morphological trait designed to attract mates) is a female trait, namely breasts.

Thus, as Desmond Morris first observed, in humans, the female breasts seem to have been co-opted for a role in sexual selection, since, unlike among other mammals, women’s breasts are permanent, from puberty on, not present only during lactation, and composed primarily of fatty tissues, not milk (Møller 1995; Manning et al 1997; Havlíček et al 2016).

In contrast, men possess no obvious equivalent of the ‘peacock’s tail’ (i.e. a trait that has evolved in response to female choice) – though Geoffrey Miller makes a fascinating (but ultimately unconvincing) case that the human brain may represent a product of sexual selection (see The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature).[2]

Interestingly, in an endnote to post-1989 editions of ‘The Selfish Gene’, Dawkins himself tentatively speculates that maybe the human penis might represent a sexually-selected ‘fitness indicator’.

Thus, he points out that the human penis is large as compared to that of other primates, yet also lacks a baculum (i.e. penis bone) that facilitates erections. This, he speculates, could mean that the capacity to maintain an erection might represent an honest signal of health in accordance with Zahavis handicap principle (307-8).

However, it is more likely that the large size, or more specifically the large width, of the human penis reflects instead a response to the increased size of the vagina, which itself increased in size to enable human females to give birth to large-brained, and hence large-headed, infants (see Bowman 2008; Sexual Selection and the Origins of Human Mating Systems: pp61-70).[3]

How then can we make sense of this apparent paradox, whereby, contrary to Bateman’s principle, sexual selection appears to have operated more strongly on women than on men?

For his part, Dawkins himself offers no explanation, merely lamenting:

What has happened in modern western man? Has the male really become the sought-after sex, the one that is in demand, the sex that can afford to be choosy? If so, why?” (p165).

However, in respect of what David Buss calls short-term mating strategies (i.e. casual sex, hook-ups and one night stands), this is certainly not the case.

On the contrary, patterns of everything from prostitution and rape to erotica and pornography consumption confirm that, in respect of short-term ‘commitment’-free casual sex, it remains women who are very much in demand and men who are the ardent pursuers (see The Evolution of Human Sexuality: which I have reviewed here).

Thus, in one study conducted on a University campus, 72% of male students agreed to go to bed with a female stranger who approached them with a request to this effect. In contrast, not a single one of the 96 females approached agreed to the same request from a male questioner (Clark and Hatfield 1989).

(What percentage of the students sued the university for sexual harassment was not revealed.)

However, humans also form long-term pair-bonds to raise children, and, in contrast to males of most other mammalian species, male parents often invest heavily in the offspring of such unions.

Men are therefore expected to be relatively choosier in respect of long-term romantic partners (e.g. wives) than they are for casual sex partners. This may then explain the relatively high levels of reproductive competition engaged in by human females, including high levels of what Dawkins calls ‘sexual advertising’.

Reproductive competition between women may be especially intense in western societies practising what Richard Alexander termed ‘socially-imposed monogamy’.

This refers to societies where there are large differences between males in social status and resource holdings, but where even wealthy males are prohibited by law from marrying multiple women at once.[4]

Here, there may be intense competition as between females for exclusive rights to resource-abundant ‘alpha male’ providers (Gaulin and Boser 1990).

Thus, to some extent, the levels of sexual competition engaged in by women in western societies may indeed be higher than in non-western, polygynous societies.

This, then, might explain why females use what Dawkins terms ‘sexual advertising’ to attract long-term mates (i.e. husbands). However, it still fails to explain why males don’t – or, at least, don’t seem to do so to anything like the same degree.

The answer may be that, in contrast to mating patterns in modern western societies, ‘female choice’ may actually have played a surprisingly limited role in human evolutionary history, given that, in most pre-modern societies, arranged marriages were, and are, the norm.

Male mating competition may then have taken the form of ‘male-male contest competition’ (i.e. fighting) rather than displaying to females – i.e. what Darwin called intra-sexual selection’ rather than ‘inter-sexual selection’.

Thus, while men indeed possess no obvious analogue to the peacock’s tail, they do seem to possess traits designed for fighting – namely considerably greater levels of upper-body musculature and violent aggression as compared to women (see Puts 2010).

In other words, human males may not have any obvious ‘peacock’s tail’, but we perhaps we do have, if you like, ‘stag’s antlers’.

From Genes to Memes

Dawkins’ eleventh chapter, which was, in the original version of the book (i.e. pre-1989 editions), the final chapter, is also the only chapter to focus exclusively on humans.

Entitled ‘Memes: The New Replicators’, it focuses again on the extent to which humans are indeed an “aberrant species”, being subject to cultural as well as biological evolution to a unique degree.

Interestingly, however, Dawkins argues that the principles of natural selection discussed in the preceding chapters of the book can be applied just as usefully to cultural evolution as to biological evolution.

In doing so, he coins the concept of the ‘meme’ as the cultural unit of selection, equivalent to a gene, passing between minds analogously to a virus.

This term has been enormously influential in intellectual discourse, and indeed in popular discourse, and even passed into popular usage.

The analogy of memes to genes makes for an interesting thought-experiment. However, like any analogy, it can be taken too far.

Certainly ideas can be viewed as spreading between people, and as having various levels of fitness depending on the extent to which they catch on.

Thus, to take one famous example, Dawkins famously described religions to ‘Viruses of the Mind’, which travel between, and infect, human minds in a manner analogous to a virus.

Thus, proponents of Darwinian medicine contend that pathogens such as flu and the common cold produce symptoms such as coughing, sneezing and diarrhea precisely because these behaviours promote the spread and replication of the pathogen to new hosts through the bodily fluids thereby expelled.

Likewise, rabies causes dogs and other animals to become aggressive and bite, which likewise facilitates the spread of the rabies virus to new hosts.[5]

By analogy, successful religions are typically those that promote behaviours that facilitate their own spread.

Thus, a religion that commands its followers to convert non-believers, persecute apostates, ‘be fruitful and multiply’ and indoctrinate your offspring with their beliefs is, for obvious reasons, likely to spread faster and have greater longevity than a religious doctrine that commands adherents become celibate hermits and that proselytism is a mortal sin.

Thus, Christians are admonished by scripture to save souls and preach the gospel among heathens; while Muslims are, in addition, admonished to wage holy war against infidels and persecute apostates.

These behaviour facilitate the spread of Christianity and Islam just as surely as coughing and sneezing promote the spread of the flu.[6]

Like genes, memes can also be said to mutate, though this occurs not only through random (and not so random) copying errors, but also by deliberate innovation by the human minds they ‘infect’. Memetic mutation, then, is not entirely random.

However, whether this way of looking at cultural evolution is a useful and theoretically or empirically productive way of conceptualizing cultural change remains to be seen.

Certainly, I doubt whether ‘memetics’ will ever be a rigorous science comparable to genetics, as some of the concept’s more enthusiastic champions have sometimes envisaged. Neither, I suspect, did Dawkins ever originally intend or envisage it as such, having seemingly coined the idea as something of an afterthought.

At any rate, one of the main factors governing the ‘infectiousness’ or ‘fitness’ of a given meme, is the extent to which the human mind is receptive to it and the human mind is itself a product of biological evolution.

The basis for understanding human behaviour, even cultural behaviour, is therefore how natural selection has shaped the human mind – in other words evolutionary psychology not memetics.

Thus, humans will surely have evolved resistance to memes that are contrary to their own genetic interests (e.g. celibacy) as a way of avoiding exploitation and manipulation by third-parties.

For more recent discussion of the status of the meme concept (the ‘meme meme’, if you like) see The Meme Machine; Virus of the Mind; The Selfish Meme; and Darwinizing Culture.

Escaping the Tyranny of Selfish Replicators?

Finally, at least in the original, non-‘extended’ editions of the book, Dawkins concludes ‘The Selfish Gene’, with an optimistic literary flourish, emphasizing once again the alleged uniqueness of the “rather aberrant” human species.[7]

Thus, his final paragraph ends:

We are built as gene machines and cultured as meme machines, but we have the power to turn against our creators. We, alone on earth, can rebel against the tyranny of the selfish replicators” (p201).

This makes for a dramatic, and optimistic, conclusion. It is also flattering to anthropocentric notions of human uniqueness, and of free will.

Unfortunately, however, it ignores the fact that the “we” who are supposed to be doing the rebelling are ourselves a product of the same process of natural selection and, indeed, of the same selfish replicators against whom Dawkins calls on us to rebel. Indeed, even the (alleged) desire to revolt is a product of the same process.[8]

Likewise, in the book’s opening paragraphs, Dawkins proposes:

Let us try to teach generosity and altruism, because we are born selfish. Let us understand what our selfish genes are up to, because we may then at least have the chance to upset their designs.” (p3)

However, this ignores, not only that the “us” who are to do the teaching and who ostensibly wish to instil altruism in others are ourselves the product of this same evolutionary process and these same selfish replicators, but also that the subjects whom we are supposed to indoctrinate with altruism are themselves surely programmed by natural selection to be resistant to any indoctrination or manipulation by third-parties to behave in ways that conflict with their own genetic interests.

In short, the problem with Dawkins’ cop-out Hollywood Ending is that, as anthropologist Vincent Sarich is quoted as observing, Dawkins has himself “spent 214 pages telling us why that cannot be true”. (See also Straw Dogs: Thoughts on Humans and Other Animals: which I have reviewed here and here).[9]

The preceding 214 pages, however, remain an exciting, eye-opening and stimulating intellectual journey, even over thirty years after their original publication.

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Endnotes

[1] Mutualism is distinguished from reciprocal altruism by the fact that, in the former, both parties receive an immediate benefit from their cooperation, whereas, in the latter, for one party, the reciprocation is delayed. It is reciprocal altruism that therefore presents the greater problem for evolution, and for evolutionists, because, here, there is the problem policing the agreement – i.e. how is evolution to ensure that the immediate beneficiary does indeed reciprocate, rather than simply receiving the benefit without later returning the favour (a version of the free rider problem). The solution, according to Axelrod, is that, where parties interact repeatedly over time, they come to engage in reciprocal altruism only with other parties with a proven track record of reciprocity, or at least without a proven track record of failing to reciprocate. 

[2] Certainly, many male traits are attractive to women (e.g. height, muscularity). However, these also have obvious functional utility, not least in increasing fighting ability, and hence probably have more to do with male-male competition than female choice. In contrast, many sexually-selected traits are positive hindicaps to their bearers, in all spheres except attracting mates. Indeed, one influential theory of sexual selection claims that it is precisely because they represent a handicap that they serve as an honest indicator of fitness and hence a reliable index of genetic quality.

[3] Thus, Edwin Bowman writes:

As the diameter of the bony pelvis increased over time to permit passage of an infant with a larger cranium, the size of the vaginal canal also became larger” (Bowman 2008).

Similarly, in their controversial book Human Sperm Competition: Copulation, Masturbation and Infidelity, Robin Baker and Mark Bellis persuasively contend:

The dimensions and elasticity of the vagina in mammals are dictated to a large extent by the dimensions of the baby at birth. The large head of the neonatal human baby (384g brain weight compared with only 227g for the gorilla…) has led to the human vagina when fully distended being large, both absolutely and relative to the female body… particularly once the vagina and vestibule have been stretched during the process of giving birth, the vagina never really returning to its nulliparous dimensions” (Human Sperm Competition: p171).

In turn, larger vaginas probably select for larger penises in order to fill the vagina (Bowman 2008).

According to Baker and Bellis, this is because the human penis functions as a suction piston, functioning to remove the sperm deposited by rival males, as a form of sperm competition, a theory that actually has some experimental support (Gallup et al 2003; Gallup and Burch 2004; Goetz et al 2005; see also Why is the Penis Shaped Like That).

Thus, according to this view:

In order to distend the vagina sufficiently to act as a suction piston, the penis needs to be a suitable size [and] the relatively large size… and distendibility of the human vagina (especially after giving birth) thus imposes selection, via sperm competition, for a relatively large penis” (Human Sperm Competition: p171).

However, even in the absence of sperm competition, Alan Dixson observes:

In primates and other mammals the length of the erect penis and vaginal length tend to evolve in tandem. Whether or not sperm competition occurs, it is necessary for males to place ejaculates efficiently, so that sperm have the best opportunity to migrate through the cervix and gain access to the higher reaches of the female tract” (Sexual Selection and the Origins of Human Mating Systems: p68).

[4] In natural conditions, it is assumed that, in egalitarian societies, where males have roughly equal resource holdings, they will each attract an equal number of wives (i.e. given an equal sex ratio, one wife for each man). However, in highly socially-stratified societies, where there are large differences in resource holdings between men, it is expected that wealthier males will be able to support, and provide for, multiple wives, and will use their greater resource-holdings for this end, so as to maximize their reproductive success (see here). This is a version of the polygyny threshold model (see Kanazawa and Still 1999).

[5] There are also pathogens that affect the behaviour of their hosts in more dramatic ways. For example, one parasite, Toxoplasma gondii, when it infects a mouse, reduces the mouse’s aversion to cat urine, which is theorized to increase the risk of its being eaten by a cat, facilitating the reproductive life-cycle of the pathogen at the expense of that of its host. Similarly, the fungus, ophiocordyceps unilateralis turns ants into so-called zombie ants, who willingly leave the safety of their nests, and climb and lock themselves onto a leaf, again in order to facilitate the life cycle of their parasite at the expense of their own. Another parasite, dicrocoelium dendriticum (aka the lancet liver fluke) also affect the behaviour of ants whom it infects, causing them to climb to the tip of a blade of grass during daylight hours, increasing the chance they will be eaten by cattle or other grazing animals, facilitating the next stage of the parasite’s life-history

[6] In contrast, biologist Richard Alexander in Darwinism and Human Affairs cites the Shakers as an example of the opposite type of religion, namely one that, because of its teachings (namely, strict celibacy) largely died out.

In fact, however, Shakers did not quite entirely disappear. Rather, a small rump community of Shakers the Sabbathday Lake Shaker Village survives to this day, albeit greatly reduced in number and influence. This is presumably because, although the Shakers did not, at least in theory, have children, they did proselytise.

In contrast, any religion which renounced both reproduction and proselytism would presumably never spread beyond its initial founder or founders, and hence never come to the attention of historians, theorists of religion, or anyone else in the first place.

[7]  As noted above, this is among the reasons that ‘The Selfish Gene’ works best, in a purely literary sense, in its original incarnation. Later editions have at least two further chapters tagged on at the end, after this dramatic and optimistic literary flourish.

[8] Dawkins is then here here guilty of a crude dualism. Marxist neuroscientist Steven Rose, in an essay in Alas Poor Darwin (which I have reviewed here and here) has also accused Dawkins of dualism for this same passage, writing:

Such a claim to a Cartesian separation of these authors’ [Dawkins and Steven Pinker] minds from their biological constitution and inheritance seems surprising and incompatible with their claimed materialism” (Alas Poor Darwin: Arguments Against Evolutionary Psychology: p262).

Here, Rose may be right, but he is also a self-contradictory hypocrite, since his own views represent an even cruder form of dualism. Thus, in an earlier book, Not in Our Genes: Biology, Ideology, and Human Nature, co-authored with fellow-Marxists Leon Kamin and Richard Lewontin, Rose and his colleagues wrote, in a critique of sociobiological conceptions of a universal human nature:

Of course there are human universals that are in no sense trivial: humans are bipedal; they have hands that seem to be unique among animals in their capacity for sensitive manipulation and construction of objects; they are capable of speech. The fact that human adults are almost all greater than one meter and less than two meters in height has a profound effect on how they perceive and interact with their environment” (passage extracted in The Study of Human Nature: p314).

Here, it is notable that all the examples “human universal that are in no sense trivial” given by Rose, Lewontin and Kamin are physiological not psychological or behavioural. The implication is clear: yes, our bodies have evolved through a process of natural selection, but our brains and behaviour have somehow been exempt from this process. This of course, is an even cruder form of dualism than that of Dawkins.

As John Tooby and Leda Cosmides observe:

This division of labor is, therefore, popular: Natural scientists deal with the nonhuman world and the “physical” side of human life, while social scientists are the custodians of human minds, human behavior, and, indeed, the entire human mental, moral, political, social, and cultural world. Thus, both social scientists and natural scientists have been enlisted in what has become a common enterprise: the resurrection of a barely disguised and archaic physical/mental, matter/spirit, nature/human dualism, in place of an integrated scientific monism” (The Adapted Mind: Evolutionary Psychology and the Generation of Culture: p49).

A more consistent and thoroughgoing critique of Dawkins dualism is to be found in John Gray’s excellent Straw Dogs (which I have reviewed here and here).

[9] This quotation comes from p176 of Marek Kohn’s The Race Gallery: The Return of Racial Science (London: Vintage, 1996). Unfortunately, Kohn does not give a source for this quotation.

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References

Bowman EA (2008) Why the human penis is larger than in the great apes Archives of Sexual Behavior 37(3): 361.

Clark & Hatfield (1989) Gender differences in receptivity to sexual offers, Journal of Psychology & Human Sexuality, 2:39-53.

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