What I expected from ‘The Myth of Monogamy’ book by David P. Barash and Judith Eve Lipton

As a reader, I was eager to learn about the social-psychological aspects of finding mates, along with a justification from evolutionary biology on why we do what we do. There were several interesting and ‘cute’ accounts of how couples from other species behave very much like us. On the other hand, shocking reports on the prevalence of domestic violence, rape, infanticide were also detailed — so, light-hearted readers are warned.

Something I found problematic is the failure to recognise genders outside of the dichotomy of males and females. Also, the authors have disappointed by purely focusing on heterosexuality and ignoring any other sexual orientations. While they do briefly suggest humans have sex for three major reasons — procreation, relational and recreational — the whole book is focused on the procreational and in minor parts on the relational aspects of mating. Thus the book starts with a strong justification of child-rearing and mate selection behaviour of animals and towards the end fails to connect well on how these reflect on human actions.

For the reference of the reader, extra-pair copulations are abbreviated as EPC. Mentions of male and female mean the whole animal kingdom in general. When referring to the human species solely words such as men and women have been used.

Morality = Monogamy

The authors suggest that our sense of equating monogamy to morality is reflected in the study of animals as well where biologists have presumed monogamy to be the natural form of bonding, but only recently have there been an exodus of research suggesting otherwise. As humans, we believe we are superior to anything else in the world forgetting we are just differently evolved. So the same rules of nature apply to us.

“Out of the 4000 odd mammal species, no more than a few dozen form reliable pair-bonds” (page 11)

Man proposes and woman disposes

It is observed majorly that the females carry, give birth and tend to the offspring, there are exceptions such as sea horses in which the males give birth. That is why the authors draw the distinction between the two sexes by what they contribute biologically to the creation of the offspring — egg or sperm. Any individuals producing eggs are female and those contributing sperms are males.

Production of eggs as is quite known is metabolically expensive compared to sperms — thus the females have limited resources and thus has to invest in productive fertilisation strategies that pay them off evolutionarily by producing high-quality offspring to pass on their genes to subsequent generations. In general, it is observed males have less parental investment and high sexual appetite — because this situation benefits them evolutionarily by enabling passing on a higher number of genes to the next generation. In short, females are concerned about the “quality” of genes passed while males are concerned about “quantity”. This is also one reason why females are more choosey and thus say ‘no’ to sexual requests more often than males.

Mate selection

What does she look for?

Males who are older are more desirable amongst females. Their old age is proof of their good genes, and their previous mating success assures females of their desirability (probably due to popularity bias).

Personal qualities such as the feathers, patches on the throat, symmetry etc. could also attract females by sending a signal of health and thus good genes. There is also evidence suggesting females mated to socially dominant males might not want to engage in EPC (unless they want to deceive a low-ranked ‘sucker’ to assume the children are his and thus provide parental support).

The authors introduce the ‘Sexy Son Hypothesis’ meaning females choose a mate because other females are likely to do so, thus obtaining the advantage to their sons in getting mates which in turn would benefit them in producing more grandchildren (more copies of genes sent to subsequent generations).

The notion of women being “Gold-diggers’’ could stem from an evolutionary fact that women do tend to prefer males with better resources such as better nesting ground. After all, there has also been evidence of females exchanging sex for other resources and males paying material resources for a probability of their genes being passed on through the next generation.

Since females exchange fidelity or at least the appearance of fidelity for the exchange of resources they tend to keep their infidelity a secret. They have more to lose when their partners get to know about their EPC. Firstly there is the threat of domestic violence (observed in many species) whereby the females are subject to physical threat and abuse, a disadvantage provided most females are in general weaker and smaller compared to males (dimorphism is more prominent in polygynous species). Secondly, the threat of abandonment by partners and thus leaving all the parental care in the hands of females.

Females could also agree to certain copulations to protect their offspring. For example, new socially-dominant males of some polygynous primates such as Chimps taking over and replacing the alpha male harem keepers tend to perform infanticide. Such an act enables them to be sure of their paternity to the children; reduce competition to resources and provide only to their offspring, not others. Females have adopted clever strategies such as undergoing a “pseudo-estrus” even while pregnant with another male’s offspring to trick the new alpha male chimp to believe that the child is actually his when it will be born.

What does he expect?

Younger females are preferred by males because of the assurance of their virginity requiring no sperm competition and consequently, confidence that the offspring produced are in fact his if the copulation is successful. As expected this list is quite short as males aren’t as picky as females when it comes to mate selection.

Engagement in EPC

In general females on average engage more in EPC than males. Thus, males have more variable reproductive success compared to females — as there are some men who are more desirable and thus produce more offspring than the average male.

Mate Guarding

Natural selection is a Zero-sum game — success for one means less success for another.

While the authors quote mate guarding behaviour is observed both in males and females, they suggest they employ different strategies. Males could literally stalk, follow their mate and thus prevent interactions and forced sexual advances by other males which could manifest as “love” or “chivalry”. Females could more readily choose and engage in EPC when they are in busy neighbourhoods with suitable males available nearby. Thus males, threatened by the prospect of EPC by their mate, could try to confine them within the couple’s own living space.

Females on the other hand copulate more often and keep the male “busy” as a strategy to exhaust the male’s sperm reservoir and thus reduce EPC or at least successful insemination of another female. Any attention to a female’s mate from other females, make the mated female act all friendly and sexy towards her mate — this they suggest is the female way of ‘mate-guarding’. On discovery of their mate’s EPC partner, they could attack and be aggressive towards the home-wrecking female rather than towards their mate.

Polygyny — most common pattern of mating in nature

Polygyny the authors suggest is more a threat to males than to females. This is because the access to multiple female partners or the ability to maintain a harem is a privilege of only a few affluent, socially dominant males. Thus, males in the middle or lower end of the hierarchy are left without any mates. Meanwhile, the women who are a part of a well-to-do male’s harem are provided well materially — in terms of accommodation, food for herself and her offspring etc. While this could be true, the authors have failed to explore the socio-psychological ill-effects such as powerlessness, vulnerability and objectification of women in these harems.

The imbalance in mate availability in polygyny is also pointed out as one of the major reasons for the failures of hippie spiritual communes with utopian ideologies of open relationships where the leader ultimately has access to all females whereas ordinarily, disciples do not enjoy their disadvantaged position of obtaining mates in the long run.

Sad realities of rape and other sexual assaults (mainly on females by males) across different species are also discussed in depth. They state an example of Mallard Duck where the mate of a female would initially try to attack the rapist after which if not successful he himself would get along to rape the female afterwards to get an upper hand through sperm competition. There are also astonishing accounts of gang rapes and the eventual drowning of female ducks, thus becoming fatal and counter-productive measures of child-rearing. The authors also observe that it’s usually the lower-ranked poor animals in the bottom of the hierarchy in polygynous groups that attempt to rape as it’s their only chance to pass on their genes to the next generation. In this situation, pair-bonding with all its flaws and EPC might still be preferable in reducing sexual aggression, as they ensure almost equal access to mates.

“There is, in fact, a growing body of evidence that human rape, too, tends to be a reproductive tactic of likely “losers”” (Page 54)

The Case for Monogamy

“Essentially only in cases of monogamy males provide any parental care” (page 46)

Birds require assistance from another fellow adult to feed and fend for their offspring. Whereas mammal females in general (though Homo Sapiens are an extreme case where child development occurs spans across years and thus have prolonged childhood and dependency) are much more adept at providing for the offspring by themselves through mammary glands and thus require less assistance from another adult. This could be one reason why birds are much more monogamous (at least socially) than mammals. Shared responsibility of parenting is after all one of the major advantages of social monogamy.

This makes one wonder if this is the reason why romantic couples are sweetly (with social approval and admiration) called “love birds” whereas those who sleep around as said to have had sex like monkeys.

Reasons for the rise of monogamy in Homo Sapiens

Amongst humans, before contact with the west, it is said about 80% of the societies were polygynous. The authors discuss some theories as to why monogamy is so widely enforced in humans. One of them is Fridrich Engels’ theory of the need to pass on ‘private property’ through descendants. Parallelly, the authors propose powerful men in the west gave up on the monopoly of women in exchange for lower-ranking men’s labour which in turn helped the affluent in attaining even better economic status. Another is that monogamy might have evolved as a response to sperm competition. And finally is the womens’ requirement of another stable, reliable adult in raising their children.

Divorce

While infidelity is one of the commonly stated causes of divorce (human or otherwise), the authors suggest that a pair-bond mate searching for an EPC is itself suggesting an impending divorce — that is an unsatisfied mate looking for possible mates after the expected separation from the current partner.

Concluding thoughts

“Although social ideology and legal restrictions cannot change human nature, they can and do impose egalitarianism in several forms” (Page — 138)

The main takeaway of the book is that monogamy amongst humans is the most functional pattern of mating — reducing competition, aggression and providing more or less equal chances for reproductive success. However, EPCs are natural in the sense that they’re embedded within us and would arise even when monogamy is strictly reinforced.