swings in “emotional tonus,” were not only presumed unfit for the hunt, but to pose a disruptive influence by stimulating male competition for sex. On this basis, the theory concluded that natural selection has favored females who acquiesce to their basic reproductive and domestic roles.
A new chapter on theories of human social origins was introduced in 1975 with the publication of E. O. Wilson’s Sociobiology. The sociobiology movement spurred significant new scientific research that has led to a re-examination of assumptions about the evolutionary consequences of human anisogamy. Unanimity of opinion among its followers, however, has been elusive.6 One sociobiological perspective, exemplified by the selfish-gene theory, is that the disparate reproductive strategies of the sexes are inherently conflicting and are played out in an atmosphere of male self-interest, parasitism, and deceit. Other sociobiological theories, in contrast, recognize differences in male-female reproductive strategies but seek to understand how the fitness of both sexes and that of group members is facilitated through the evolution of social behaviors based on cooperative, reciprocal relationships. These contrasting viewpoints are briefly outlined here, and their relevance for theories on human family origins are explored more fully in the next two chapters.
Exploitation and Parasitism
Perhaps the most well-known work linking anisogamy to male social dominance is Dawkins’s The Selfish Gene (1976). It advances the notion that genes tailor their replication strategies to fit the bodies in which they find themselves and that these opportunities differ for male and female bodies. For Dawkins, it all comes down to anisogamy—all social differences between the sexes can be traced to the fact that sperm cells are smaller and more numerous than eggs:
Sperms and eggs . . . contribute equal numbers of genes, but eggs contribute far more in the way of food reserves: indeed, sperms make no contribution at all and are simply concerned with transporting their genes as fast as possible to an egg. At the moment of conception, therefore, the father has invested less than his fair share (i.e. 50 percent) of resources in the offspring. Since each sperm is so tiny, a male can afford to make many millions of them every day. This means that he is potentially able to beget a very large number of children in a very short period of time, using different females. This therefore places a limit on the number of children a female can have, but the number of children a male can have is virtually unlimited. Female exploitation begins here. (Dawkins 1976: 141–42, emphasis added)
The theory is that each reproductive partner has the goal of maximizing the number of their surviving offspring, but that females are at a disadvantage due to their greater parental investment. According to Dawkins, two principal “counter-ploys” may be pursued by females to reduce their exploitation by males. The first, dubbed the “domestic-bliss” strategy, envisions females as feigning “coyness” in order to assess potential mates in advance for favorable attributes (i.e., fidelity and domestic assistance) and to demand material investments prior to copulation. The second is referred to as the “he-man” strategy, where females, in lieu of securing parental assistance for their offspring, settle for trying to select mates that appear to have “good genes.”
These strategies notwithstanding, Dawkins’s scheme offers females little hope for escape from exploitation by promiscuous males, who are portrayed as naturally self-serving, devious, and irresponsible. Saddled as such with their “egg yokes,” females are equipped with few liberating tools beyond withholding sexual favors, clandestine entrapment of reluctant progenitors, or luck of the draw.
Figure 1.1. Selfish-gene theory and the origin of female exploitation. By Drew Fagan.
Dawkins’s selfish-gene hypothesis is taken to its logical extreme by van den Berghe (1979), who adopts it as a template for understanding the structure of human social groups, past and present. He proposes that coyness and slower erotic arousal have evolved as female strategies to counter male seduction and to ensnare men into monogamous or pair-bonded relationships. Males, in contrast, are naturally promiscuous, and seek to parasitize women for their reproductive potential. Male dominance, patrilineal descent groups, and polygyny are seen as natural outcomes of the desire of men to secure the reproductive power of women, assure paternity, increase the number of offspring, and maximize their inclusive fitness by passing property on to their sons. Matrilineal social groups, while recognized, are viewed as rare and aberrant, arising where paternity is made less certain by a high incidence of adultery, divorce, and the “cuckolding” of absentee males. In these situations, it is argued, parasitism by males is simply transferred to their brothers-in-law for the benefit of their uterine nephews, with whom they share genes through their sisters. According to van den Berghe (1979: 108): “In both types of society, women are dominated by men who set norms in an attempt to control women’s reproductive behavior for maximum male fitness.”
The picture that emerges from such selfish-gene models, then, is that anisogamy has preprogrammed the sexes for asymmetrical and parasitic reproductive roles in the evolutionary drama. Males are typecast as the sexual protagonists and females as the reticent objects of their exploitation. Similar conclusions on the proclivities and copulatory appetites of the sexes were reached by Daly and Wilson (1978) and by Symons (1979).7
Such theories generated immediate controversy and academic debate within the field of evolutionary biology. Is our species the product of a grand genomic zero-sum game? Were the selective pressures that favored cooperative behaviors and encephalization in evolving hominins exerted largely on males? Are female primates naturally passive, noncompetitive, and asexual? Continuing research over the ensuing decades has shed new light on these questions, and has challenged previous notions about both human sexuality and human societal origins.
Complementarity and Cooperation
An alternative perspective on the social consequences of anisogamy is that selective pressures favored the evolution of disparate but complementary behaviors among the sexes within the context of cooperative breeding communities. This theoretical framework assumes that both males and females are active players, each pursuing their reproductive strategies sexually, politically, and economically, and further, that their mutual reproductive success is enhanced by the creation of collaborative and overlapping alliances.
By the mid 1970s, androcentric theories on human societal origins were being increasingly challenged by the women’s movement, and female scholars began to re-examine prevailing assumptions in the fields of anthropology and primatology.8 Sarah Hrdy, in her seminal work The Woman That Never Evolved (1981), questioned the notion that natural selection had exerted its influence primarily or exclusively on males. The book presented data that challenged existing stereotypes of primate behaviors, which had previously relied largely on observations of male dominance hierarchies and differential male access to estrus females. Women primatologists took to the field, placing primary research emphasis for the first time on the sexual and social lives of females. The results of these studies literally transformed our understanding of primate breeding systems (Small 1984, 1993).
What researchers discovered is that female primates are far from the coy, asexual, demure, and parasitized creatures some portrayed them to be. Instead, they are often sexually aggressive, actively seeking the novelty and variety of multiple partners while utilizing sex to create strategic alliances that further their reproductive success. Females are also often highly competitive, commonly organizing themselves into stable hierarchies in which status and territories are passed from mother to daughter. These hierarchies may impact access to food resources and, because they have greater stability and permanence than male mating hierarchies, can play a critical role determining the overall social structure of the group. In short, female primates are deliberate and active participants in the game of reproductive success. The strategies of males and females
