Mothers and Others

by Sarah Blaffer Hrdy

  According to this logic, males with bigger brains would have been more successful hunters, better providers, and more able to obtain mates and thereby pass their genes to children whose survival was under-written by a better diet. Meat would subsidize the long childhoods needed to develop larger brains, leading eventually to the expansion of brains from the size of an australopithecine’s to the size of Darwin’s own. Thus did the “hunting hypothesis” morph into one of the most long-lasting and influential models in anthropology.12 Subsequent versions wove together increasingly coherent scenarios in which early human evolution was a “direct consequence of brain expansion and material culture” fueled by an increasingly bipedal, increasingly effective hunter. Big brains, and with them superior intelligence, were viewed as “the sine qua non of human origin.”13

  At the heart of the model lay a pact between a hunter who provided for his mate and a mate who repaid him with sexual fidelity so the provider could be certain that children he invested in carried at least half of his genes. This “sex contract” assumed pride of place as the “prodigious adaptation central to the success of early hominids.”14

  Over time, minor alterations have been made to accommodate new findings such as the importance of vegetable foods in the diets of African foragers. As it became apparent that among some foragers (like the !Kung) plant foods accounted for slightly more calories than meat, researchers started paying more attention to female contributions.15 In the wake of revived theoretical interest in Darwin’s ideas about female mate choice, and with the realization of just how much variation there was in the lifetime reproductive success of one mother relative to another, scientists also started paying more attention to the reproductive strategizing of females. Nevertheless, after a century and a half, the central assumptions underlying the hunting hypothesis still persist.

  WHEN THE SEX CONTRACT FALLS SHORT

  The following extract from a 2004 textbook (the two authors happen to be at Harvard, where the hunting hypothesis has long been a centerpiece of the teaching curriculum) is typical. They take for granted that “monogamous pair-bonding and nuclear families were dominant throughout human history in hunter-gatherer societies” and go on to argue that the “most straightforward explanation of the trend toward monogamy is that smart female hominids went to work on chimpanzee-like hominid-males and—step by step, mate selection by mate selection—shaped them up into loving husbands and fathers with true family values” by choosing the cleverest hunters best able to support their wives and children.16

  No mention is made of what happens when this “loving father” fails to adequately provide because all the eland have migrated elsewhere, or because he had bad luck or poor aim that day, or because he got himself killed or took up with an additional woman, leaving his mate and her progeny with a smaller share, or left them altogether. There is no mention of help from any other quarter, because it has been so long assumed that we knew who provided what to whom. According to a 2003 article in Newsweek, “Since the beginning of time . . . women have been programmed to seek a mate who can provide for a family.”17 This ancient heritage supposedly explains why women today remain perpetually on the prowl for wealthy men.18

  However, a new breed of paleoanthropologists, trained to decipher fossils and stone tools but also to study the subsistence strategies of living hunter-gatherers, were less convinced. They were aware how extremely egalitarian hunter-gatherers tend to be. It made no sense to project onto such people the within-group wealth differentials typical of more stratified societies.

  More to the point, these ecologically-minded fieldworkers asked how a Pliocene-Pleistocene hunter would be able to provision his mate and her offspring, assuming he wanted to. New and better evidence on how African Homo erectus actually obtained meat, along with more realistic assessments of how rarely even the best contemporary hunters succeed in killing big game (perhaps once or twice a month), challenged underlying assumptions of the model. Newly available quantitative information on the highly communal way foragers share with the whole group made it clear that the most successful hunter would often get no more for his family than the most hapless did. Criticisms of the hunting hypothesis, simmering for more than a century, came to a head.19 By the end of the twentieth century, as James O’Connell, one of this new breed of behavioral ecologist/archaeologist, put it, the hunting hypothesis had “effectively collapsed.”20

  Like all young primates, H. ergaster [that is, the African branch of Homo erectus] juveniles probably had to eat several times a day, every day. Like modern children, they probably relied on others to provide most of their food for years after weaning. The hunting hypothesis holds that early human males were the main source of this support, yet traditional East African hunters living in similar habitats today cannot meet this need, despite their use of sophisticated weapons. Though meat represents a sizable fraction of their families’ annual caloric intake, it is not acquired reliably enough to satisfy the daily nutritional needs of their children.21

  Hundreds of thousands of years after Homo erectus, men hunting in arid African habitats like those occupied by the !Kung—armed with spears, bows, and poisoned arrows—still provide less than half of all calories for their group. Even in game-rich areas like Hadza land in northwest Tanzania, hunters succeed only a fraction of the time, perhaps four of the hundred days they go hunting.22 When hunters do manage to kill a much-sought-after eland or other large ungulate, protein arrives in the form of occasional bonanzas shared by the whole group rather than as predictable meals for the hunter’s wife and children. It is left to women to gather nuts, tubers, and berries or pick up more readily acquired but less prestigious prey like tortoises (arguably mankind’s original “slow food”) in order to reliably provide the next meal.23

  Beyond the difficulty a hunter would have had providing for his family, there was the other problem with the sex-contract model: the likelihood that a man would die, defect, or divert food to additional women. In this respect, the situation among our hunter-gatherer ancestors may not have been that different from what goes on in much of the world today. The needs of children outstrip what most fathers are able or willing to provide. Worldwide, the proportion of households headed by women without men ranges between 10 and 25 percent and is rising.24 In countries such as Botswana, Swaziland, Barbados, Grenada, and elsewhere in the Caribbean, 40 percent of households contain children with no father present. In Zimbabwe, Norway, Germany, and the United States, the proportion is closer to 30 percent. Even where fathers are present, their contributions vary, which is why in countries such as Guatemala, Kenya, and Malawi children in female-headed households may be better nourished than those in families with both genetic parents present.25

  Accurate statistics for men who sire children without knowing or acknowledging it are elusive. What we do know is how often fathers lose contact with their children. In industrialized nations like the United States, close to half of all children whose parents divorce lose contact with their fathers shortly afterward. Within ten years, the proportion rises to two-thirds. For many reasons, not all of which have to do with male priorities, only 52 percent of divorced mothers receive full child support; for children born out of wedlock, the proportion receiving support falls to 32 percent.26 Many men pair with a mate and father a child, hoping to earn a living or planning to stick around, but find themselves unable to. Others start new families with a new wife. Some have no realistic prospect of watching their children grow up (consider Saul Bellow, who fathered a child at age 84). Clearly, caring for all—or any—of the children that he sires is not automatically the top priority of these progenitors. This is why development agencies concerned with child well-being recommend channeling aid directly to mothers, bypassing fathers. That way, money is more likely to be spent on food for the family, medicine, and school fees rather than cigarettes, alcohol, or status symbols to impress peers or other women.27

  Paternal defections are not necessarily recent casualties of capitalist e
conomies, globalization, or postcolonial breakdown in family organization. When Frank Marlowe interviewed Hadza still living by hunting and gathering, he learned that only 36 percent of children had fathers living in their same group.28 A hemisphere away, among Yanomamo tribespeople in remote regions of Venezuela and Brazil, the chance of a 10-year-old child having both a father and a mother still living in the same group was one in three, while the chance that a Central African Aka youngster between the ages of 11 and 15 was living with both natural parents was closer to 58 percent. Pity the Ongee foragers living on the Andaman Islands: none of the 11- to 15-year-olds in that ethnographic sample still lived with either natural parent.29

  Does this mean that fathers are not important? No. However, it does mean that a mother giving birth to slow-maturing, costly young does so without being able to count on help from the father. The impact on child well-being of variable paternal commitment depends on local conditions and on who else is around, able, and willing to help. In some environments, presence of the father is absolutely essential to keep an infant safe or provisioned. In other places, especially if alloparents fill in, disappearance of the father has no detectable impact on child survival. When anthropologists reviewed a sample of fifteen traditional societies, in eight of them the presence or absence of the father had no apparent effect on the survival of children to age five, provided other caregivers in addition to the mother were on hand and in a position to help.30

  WHERE FATHERS MATTER MOST

  Through time and across cultures, among individuals living along the banks of rivers and lakes, in dense forests, or in arid savannas, there has always been variation in what fathers could do to help provision their families. In northern climates and in many areas of South America, most calories came from game. The importance of having a father has been especially well documented for some heavily meat-dependent South American forager-horticulturalists. Many such groups are also characterized by high levels of violence, as was true for the Ache when they still lived exclusively as forest nomads (before they settled near mission stations) and for many twentieth-century groups living in the center of the Yanomamo tribe’s range during much of the twentieth century. When such peoples become “crowded in their landscapes compared to true family-level societies . . . [and] can no longer avoid resource competition simply by moving elsewhere,” anthropologists Allen Johnson and Timothy Earl remind us, the bravest and most aggressive men begin to be regarded as “valuable allies rather than dangerous outcasts.”31 Not surprisingly, being killed by someone else was a main cause of death for children and adults alike.

  Like so many other primates, what mothers and infants most urgently needed a male for was to protect them—not just from predators but from conspecific males.32 Compared with Ache children whose parents remained married, Ache youngsters whose parents divorced had a nearly double death rate. If the father actually died or disappeared altogether, chances of the child dying before his ninth birthday rose three-fold.33 Risks to infants from stepfathers are well-documented, and in the Ache case, survival chances for the fatherless were so compromised that a pregnant woman who found herself widowed (and especially if she expected to remarry) might bury her fatherless child at birth rather than continue to invest in a doomed enterprise.34

  Heavy reliance on meat among foragers like the Cuiva, or again the Ache (who derived a whopping 87 percent of their annual calories from game), put fatherless children at a particular disadvantage.35 As among African foragers, these South Americans have a communal system whereby the best hunter’s share is no bigger than that allocated to the worst. Meat is shared according to a strict “from each according to his means” ethic of “cooperate frequently and share fully.” A participant’s contribution need be no more significant than loaning an arrow or providing information about where game was last seen, but to receive a share a man had to participate. A father who was not around would not be viewed as deserving a share, and neither would his children.36

  As important as fathers can be, providing for children is not necessarily their top priority. Even though Hadza hunters could acquire protein more reliably by targeting small game, such as hares, they preferred hunting for more prestigious but elusive large game.37 Maximizing prestige was a higher priority than maximizing yields. Thus the anthropologist Kristen Hawkes proposed what is now known as the “show-off hypothesis,” according to which big-game hunting is considered more like an athletic sport than a subsistence mode, with men seeking to burnish their reputations in the eyes of other men, and to impress women.

  No one argues that men, or the meat they provide, are unimportant in traditional societies. Indeed, one reason good hunters are so admired is precisely because meat is highly valued and much desired, and with good reason. The more food available, the more fertile women are, potentially enhancing the reproductive opportunities of both sexes as well as the survival chances of better-nourished children. Thus, not surprisingly, when Frank Marlowe analyzed the composition of typical diets across foraging societies, he found a significant correlation between female fertility and how much food was provided by men.38

  The big challenge confronting mothers who give birth to costly young, then, is not that goods and services provided by men are unimportant but rather that women have no reliable way to guarantee paternal support. As one way to hedge their bets and garner alternative sources of support for their children in societies with chronically unpredictable resources or high rates of adult mortality, some mothers manage to line up an “extra” father.

  ADDING EXTRA FATHERS OR PARTS OF FATHERS

  Contrary to the widely held dogma that only men who are certain of their paternity provide for young, in many widely separated corners of the world there exist customs and beliefs that help mothers elicit tolerance, protection, or assistance from men who are only possibly, rather than certainly, related. Among Eskimos, Montagnais-Naskapi, and some other North American Indian tribes, as well as among Central American people like the Siriono and many tribes in Amazonian South America as well as across the ocean in parts of pre- and postcolonial west, central, and east Africa, women are permitted or even encouraged to have sex with real or fictive brothers of their husbands. A range of innovations permits mothers in traditional societies from southwestern China and central Japan, as well as among people like the Lusi of Papua New Guinea and in areas of Polynesia, to line up extra “fathers.”39 Even in times and places renowned for patriarchal family structures, such as the Qing dynasty in China or in traditional India, desperately poor parents sometimes made ends meet by incorporating an extra man (preferably some kind of wage earner) into the marital unit.40

  In an increasingly globalized world where rapidly expanding underclasses are characterized by scarce, unpredictable resources and where men have a hard time earning enough to support a family, and in any event are liable to die young or otherwise disappear, mothers ranging from Africa and the Caribbean to the banlieues of Europe and U.S. inner cities routinely enter into sequential polyandrous (one woman, several men) relationships to make do, hedge bets, or improve their lot.41 The behavior of these women is more accurately described as “assiduously maternal” than “promiscuous.”42 Across large swaths of tribal Amazonia, among forager-horticulturalists like the Bari of Venezuela, the Ache of Paraguay, Wayano of French Guiana, Matis of Peru, Takana of Bolivia, or the Arawete, Kulina, Kuikuru, Mehinaku, or Canela of Brazil, it is socially acceptable, even expected, for a husband to permit real or fictive ceremonial “brothers” to sleep with his wife.43 Even among the Yanomamo, a people famous for their many-wived, polygynous headmen, many women spend at least brief phases of their lives in polyandrous marriages.44 Odds are, a woman’s official husband will be the father of any child she bears. But not necessarily.

  The Yanomamo forager-horticulturalists of South America have become widely known for their fierceness and belligerence, and—in the twentieth century—for raids to steal women and sometimes even for killing children sired by rivals. Yet
on closer examination the temperaments of Yanomamo vary enormously, in part depending on where and among whom they live. Yanomamo living in the lowland forests at the center of this tribal group’s range are indeed characterized by high rates of polygyny and conflict between men over women, resulting in many homicides. But members of the same tribe living in less densely populated highland regions on the outskirts of this core area were relatively peaceful, monogamous, and—according to the anthropologist Napoleon Chagnon—inclined to smile more. In both locales, fathers and maternal uncles were extremely affectionate toward their young relations, as illustrated in this counter-iconic image of a Yanomamo dad delightedly juggling his baby daughter. (I. Eibl-Eibesfeldt/Human Ethology Archives)

  Given what a powerful emotion sexual jealousy is, polyandrous liaisons are a risky strategy, dangerous for all concerned.45 But widely held beliefs about “partible paternity” help ease some of this tension. In these cultures, semen from every man a woman has sex with in the months before her infant is born supposedly contributes to the growth of her fetus, resulting in chimeralike composite young sired by multiple men. Each possible father is subsequently expected to offer gifts of food to the pregnant woman and to help provide for the resulting child.