Mothers and Others

by Sarah Blaffer Hrdy

  For society after society, grandmothers have been shown to influence the reproductive success of kin. For European and North American farming communities where written records were available, the increased lifetime reproductive success of mothers with a grandmother to help could be traced over several generations.73 Birth and death records for 500 Finnish women and 2,400 Canadian women leading hardscrabble peasant lives and destined to lose 40 percent of all infants born to them revealed that if these mothers had their own mother still living in the same community they lost significantly fewer children. In both samples, numbers of surviving grandchildren depended on how much longer the woman herself survived after the birth of her last child. Postreproductive women gained roughly two extra grandchildren for every ten years they survived past completion of their childbearing.74 But these effects were significant only in the case of the first three grandchildren. This suggested that either mothers were gaining valuable experience or else help from older children compensated for the increasing frailty or absence of a grandmother.

  News about hardworking postmenopausal women among the Hadza and the stunning impact of grandmothers on child survival among Mandinka horticulturalists (discussed in Chapter 3) spread fast among anthropologists. Researchers working in highland Peru, Senegal, rural Ethiopia, northeasternmost India, and the deserts of Western Australia began to ask new questions. Others scoured archives in Europe, North America, and Japan. All confirmed the importance of postmenopausal altruists.75 Wherever populations were characterized by high average rates of child mortality, grandmothers—if available—made a difference to child survival.

  Galvanized by the new findings, Rebecca Sear and Ruth Mace set out to review evidence for 28 traditional societies where we already had fairly good demographic information. In all of them, death of the mother in the first two years proved catastrophic, presumably because substitutes for mother’s milk and maternal care were so inadequate. But the lethal impact of losing one’s mother decreased with the child’s age, and in five societies a motherless child who survived to age two had as good a chance of reaching adulthood as a child whose mother had not died. Since two-year-olds were still far from independent, other caregivers had to be stepping in. And no single class of caregivers made a bigger difference than grandmothers. Their presence was correlated with higher child survival in every one of the twelve societies for which relevant data had been recorded.76

  WHEN AND EXACTLY HOW DO GRANDMOTHERS HELP?

  Overall, grandmothers were turning out to be the most reliably beneficial of all alloparents. Under some ecological conditions, for example in foraging societies when game is short, their presence had an even bigger impact on child survival than the father’s did. At other times grandmothers proved most useful when mothers were young, inexperienced, or lacked older children to help out.77 Children’s age was also a factor since, statistically, children benefited most from having a grandmother present around the age of weaning.78 Whereas some youngsters are nonchalant about the end of nursing and may even wean themselves, more often little monkeys and apes (including human ones) find rejection from the mother’s breast quite stressful. Not only do youngsters lose access to the emotional comfort of sucking there, but they have to compete for available food with larger group members, and may suffer pangs of jealousy if they see a younger sibling nestling where they want to be. It is no wonder that weaning sometimes feels like a death sentence. To some already malnourished and immunologically challenged toddlers, it may actually be one.79

  Recollecting her earliest years, the !Kung woman Nisa recalled how jealous she felt when her newborn brother displaced her at her mother’s breast. Tension between Nisa and her mother erupted whenever he nursed, so what did she do? “I went to the village where mother’s mother lived and told myself I would eat with her. When I arrived at her hut, grandma roasted [food], and I ate and ate and ate. I slept beside her and lived there for a while.” Later, her grandmother returned Nisa to her parents, making a point of scolding her adult daughter in front of Nisa for punishing instead of being nice to her. Nisa was comforted by knowing that she had such an influential ally.80

  Kindly old grannies are a long-standing cultural stereotype. Yet researchers have only begun to zero in on the stress-reducing component of their benevolence. In 2006, seventeen years after he had first gone to Trinidad to find out whether alloparents affected maternal reproductive success, Mark Flinn was still doing research there and published a paper describing the physiological benefits of having supportive alloparents. As predicted, a traumatic social event—such as being threatened or witnessing a fight between parents—led to increases in salivary cortisol levels by anywhere from 100 percent to 2000 percent. But the negative effects of early social trauma (as measured by cortisol levels) was moderated for children with alloparental support, including children with a grandmother on hand.81

  Such demographic circumstances are crucial. The more inexperienced the mother or the fewer older children around to help (her own or perhaps their cousins), the more a grandmother or great-aunt matters.82 Fortuitously, the same high child mortality rates that make grandmaternal contributions so critical also make it likely that postmenopausal women will have few direct descendants vying for their help. Grandmothers can also distribute themselves and channel contributions according to those who need their help the most.83 But demographics aside, it also matters whose mother a grandmother was.

  MOTHER’S MOTHER VS. MOTHER-IN-LAW

  Clearly grandmothers have a range of beneficial effects, even in some cases dramatically reducing child mortality. However, the type of effect she has may vary depending on whether the nearby grandmother happens to be the mother’s mother or the father’s. Across traditional societies, the presence of a maternal grandmother is more likely to be correlated with the enhanced well-being of grandchildren, whereas the presence of the father’s mother is more likely to be correlated with increased maternal fecundity, earlier reproduction, and shorter intervals between birth.84 Such increased maternal fecundity may be a boon for her mate’s reproductive success, but it will not necessarily enhance the well-being of children born in rapid succession and forced to compete for family resources with more siblings. Furthermore, the benevolence of every grandmother is far from guaranteed. Under some circumstances her ministrations prove downright detrimental.

  We need only turn to case studies from some of humanity’s more stratified and highly patriarchal societies to find grandmaternal interventions reminiscent of murderous marmoset and meerkat “grandmothers from hell.” For example, long-standing preferences for particular family configurations in some parts of the world, especially a preference for sons, may result in a paternal grandmother taking the initiative to dispatch an unwanted granddaughter. I am still haunted by a photograph sent to me once by a colleague depicting a pair of brother-sister twins born to a Pakistani mother. The much-desired son, who had remained with his mother to breastfeed, was healthy and robust, while the daughter, who had been taken at birth by the paternal grandmother and bottlefed with a lethal mixture of powdered milk and unboiled water, was limp and emaciated. Shortly after the photograph was taken, the little girl died from chronic diarrhea and malnutrition.85

  Another case of what is better termed a mother-in-law than a grandmother effect can be found in Eckart Voland and Jan Beise’s reconstruction of eighteenth- and nineteenth-century families from Germany’s Krummhörn region. As expected, child survival rates were higher if the postreproductive caregiver was the wife’s mother.86 If the husband’s mother lived in the house, the most salient effect was her daughter-in-law’s shorter intervals between births and higher overall fertility. Although one might expect this higher fertility to result in higher overall reproductive success, it did not. Having a live-in mother-in-law turned out to be correlated with a significantly higher rate of stillbirths and neonatal mortality.87 According to Voland and Beise, these poor outcomes may have been artifacts of pregnant wives living in a dour Calvinist c
ommunity, separated from their own families and under the oppressive and presumably highly stressful surveillance of their husband’s mother.

  Clearly the impact of paternal grandmothers on the survival of grandchildren is not as uniformly beneficial as is that of the maternal grandmother. Several authors attribute reported differences in solicitude to the level of uncertainty that surrounds paternity. If “it is a wise child who knows his own father,” it will take an even wiser, unusually well-informed grandmother to distinguish her son’s child. A paternal grandmother may feel less emotionally committed to grandchildren to whom she might or might not be related.88 It is also possible, of course, that the two women simply do not like each other.

  Whatever the reasons, opposing effects from paternal versus maternal grandmothers similar to those reported for German peasants have also been documented for patrilineal societies in mid-twentieth-century West Africa and eighteenth- to nineteenth-century Quebec.89 Rice-growing peasants from seventeenth- to nineteenth-century Tokugawa Japan also conform to this pattern, albeit with extra twists. It was very unusual in this patrilocal, patrilineal, extremely patriarchal society for a mother to be living with her daughter, but a few did, and the maternal grandmother’s presence was correlated with increased survival rates for both her grandsons and granddaughters. More commonly, it was the father’s mother in the household, and although her presence had no effect on granddaughters, it was detrimental to the survival of grandsons.90 One possibility is that in this rigidly patrilineal system, paternal grandmothers had a stake in reducing the number of heirs competing to inherit the land.91

  Different roles played by grandmothers depend on a range of factors—residence patterns for sure, but also local subsistence conditions, the family’s socioeconomic status, family composition, and inheritance patterns—which will obviously be more important for settled people than among hunter-gatherers who have few possessions.92 Leonetti and her coworkers have undertaken the first study aimed at teasing apart such factors. They are comparing childcare patterns among the mother-centered Khasi community in the northeastern Indian state of Megahalaya with those in a patrilineal and patrilocal Bengali community in the neighboring state of Assam. Among these patriarchal Bengalis, men monitor and seek to control women’s movements, and mothers and their children alike suffer from a lack of direct access to resources.

  Owing to the importance of patrilineally inherited farmland, female chastity is a matter of tremendous concern to Bengalis. Wives are under chronic surveillance, with the father’s mother in her stereotypical role as watchdog, and (as in the case of the eighteenth-century German peasants) her presence is correlated with shorter intervals between births and an overall increase in the number of children born (some women have as many as eleven children). Nevertheless (and this diverges from the German case), the paternal grandmother’s presence is more helpful than harmful in keeping infants alive, even though the fast reproductive pace probably takes a toll on their mothers.93

  In contrast to Bengali mothers, Khasi mothers own property, have considerably more freedom of movement, and benefit from having matrilineal kin nearby. Maternal grandmothers in particular attach high priority to keeping the mother and her children as well-nourished and healthy as possible. Not surprisingly, the grandmother’s labor is positively correlated with how much children weigh, which is on average significantly more than Bengali children of the same ages. Even though the socioeconomic status of the two groups is roughly similar (with no one being that well off), on average Khasi mothers are taller, better nourished, and weigh more than their Bengali counterparts, who by and large are fed less well in childhood and all through adulthood.94 Among 2,666 Khasi infants in this study, those with maternal grandmothers present as opposed to absent were more likely to survive to age ten.95

  Are maternal kin invariably good news then? Not necessarily. Even within matrilocal societies, growing population density can increase competition between kin for matrilineally inherited resources. This appears to be the case in parts of contemporary Malawi, where having the mother’s mother or sisters around actually proves detrimental to child survival. In the case of Malawi, I suspect that this situation is due to the decreasing availability of farmland women need to support their families. In the terminology of Sherman’s eusocial continuum, such competition increases the degree of reproductive skew, since mothers with access to more land can rear more young. This speculation is consistent with the fact that the correlation between nearby matrilineal kin and child mortality was confined to girls and most pronounced in families that had heritable land.96 This 2008 study from Malawi is important, reminding us how much we still have to learn about humans as cooperative breeders.

  PATRIARCHAL COMPLICATIONS SINCE THE PLEISTOCENE

  Patrilineal concerns are one reason why the impact of the husband’s mother on the well-being of grandchildren can be so variable. Universally, people in traditional societies want children, but residence patterns, family compositions, values, and priorities regarding children differ. Whereas people with matrilineal/matrilocal histories award high priority to maternal interests, those in patrilineal, and especially full-fledged patriarchal, societies where property is passed from fathers to sons are more concerned with ensuring the husband’s paternity and preserving patrilineal access to resources, even when this entails practices detrimental to the well-being of mothers (and children too), such as sequestering women or sewing up their vaginas (infibulation).

  Through time, a fixation with chastity can take on a symbolic and institutional life of its own, so that tremendous mental energy and effort gets channeled into policing and controlling female sexuality and convincing women that it is essential for their own and their children’s sake to be “good” (that is, chaste, dutiful, submissive, and self-sacrificing) mothers.97 It’s not that men and their mothers in these societies don’t care about children. They do, often desiring lots of them, especially several sons (an heir plus a spare). But preservation of the patriline and patrilineal institutions still takes priority, even to the point of depriving children of grandmothers. Consider the once widely practiced South Asian custom of suttee. When a man died, it was his widow’s “sacred duty” to burn herself alive. Her suicide forestalled diversion of resources for her continued support as well as eliminating risks that she might dishonor the patriline by taking up with another man. However, suttee was not just hard on virtuous widows. It deprived dependent children of grandmothers and great-aunts, as well as mothers.98

  WHAT ABOUT GRAMPS?

  Even among foragers like the Efe, where lots of hands-on male care can be found, grandfathers spend surprisingly little time holding babies. Fathers, cousins, and older brothers spend more than twice as long babysitting as grandfathers do (also more than five times more than uncles). Among the Hadza, grandfathers are far less likely than grandmothers to even be in the same camps as their grandchildren. In Sear and Mace’s 2008 overview, the proximity of grandfathers had little detectable impact on the survival of their grandchildren.99 Does this mean grandfathers don’t matter?

  Certainly as they age, most men continue to be interested in what happens to their descendants. In patrilineal societies, older men take a special (if not particularly hands-on) interest in sons and grandsons, while in matrilineal societies uncles (mother’s brothers) are especially important mentors. In societies like our own, where intergenerational transmission of property is both very important and unusually well-documented, men go to more trouble than women do to channel wealth down the generations to blood descendants, to keep property “in the family.”100 In hunter-gatherer societies, property does not have anything like the same importance, but social relationships are no less complex—or prone to generate discord. Respected middle-aged and older men, aging fathers, grandfathers, and uncles help relatives broker disputes between rivals or co-wives, increase the likelihood that groups retain the use of waterholes, and perhaps most importantly help arrange suitable matches and influence group rec
ruitment and retention.

  As Polly Wiessner has shown for the !Kung, the combined hunting, healing, and political skills of “elder statesmen” diffuse tensions, promote solidarity, attract useful group members, and otherwise promote the group’s solidarity and continued access to resources. The impact of a respected man can persist long after he passes his prime. In a follow-up study tracing the fates of different Bushmen families, Wiessner found that a man skilled in setting up long-term hxaro relationships and in other ways could keep his group together in the same area almost twice as long as less-gifted elders could. As she put it, “Thirty-four years later, the wives of men who excelled in these activities had an 84% chance of living with their mature, married children as opposed to the 34% chance of women married to less skilled men.”101 Whether or not old men continue to reproduce themselves, or even whether or not they are actually the progenitors of children born to younger wives, such elder statesmen have kin in the groups whose long-term interests they promote.102 Such men are not so much uninterested in children as they are uninvolved in childcare.

  There are few primate analogues for the stabilizing influence of postprime men. With physical decline, nonhuman primate males tend to become marginalized or are driven out of the group altogether. The closest parallel might be a silverback male gorilla accompanied by a younger black-backed male apprentice in his same group. Even after the older male has passed his prime, the silverback continues to play a protective role, and the presence of multiple males in the group increases infant survival.103