Hrdy reassures readers in The Langurs of Abu that such behavior is far in our own evolutionary past, and that alpha humans aren’t out to murder other males’ offspring. Human males don’t have to kill a rival male’s baby to win access to and have sex with a woman or to live with her; countless men share a home with a woman and a child or children from previous relationships. “What are the implications of this infanticidal heritage for humans?” she wondered in her book.17 “There is little reliable evidence to support the hypothesis that human males have been selected to murder infants in order to increase their own reproductive success.” Some kinds of culturally sanctioned infanticides do occur, rarely, and usually only if a baby’s chances of survival are small and resources limited, she noted. Among “most preindustrial human societies,” infanticide was “primarily practical,” and often involved the acquiescence or even participation of the mother—which, by the time Hrdy began work on Mother Nature, would be another focus of her research. Infant abandonment or even outright infanticide by a mother is usually linked to “economic constraints, the probability of infant survival and future marriage potentialities,” Hrdy added. In modern times, men of the Yanamamo in Brazil have been witnessed killing children when they raid another community. Mothers may also be kidnapped and their infants left behind, which is “functionally equivalent to infanticide” by males because the children can no longer nurse and are more likely to starve to death, noted Hrdy in The Langurs of Abu. Still, she emphasized in her book, “nothing resembling a genetic imperative for infanticide can be found” among humans. Hrdy does, however, in passing, point to the biblical account of Herod’s order of mass murder to slay male toddlers and babies to eliminate an expected challenge to his rule by the recently born Jesus. Interestingly, she also begins her book referring to the feared murderous jealousy of a Roman ruler in Shakespeare’s Titus Andronicus over his wife’s “blackamoore baby,” clearly fathered by her Moorish lover.18 The mother begs her lover to destroy the baby to save her. He refuses, explaining: “My mistress is my mistress,” but the baby “my self.” If “more primatologists had seen this play before going off into the field, they might better have understood the behavior unfolding before them in the savannas and forests where monkeys are studied,” Hrdy wryly noted.
In 1982 Hrdy, together with zoologist Glenn Hausfater, convened in Cornell a conference of researchers studying infanticide, which resulted in the book, Infanticide: Comparative and Evolutionary Perspectives. Hrdy was confident that the evidence presented would convince any remaining skeptics that infanticide could serve an evolutionary-fitness goal. In the introduction to their book, Hrdy and Hausfater stressed how far science had traveled concerning the view of infanticide in a few short years since Hrdy’s langur study. “Over the past decade, the intellectual pendulum in behavioral biology and related disciplines has swung from an earlier view that infanticide could not possibly represent anything other than abnormal and aberrant behavior to the current view that in many populations, infanticide is a normal and individually adaptive activity,” they wrote.19 In fact, researchers have “begun to interpret an ever expanding list of behaviors as subtle forms of infanticide or counter-strategies to infanticide,” they added. Scientists were initially resistant to the idea of infanticide in the animal world in part because it’s considered such “an abhorrent practice in our own society,” wrote Hrdy and Hausfater. But they also didn’t understand what possible role it could play in survival of the species. “Once infanticide began to be explained in evolutionary terms” by Hrdy, “published reports of infanticide in mammals increased dramatically,” they wrote. The pendulum had swung so far, the authors noted, that “quite possibly, readers ten years from now may take for granted the occurrence of infanticide in various animal species, and may even be unaware of the controversies and occasionally heated debate that have marked the last decade of research on this topic.”
Although the matter was settled as far as most evolutionary biologists were concerned, however, some controversy persisted decades longer within anthropology. There was even a learning curve for Hrdy concerning infanticide among all species, including humans. “From the 1980s onward, there was increasing awareness that infant abuse, neglect, abandonment, and infanticide were far more widespread than even those of us who studied such phenomena had realized,” she wrote in Mother Nature.20 “I already knew that abandonment and infanticide—both in humans and other animals—stretched far back in evolutionary time. I just had not realized the magnitude of what was going on.” Despite the grim statistics, Hrdy is surprised there isn’t even more infanticide among humans. “Given how prevalent infanticide by males is among primates—reported now for over 50 different species, often with much the same pattern as predicted by the ‘sexual selection’ hypothesis I first proposed in 1974—and given how much access to other men’s infants men have in our species, what really surprises me is how uncommon infanticide by males turns out to be in humans,” Hrdy wrote to me in a 2012 e-mail. She attributes that to how “different the breeding systems of humans are compared to those of some of our closest Great Ape relations—gorillas and chimpanzees”—as well as the development of human male emotion and the reproductive strategies of women.
These reproductive strategies became a key focus of Hrdy’s study over the years. She was one of the few women scientists in anthropology when she began her research, and was drawn to an important player in evolution that her male colleagues tended to ignore: females. Most researchers, just as Darwin did, regarded females as passive players in the evolutionary drama unfolding around them. They were viewed generally as sitting by coyly as they were chosen by strong males. Then they did what they were biologically destined to do: have babies and raise them. From this perspective, Hrdy quipped, it was as though females had never really evolved. Yet she had witnessed how intently and strategically females protected their young. Langur females banded together in attempts to shield offspring from murderous new alpha males. This shared protective parenting—which Hrdy later termed “allo-parenting—was cultivated throughout life as female langurs young to old cared for other females’ infants, sometimes within minutes after birth. She also witnessed mothers seeking sex with a range of mates, she surmised, to confuse males about the paternity of their young, which would likely serve as protection since males only attacked infants being carried by females with whom they hadn’t mated.
Human mothers, Hrdy argued, sometimes rely on a similar strategy, by building bonds through sex with more than one interested male, who may then feel protective about her babies, or, at least, view a future when she is carrying their own baby. In such a way, an assertively sexual women can use a man’s uncertainty about paternity to her and her child’s advantage, and, in addition, have available men “at hand” in the event her primary partner deserts her (she may also deliberately seek out a nurturing good provider mate unlikely to desert her, rather than males with the obvious knock-out handsome, strength or intelligence genes). But the breeding tactic “best suited to the goose will often look different from the one preferred by the gander,” added Hrdy.21 The female “many possible fathers” strategy may particularly frustrate a male, who, while he may himself be interested in sex with a number of women, can become obsessed with his partner’s fidelity because he doesn’t want to be caught expending resources on an infant secretly plopped in his nest by a rival male. Because fertilization takes place inside a woman’s body, a male can only know for certain he fathered her child if he has a guard “eunuch at the gate” or a DNA “lab at his disposal,” she notes in Mother Nature.22
Hrdy acknowledged in later books the important parenting role that fathers play, not only in helping to begin life, but also in raising their children. Human males are loving, attentive parents usually in for the long haul. Fathers have powerful biological drives to nurture their young, much like mothers, and react similarly to women in responding to cues like the crying of their babies much like their wives. Yet men tend to res
pond less frequently at a lower threshold of crying. Hrdy argues that tiny differences in parental responsiveness during infancy tend to lead to a significant difference in parent-child relationships over time as a deeper bond develops between a child and the more responsive parent, typically the mother. Still, a man’s continuing presence in a family as his child grows is vitally important to the well-being of a child, from modern America to the Brazilian Ache tribes, where an infant who loses his father is four times more likely to die before the age of two than a cohort with a dad, Hrdy noted in Mother Nature. 23
If Hrdy’s early discovery about parenting among the langurs and their infanticide shocked many, her later findings reassured. Her work underscored how deep the Pleistocene legacy of shared care and provisioning of the young—our evolved parenting as “cooperative breeders”—has shaped our better natures, she has argued in Mothers and Others: The Evolutionary Origin of Mutual Understanding. It is parenting, not gathering together for warfare, that is the elemental force behind our more “other-regarding” and cooperative selves, she maintains. Langurs may murder an infant, but evolutionary eons later, a human infant can melt a man’s heart. Human babies are so dependent for so long that it takes a village to raise them. They could not have survived without a cooperative community of parents along with what she calls “allo mothers” or “allo parents,” people of either sex who help care for the young. Our relative pacifism, our ability to empathize, our capacities to read one another’s intentions, and our eagerness to help and please others were forged while infants were developing to elicit care not just from mothers, but from others as well, Hrdy argues. It’s a life-saving evolutionary legacy that sets humans well apart from other apes. Chimpanzees may be pretty smart, she notes in her chapter “Apes on a Plane,” but if we flew with a planeload of them from New York to Los Angeles, we’d be “lucky to disembark with all 10 fingers and toes still attached.”24 Even among “famously peaceful bonobos, a type of chimpanzee so rare and difficult to access in the wild that most observations come from zoos, veterinarians sometimes have to be called in following altercations to stitch back on a scrotum or a penis,” she notes.
Paleontologist Richard Leakey emphasized the “profound homologies between us and other apes,” while a psychiatrist like Peter Hobson “is more struck by differences between closely related species,” Hrdy noted in Mothers and Others.25 “Both are right.” But from a “tender age and without special training, modern humans identify with the plights of others and, without being asked, volunteer to help and share, even with strangers. In these respects, our line of apes is in a class by itself,” writes Hrdy.26
It was a far different view of interaction among members of a community from what Hrdy had first encountered on Mount Abu. But researchers weren’t done yet exploring darker aspects of our kind of primate.
Canadian research partners Martin Daly and Margo Wilson talked excitedly of Hrdy’s work at a 1976 California seminar while Daly was teaching psychology at the University of California in Riverside. The seminar featured Harvard entomologist Edward O. Wilson’s provocative book, Sociobiology, a tome on the field of study that links social interaction to evolutionary development. Hrdy’s name came up because Wilson cited her langur studies in his book, pointing it out as an example of “routine” infanticide by usurping male animals that served an evolutionary goal. His perspectives and Hrdy’s theory fascinated the academics. They found E. O. Wilson’s and Hrdy’s behavioral interpretations far more convincing than the then-trendy view of what they labeled as social scientists’ “greater good-ism” view of animal societies as designed to preserve and “reproduce the species” rather than a recognition of the powerfully competitive drive within each individual to mate and procreate. Like Hrdy, Daly and Margo Wilson believed animal studies were often contaminated by researcher bias; scientists tended to see what they unconsciously hoped to discover: an altruistic society. Such a society didn’t ring true for them. They were convinced by Hrdy’s theory behind langur infanticide. In light of her analysis, as “horrifying” as animal infanticide appears to the human observer, it is “clearly not pathological,” they would write later in The Truth about Cinderella: A Darwinian View of Parental Love.1 In fact, Hrdy’s insight that langur infanticide served an evolutionary goal “is so compelling that the interesting question is why it was not investigated and understood sooner,” they noted. Hrdy’s proposition that evolutionary “selection will favor infanticidal males over non-infanticidal males” is almost “inescapable,” they concluded.2
Daly and Wilson, however, weren’t as quick as Hrdy was initially in The Langurs of Abu to dismiss her theory’s possible implications for human behavior. Clearly, human males aren’t systematically eliminating their stepchildren as part of a subconscious, instinctive drive toward evolutionary fitness, they acknowledged, but the essence of the evolutionary drive to survive, mate, and successfully raise our own young, who in turn find partners to create families, infuses a significant well of human behavior. Human fathers aren’t langurs or lions, intent on killing a rival’s offspring, but they have been forged by evolution, like langurs, to reproduce and discriminate in favor of their own offspring, which can have significant consequences for stepchildren. “Indiscriminate allocation of parental benefits without regard to cues of actual parentage would be an evolutionary anomaly,” Daly and Wilson noted.3 “Although sexually selected infanticide is clearly not a human adaptation, discriminative parental solicitude just as clearly is.” These “child-specific bonds” make it possible for adults to shoulder and enjoy what the two scientists described as the “onerous burden” of parenthood. Because of the nature of relationships forged by evolution, “step-parents do not, on average, feel the same child-specific love and commitment as genetic parents, and therefore do not reap the same emotional rewards from unreciprocated ‘parental’ investment,” they added. The upshot is that parents would predictably tend to be more careless with or more likely to express anger against a stepchild. Or a husband might be annoyed, even lash out in anger, when a wife seems to favor her child from a previous relationship over his biological offspring.
Given this perspective, and Hrdy’s intriguing findings, Wilson and Daly couldn’t help but wonder about rates of violence in families with stepchildren. As they mulled possible effects among humans, they noted the overwhelming number of stories of evil human stepmothers, and stepfathers, in cross-cultural myths and fairy tales. The “abused stepchild is one of the stock characters of folklore,” they pointed out, with “hundreds of variants” of Cinderella’s plight in a home ruled by an evil stepparent throughout the world.4 A dad under pressure from his new wife, Hansel and Gretel’s stepmom, abandons them in the dangerous woods to be kidnapped and nearly cooked by a witch (who could also represent the stepmother). In the Juniper Tree, a woman beheads her stepson and feeds him in a stew to his father, to protect the family’s assets for her own biological child. In the Indian fairy tale Murimong and Thanian, a brother and sister flee home, sick of ingesting rotting food fed to them by their evil stepmom. The image of an evil stepmother has even infected language. In Dutch, bad treatment by someone may be referred to as steifmoederlijke behandling, or “stepmother treatment.”5 Wilson and Daly theorized that most of the evil stepparent fables focus on stepmothers because moms tend to be the traditional family storytellers, and the tales passed down through generations served as a warning from mother to child about the dangers of a stepparent coming into their lives in the event of their own mother’s death or desertion by a husband. But stepfathers also present as evil doers. A French proverb warns: “The mother of babes who elects to wed has taken their enemy into her bed.”6 Gruesome tales of stepparents “would not persist where their themes had no resonance” with humans, noted the research couple, concluding that they “must have something to do with the human condition.”
Why, they wondered, was there no research into the risks to children posed by stepparents in modern human society in light of
the folklore and especially in the wake of Hrdy’s langur research and further studies by other anthropologists? That oversight, as well as the curiosity Hrdy’s work triggered, convinced the two to veer from their rodent and primate studies to concentrate instead on violence, particularly family violence, this time among the infinitely intriguing populations of Homo sapiens.
When Wilson and Daly began their studies of human violence and homicide, the field was generally dominated by sociologists looking at social impacts, such as poverty, on human actions, or psychologists examining abnormal behavior of perpetrators, noted Daly. The researchers were more concerned with the specific relations between killer and victim, and in possible evolutionary rationales for such violence. Like Hrdy’s research, the stepparent studies they launched rattled the orthodoxy on theories about family violence. In their first major examination of child-abuse rates in stepfamilies compared with intact birth families, Wilson and Daly made a stunning discovery: “Enormous differentials in the risk of violence” turned out to be “a particularly dramatic consequence” of the “predictable difference” in parents’ feelings toward stepchildren.7 In fact, they discovered, having a stepparent turned out to be the single greatest risk factor for severe child maltreatment.8
The scientists’ remarkable findings on violence against stepchildren—revealing rates of abuse of stepkids nearly unimaginably higher than among biological children—sealed their reputations as two of the foremost researchers in evolutionary psychology—a descendant of E. O. Wilson’s sociobiology view of behavior. “Ev Psych,” as its students like to refer to it, involves a through-the-looking-glass vision of us as more apelike and driven by evolutionary pasts than we might like to believe. For all of our vast differences from our ape ancestors, we are also, still, surprisingly similar. We are preoccupied with sex, finding a mate, and raising children. We can watch a Shakespeare play and marvel at the sixteenth-century language, but we’re captivated by plots that deal with “universal” concerns about chastity, fidelity, jealousy, and paternity molded far earlier in our jungle pasts. It’s a convincing vision that, once truly viewed and embraced, is impossible to ever dismiss. It’s not the complete explanation for human behavior, but it provides a key piece of the puzzle, and one that can be used to help shape valid approaches to dealing with lethal violence in a continually evolving humanity.
Killer Dads Page 6
