How Humans Became Such Other-Regarding Apes

I am an anthropologist and primate sociobiologist who seeks to understand, step by Darwinian step, how apes could have evolved to imagine and care about what the lives of others might be like.  I believe that such questing for inter-subjective engagement laid the  foundations for significant later developments such as language and cumulative culture. My focus then is on the prequel to what became the main human feature film, worlds with symbols, words and story-telling, realms beginning to be explored by psychologists like Marc Hauser, ethnographers like Polly Wiessner and literary scholars such as Brian Boyd, Joseph Carroll, Jonathan Gottschall and Lisa Zunshine.  What follows is my take on how humans became such “other-regarding” apes.

“Nature red in tooth and claw”, “selfish genes”, and “rational actors” notwithstanding, humans are a peculiarly other-regarding, “pro-social” species. We routinely share and behave in ways that benefit others and find it pleasurable to do so. Our closest relatives among the other apes, chimpanzees and bonobos, with whom we last shared common ancestors some seven million years ago, and still share nearly 99% of  DNA sequences, also descend from highly social, manipulative ancestors and possess similar cognitive capacities, yet they are far more single-mindedly self-serving. In this respect, other apes are far more nearly “rational actors” than humans are.

Time and again, anthropologists have drawn lines in the sand dividing humans from other apes, only to see new discoveries blur those boundaries. By now every one of the Great Apes has been observed to select, prepare and use tools, crafting natural objects into sponges, umbrellas, nutcrackers, even pointed sticks for jabbing prey. Such traditions are transmitted across generations so that researchers in the new sub-discipline of “Primate Archeology” (Haslam et al. 2009) are excavating stone mortars chimpanzees used thousands of years ago.  Other apes are also born able to scan and imitate the faces of their caretakers, much as human newborns do, and they exhibit rudimentary capacities for attributing mental states to others. Chimpanzees and bonobos who exhibit considerable empathy in some contexts, also sometimes help one another (Warneken and Hare 2007) and may  occasionally share food although, in the wild they usually have to be badgered first (Fruth and Hohmann 2002). Apart from language (no one challenges human exceptionalism on this score) remaining outliers  distinguishing humans from nonhuman Great Apes mostly have to do with how much further along the continuum of other-regarding impulses humans fall.

Glossary
Alloparent – Group member other than genetic parent who helps the mother rear offspring (from Greek allo- for other than).
Allomother – Male or female group member other than the mother who helps rear offspring.  This catch-all term can include the genetic father when in the absence of DNA data no one knows who the father is.
Cooperative Breeding – Cooperative breeding refers to species with alloparental care and provisioning of young, and has evolved in roughly 9% of birds and 3% of mammals.  Shared care (without provisioning), as well as cooperative breeding (alloparental care plus provisioning) occurs in many species of monkeys and prosimians, but humans are the only great apes to rear young this way.  Note that “cooperative breeding” does not mean individuals always cooperate; a lot of competition can go on both within and between cooperatively breeding groups. SBH

Humans are far better than other apes at attributing mental states to others and appear to care much more about what others think and feel. Children as young as two years old who have not yet learned to speak are  already concerned about what others think. They are capable of both pride and embarrassment, eager to know how others perceive them. Right from an early age humans are also eager to share with others.    Every human society ever studied is characterized by food-sharing and carefully considered gift-giving. Furthermore, when a human does something nice for someone else, the  brain centers stimulated are those associated with registering  pleasurable sensations.  So what brought about this striving for inter-subjective engagement?

In retrospect, there are obvious benefits to attributing mental states to others and intention-reading.  No other apes coordinate behavior to achieve common goals the way humans do.  But Natural Selection can not favor traits simply because they might be useful and enhance fitness down the line. So how did individuals in the lineage leading to the genus Homo evolve these peculiarly other-regarding impulses? Traits like mutual tolerance, giving impulses and mental attribution had to already be there before higher levels of cooperation,  social learning, teaching, cumulative culture and above all language could develop. Furthermore, as psychiatrist Peter Hobson and  linguists like Tecumseh Fitch and Tom Givón stress,  questing for intersubjective engagement provide important motivations for developing forms of communication that go beyond the signaling of other animals — “watch out”, “there’s danger on the ground” or “food over here”. If even before they master language, children wonder what others think and feel and are capable of inventing  imaginary friends with emotional lives of their own, it is because — as  poet Daphne Merkin  puts it — we humans “long …to find our singular passions reflected in a larger pond than the selves we swim in.”

So just how on  Darwin’s earth did Natural Selection come to favor individuals incrementally better at monitoring the intentions and feelings of others? How did the peculiarly human quest for inter-subjective engagement get started? An important first step is to break down nonhuman-human ape differences into their component parts so as to better understand exactly what traits are involved.

In the most ambitious comparative study to date undertaken at the Max Planck Institute for Evolutionary Anthropology, 106 chimpanzees of all ages, 32 orang utans and 105 two and  a half year old children were subjected to a specially designed  battery of tests allowing Michael Tomasello’s team to compare their sociocognitive capacities (Herrmann et al. 2007). In terms of spatial memory and object permanence, or the ability to discriminate quantities or understand causality, chimps and orangs perform in the same range as human toddlers. The big differences are in the social realm where children test significantly better at learning how to solve a problem from watching a demonstrator. Children are also better at understanding communicative cues like pointing, and better at attributing mental states to others so as to understand what they are intending or trying to accomplish – what psychologists call Theory of Mind.  So to explain nonhuman versus human ape differences, we need to identify selection pressures favoring increases in mutual tolerance, social communication and intention-reading.

To my mind, existing explanations for other-regarding impulses –such as the need for in-group solidarity in the interests of defeating out-group enemies — leave unaddressed these initial steps towards prosociality and fail to explain why other apes such as  chimpanzees did not spend the last seven million years becoming more cooperative as well. This is one reason why in Mothers and Others I focus on one of the most obvious, albeit too often overlooked, differences between humans and other apes, the peculiar way that bipedal apes living in small-scale hunter-gatherer societies rear young.

Among chimps, gorillas, bonobos and orangs, mothers are extraordinarily possessive of new babies, in fur-to-fur, body-to-body contact, not out of touch even for a moment, for the first six months or so of life. Infants are suckled for up to seven years. Once weaned however, nonhuman ape  youngsters  provision themselves. By contrast, human babies born in traditional societies are passed around among other group members from the first day of life, and in some groups are held by allomothers (typically kin — fathers, older sibs, aunts, cousins or  grandmothers) for much of the time, even suckled if the allomother holding them is lactating. Within months, long before children are weaned, infants are fed as well by allomothers who deliver soft or pre-masticated  foods,  kiss-feeding the baby by pushing the mash in with their tongues.  Supplementation of children’s diets continues for many years.

Even though human infants are bigger at birth and take nearly two decades to mature, allomaternal provisioning means that mothers can wean babies sooner than other apes. With toddlers buffered from starvation, mothers breed again sooner, potentially increasing lifetime reproductive success but also forcing mothers to become even more dependent on alloparental assistance. In Mother Nature I proposed that increasingly contingent maternal commitment produced the curious combination of passionate maternal love with ambivalence evident in human mothers.  Although rarely seen in primates with exclusive maternal care, high levels of  ambivalence in mothers short on social support is common in other cooperatively breeding primates. Humankind’s deep legacy of cooperative child-rearing also had implications for the cognitive and emotional development of youngsters growing up dependent upon allomothers (the main focus of Mothers and Others) as well as  implications for allomothers (Burkart et al. in press).

None of us has a machine to go back in time and observe how infants in the Pleistocene were reared. But what we do have is a growing body of information about exactly who cares for immatures not only among other primates, but also among humans  living as hunters and gatherers. Furthermore, it is increasingly clear that in traditional societies with high child mortality, alloparental care and provisioning is not only useful, but critical for child survival. Homo sapiens species could not have evolved without it.

Space does not permit here a review of what sociobiologists are learning about the demographic implications of cooperative breeding and the conditions under which it is likely to evolve — particularly in highly social species with helpless young confronting environmental challenges such as unpredictable resources.  Nor does space permit me to review here information from neuroscience, endocrinology and the emerging field of comparative infant development relevant to understanding what the psychological implications of multiple caretakers were likely to be.  But here are a few of the highlights. The presence of a supportive kinswomen like a grandmother is correlated not only with increased child survival, but also with increased maternal sensitivity to infant needs, and infants growing up with nearby grandmothers are more emotionally secure and develop cognitively at a faster pace. Having older siblings around also enhances development of social skills.  As cognitive psychologists quip, “Theory of Mind is contagious” you catch it from older caretakers. Furthermore, forming attachments to multiple caretakers enhances perspective-taking and conditions children to integrate different perspectives.  Even though historians of the family, social workers and psychologists have long known about cognitive and emotional advantages from growing up in an extended family, only recently have evolutionists begun to recognize that such alloparental assistance would have been essential for our ancestors to rear surviving young.

Now consider information from other primates that cooperatively rear young.  Experiments with tamarin monkeys by Marc Hauser’s team at Harvard, and with marmosets by Judith Burkart and Carel van Schaik at the University of Zurich, reveal that these tiny-brained cooperatively breeding monkeys are far readier to pull a rope delivering food to others than are large-brained chimpanzees in comparable tests. These generous “other-regarding” impulses come into play even if the recipient is  unrelated. In the wild as well, cooperatively breeding tamarins and marmosets tend to be mutually  tolerant  and helpful to one another, as well as unusually good at coordinating their behavior in subsistence tasks.  Among these tiny-brained and distant primate relations, relations, the father (or another male the mother mated with) carries the babies (usually twins) much of the time, except when the mother is nursing them.  Allomothers also provision the babies around the time of weaning such that in some species of tamarins, 90% of the infants’ first solid food comes from alloparents. Chronic food-sharing spills over into generosity in other realms as well. Adults routinely vocalize to call the youngsters’ attention to novel, or particularly palatable, food items while intervening to prevent them from eating toxic foods — behavior that comes close to teaching (Rapaport and Brown 2008; Burkart et al. in press).

In Mothers and Others I summarize such evidence and invite readers to join me in a well-documented thought experiment. Take a primate with the cognitive and manipulative potentials and rudimentary empathy and  Theory of Mind typical of all  Great Apes, and rear that creature in a novel developmental context where his  mother’s commitment is contingent on how much social support she has and she and her infant depend on care and provisioning from multiple caretakers. The resulting phenotype will be a youngster adept at perspective-taking, far more so than any other ape under natural conditions would be. Then subject this novel ape phenotype to novel selection pressures such that infants best at monitoring the mental and emotional states and intentions of others, and also best at learning from them, are going to be those best cared for and best fed. This then leads to directional selection favoring traits like enhanced mutual tolerance, social learning, social communication and perspective taking — precisely the traits that comparisons between humans and other apes require us to explain.

No one knows when cooperative breeding got started in the hominin line. Evolutionary anthropologists Kristen Hawkes and James O’Connell have hypothesized that our ancestors began relying on alloparental care and provisioning by the beginning of the Pleistocene, 1.8 million years ago, and I concur with their reading of the paleontological evidence. If correct, this means that long before behaviorally modern humans capable of symbolic thought, art and language emerged, and even before big brained anatomically modern Homo sapiens with fully sapient 1350 cubic centimeter brains in the last 200,000 years,  these cooperatively breeding ancestors would have been well on their way to  “emotional modernity”. Emotionally modern apes would have grown up keeping track of others and  inordinately interested in the feelings and lives of others, even those out of sight, or far away.

Acknowledgements: This essay is based on a lecture originally presented at the Darwin Festival, University of Cambridge, July 5-9, 2009.

Selected References, including recent additions since Mothers and Others

  • Burkart, J.; E. Fehr; C. Efferson; and C. van Schaik.  2007.  Other-regarding preferences in a nonhuman primate: Common marmosets provision food altruistically. PNAS 104: 19762-66.
  • Burkart, J.; S. Hrdy; and C. van Schaik. 2009 (in press). Cooperative breeding and human cognitive evolution. Evolutionary Anthropology.
  • Fruth, B. and G. Hohmann. 2002.  How bonobos handle hunts and harvests: Why share food?  In Behavioural Diversity in Chimpanzees and Bonobos, edited by C. Boesch, G. Hohmann and L. Marchant. Cambridge: Cambridge University Press, pp. 231-243.
  • Haslam, M. et al. 2009. Primate archeology. Nature 460, 339-344.
  • Hauser, M.; M.K.Chen; F. Chen and E. Chuang. 2003. Give unto others: Genetically unrelated cotton-top tamarins preferentially give food to those who altruistically give food back. Proc. Roy. Soc. London (Series B) 270:2363-70.
  • Hawkes, K.; J.F. O’Connell; N.G. Blurton Jones, et al. 1998 Grandmothering, menopause and the evolution of human life histories.  PNAS 95:1336-39.
  • Herrmann, E.; J. Call; M.V. Hernandez-Lloreda J.; B. Hare and M. Tomasello. 2007 Humans have evolved specialized skills of social cognition: The cultural intelligence hypothesis. Science 317:1360-66.
  • Hrdy, S.B. 1999.  Mother Nature.  New York: Pantheon.
  • Hrdy, S.B. 2005.  Evolutionary context of human development: The cooperative breeding model. In:  Attachment and Bonding, a new synthesis, edited by C.S. Carter et al. Cambridge: M.I.T. Press, pp. 9-32.
  • Rapaport, L.G.  and G.R. Brown   2008. Social influences on foraging behavior in young primates: learning what, where and how to eat.  Evolutionary Anthropology 17: 189-201.
  • Sear, R. and R. Mace. 2008. Who keeps children alive? A review of the effects of kin on child survival.  Evolution and Human Behavior 29:1-18.

25 comments to How Humans Became Such Other-Regarding Apes

  • Daniela Sieff

    UNDERSTANDING OUR EVOLUTIONARY PAST CAN HELP THOSE STRUGGLING WITH CHILDHOOD EMOTIONAL TRAUMA.

    Hrdy’s ideas contribute not only to our understanding of the evolution of human hyper-sociality and intersubjectivity, but they are also extremely relevant to psychotherapy. This is especially so for those who are struggling with the consequences of childhood emotional trauma. When abuse is of a physical or sexual nature, the damage is explicit and thus the cause of the child’s psychological wounding is clear. Hrdy’s work explains why equally profound psychological damage can result from subtle neglect and implicit emotional abuse. In our evolutionary past, in order to raise a human child, a woman needed support from allomothers. If such support was not available, maternal commitment would have been ambivalent — there was little point putting energy into a child who had a poor chance of survival (Hrdy 1999, Hrdy 2009). Thus, for much of our evolutionary history, maternal ambivalence — as expressed though a lack of emotional commitment — would have been literally life-threatening. For our ancestors, an emotionally ambivalent mother would have constituted a danger that was as profound as physical or sexual abuse.

    This understanding has the potential to open the door to healing for many who are suffering from early emotional trauma. In order to heal the psychological damage caused by childhood trauma, the pain has to be validated, but when the trauma has been of an emotional and implicit nature that is hard to do. Worse, carrying pain that we can’t validate leaves us no choice but to act it out through destructive and self-destructive behavior, and to try to blot it out through addictions of various kinds. We become stuck — unable to move beyond the psychological damage.

    Additionally, because there was no apparent abuse, we interpret our anxiety, depression, insecurity, destructive behaviour and self-destructive compulsions to mean that there is something profoundly wrong with us. We cannot understand why we are feeling and behaving as we are, so we conclude that we must be defective as human beings. Such thinking lies at the heart of toxic shame (Kaufman 1980, Bradshaw 1988) — a deep, insidious, non-verbal sense that there is something fundamentally inadequate about who we are, as opposed to guilt which comes from feeling inadequate about what we have done. Toxic shame is psychologically poisonous — we become infected with self-hatred.

    Hrdy’s work helps us to find an antidote to the poison. It enables us to understand that even if we grew up in a materially comfortable home, and were not abused in an explicit way, the emotional ambivalence of our caregivers will have scarred our developing mind (Bowlby 1969, Schore 2003a, 2003b, Siegel 1999, Sieff, 2008, Sieff ms). Hrdy’s thesis helps us to realize that our feelings, moods and behaviors are not proof of our fundamental inadequacy, rather they result from the beliefs and strategies that we developed in order to survive our caregiver’s ambivalence (Sieff 2008). Instead of self-hatred we can begin to develop self-compassion.

    However, if we simply swap the belief that we are victim to our own fundamental inadequacy for the belief that we are victim to our mother’s ambivalence, there can be no healing. So long as we think of ourselves as a victim of any kind we are stuck in a dead-end. Again Hrdy’s work helps — it enables us to move beyond seeing ourselves as victims to our mothers’ ambivalence by encouraging us to develop compassion for our mothers. In the modern world, women rarely have a network of family and community members who can act as allomothers to their children. Although their children survive, they would not have done throughout most of our evolutionary history. Thus mothers without a supportive network are at risk of being ambivalent in their commitment to their children (Hrdy 1999, 2009). When we start to understand these dynamics, we begin to develop compassion for what our mothers (and we) were struggling with.

    In short, compassion for ourselves is necessary if we are to validate our own pain, move beyond toxic shame, and stop seeing ourselves as a victim to our own supposed inadequacy. Similarly, compassion for our caregivers is necessary if we are to move beyond blaming them, and stop seeing ourselves as a victim to them. Both shifts in perspective are needed to bring about the lasting changes in deeply held attitudes and (self) destructive behaviours that constitute psychological healing. When there has been childhood abuse — explicit and/or implicit — achieving these shifts can take many years of painstaking work by both therapist and client. Although a cognitive understanding of the evolutionary underpinnings is not enough in and of itself to instigate these shifts in perspective (Schore 2003a, 2003b, Sieff ms), it does has the potential to make a significant contribution to this process. To this end, Hrdy’s work is profoundly important.

    REFERENCES

    Bowlby, J (1969) Attachment and Loss: Vol 1. New York: Basic Books

    Bradshaw, J.E. (1988) Healing the shame that binds you. Florida: Health Communications, Inc.

    Hrdy, S.B. (1999). Mother Nature. New York: Pantheon.

    Hrdy, S.B. (2009). Mothers and Others. Cambridge, Massachusetts: The Belknap Press of Harvard University Press

    Kaufman, G. (1980). Shame: The Power of Caring. Vermont: Schenkman Books, Inc.

    Schore, A.N. (2003a). Affect Dysregulation and Disorders of the Self. New York: Norton

    Schore, A.N. (2003b). Affect Regulation and Repair of the Self. New York: Norton

    Sieff, D.F. (2008) Unlocking the secrets of the Wounded Psyche – Interview with Donald Kalsched, Psychological Perspectives 51 (2) 190-207

    Sieff, D.F. (ms). On the same wavelength: How our emotional brain is shaped by human relationships. Interview with Allan Schore, to be published in Connecting Conversations: Interviews at the Cutting Edge of Psychological Healing.

    Siegel, D.J. (1999) The Developing Mind: Toward a Neurobiology of Interpersonal Experience. New York: Guilford Press

  • Peter Ellison

    Sarah Hrdy continues her own life-long quest into the roots and antecedents of human nature by joining what is surely one of the most exciting currents in behavioral science today: a final push to understand the origins of human cognition. This has long been the great prize for students of human evolution, the difference that makes all the difference. It is the last of the three Great Questions in science: What is the nature of the physical world? What is the nature of life? What is the nature of mind? Those who are engaged in the pursuit of this final question are beginning to sense that it might be answerable within their lifetimes. If so, the Human Genome Project will pale in comparison.

    Much of the excitement comes from the convergence of research results from diverse fields, including neuroscience, child development, primate and comparative behavior, social psychology, and anthropology among them. At the center of this convergence is what some refer to as Theory of Mind, or the capacity to attribute intention to others. But related to that is a more general capacity to empathize with emotional states and intentional stances through a kind of shadow somatization embedded in special regions of cortex known as mirror neurons. These neurons link areas of the brain that receive sensory inputs related to the observation of action with the areas that are involved in the initiation of the same actions. The individual who observes another yawning actually yawns, too, in this domain of shadow action, sometimes tripping the levers that lead to an actual yawn. But it is also that system by which an infant learns to control the motion of its own limbs, to attend to the gaze of others, and to infer the meaning behind speech. There are doubtless more “parts” to this physical circuitry of intersubjectivity than have been discovered to date, but it already seems that a tremendously rich vein has been opened, perhaps the Mother Lode.

    Enter Hrdy, author of Mothers and Others: The Evolutionary Origins of Mutual Understanding, a book that every participant or observer of the effort to understand human cognition should read. Hrdy’s unique contribution is to argue that novel conditions of rearing, conditions that involve many caretakers beyond the biological mother, may have provided the selective context in which enhanced intersubjectivity originally evolved. All the precursors exist in other apes, especially chimpanzees, Hrdy points out, yet enhanced intersubjectivity may be what set humans on our own particular cognitive trajectory. Having previously, in Mother Nature, argued for the importance of allomothering in humans, to the point of categorizing us as “cooperative breeders” (a special category to students of animal behavior), Hrdy has already prepared the ground for helping us to appreciate the special developmental context for human (and proto-human) infants. She points to a rich body of research that documents the emergence of intersubjectivity in infants as part of the exquisite choreography of interactions between babies and their caretakers. The complexity introduced by multiple caretakers, she argues, provides a particularly intense selective environment for honing intersubjectivity as it develops. It is a powerful, well-supported argument.

    Is there an alternative? I think there is, though I am not sure it is better. The alternative would be that the special selective context in which enhanced intersubjectivity is particularly valuable is not the world of the infant, but the world of the adult. The world in which Hrdy’s proto-humans exist was a world that required new degrees of cooperation, cooperation not limited to reproduction but also including production, the acquisition of resources in an unpredictable environment. Other domains of human physiology indicate selection for enhanced fat storage in both males and females, for foods of increased caloric density, and for protein resources that cannot be efficiently stored in the body. These proto-humans evolved division of labor by age and sex, and depended on each other to a degree far beyond that of their ape relatives. It could be that intersubjectivity pays it dividends in support of the sociality of adults and juveniles. The fact that it emerges in infants is still necessary, and the interaction of the infant with the various members of this productively and reproductively cooperative unit may facilitate that emergence. But multiple caretakers may not be the source of the selective force at work. As Hrdy points out, many species have developed cooperative breeding. But only one ape has developed cooperative production.

    Which came first, the intersubjective adult or the intersubjective infant, may be just as unanswerable as the chicken version. But in this case Hrdy is leading us not just across the road, but to the mouth of the Mother Lode.

  • Tom Givón

    Sarah Hrdy’s stature in primatology, ethology and human evolution has been firmly established with her many publications on comparative primate social behavior, including her classic “Mother Nature” (1999). The current article is a condensation of her new book “Mothers and Others” (2009). Hrdy’s book takes on one of the most vexing core issues in human evolution–the adaptive impetus that led to the evolution of the human capacity for “mind reading” (also called “Theory of Mind” and “inter- subjectivity”). As pertaining to human language, this is our capacity to mentally represent “other minds” during on-going communication.

    Evolutionary primatologists have long come to a near consensus that our “mind-reading” capacity, first ascribed to non-human primates by Premack and Woodruff (1978), is the key to the special evolutionary adaptation of the hominid line, with its big brain, complex problem-solving skills, complex representation of the physical, mental and social world, sophisticated systems of social organization and cooperation, cultural learning–and eventually, language. Till recently, the dominant theories about the evolution of “mind reading” have focused, almost exclusively, on male-oriented social activities such as warfare, aggressive- defensive coalitions and cooperative hunting, what has been called our “Machiavellian Intelligence” (Byrne and Whiten eds. 1988). The problem with this hypothesis, as Hrdy notes, is that it does not explain why our closest relatives, the Chimps, haven’t gone the same evolutionary route as the genus Homo. After all, they are a notoriously Machiavellian–scheming, aggressive/defensive, coalition-building, cooperative-hunting–species (deWaal 1982; Boesch 2005). Hrdy thus poses the key question–why us and not them?

    By collating and comparing the complex evidence on the reproductive and child-rearing behavior and neonate development of social vertebrate and pre-vertebrate species, of social birds and mammals, of social primate, and lastly of extant hunting-and-gathering human societies, and by lining it all up against the hominid archaeological and paleontological record, Hrdy has managed to come up with a unique answer that best fits the diverse multi-disciplinary data: Cooperative Child-Rearing. This uniquely-human arrangement required mothers to read reliably the intentions and emotional disposition of–and then trust their newborn babies to the care of–potential “allo-mothers” (“allo-parents”), be they grandmothers, aunts or nieces, siblings, fathers or other kin and ultimately even benevolent non-kin.

    The complement of the mother’s–and allo-mothers’–behavioral and neurological evolution is, of course, the neuro-behavioral evolution of the human neonates themselves. Born helpless, slow to mature and expensive to maintain, human neonates depend, from the moment of birth, on securing the emotional attachment and nurturing benevolence of potential care-givers, and on learning to accurately assess–and then manipulate–the intentions and emotional dispositions of care-givers, gradually becoming, from an incredibly young age, mind-reading experts.

    Of the many attractive features of Hrdy’s allo-motherhood hypothesis, I will single out but a few. First, by pointing to a selectional pressure that operates during the highly-flexible early stages of developmental (ontogeny), the evolutionary plausibility of the hypothesis is greatly enhanced. The role of behavior as the “pace-maker of evolution” (Mayr 1982), the so-called Baldwin Effect and the process of Genetic Assimilation, is even more plausible in early stages of development, where ontogeny actually partakes in phylogeny (Gould 1977). In this, the contrast between Hrdy’s proposal and the strictly-adult, strictly-male Machiavellian Intelligence hypothesis is indeed striking.

    Second, the focus on mind-reading during early child development makes Hrdy’s work that much more relevant to the evolution of human communication. As her fellow primatologists D. Cheney and R. Seyfarth have noted, “mind reading pervades language” (2007; p. 244). Indeed, the entire Gricean research program in the pragmatics of communication is, transparently, an elaboration of how speakers take account, systematically and rapidly, of their interlocutor’s rapidly-shifting states of intention (deontics) and belief (epistemics) during communication. No real understanding of the adaptive role of
    grammar, to name a key feature, is possible without reference to our mental representation of other minds (Givón, 2005).

    By identifying the likely adaptive impetus for the evolution of the human mind-reading capacity, Sarah Hrdy has, implicitly but unerringly, also put her finger on the core prerequisite for the evolution of human language. It is thus not surprising that her book dovetails so well with the classic 1970′s studies of early child language development, most conspicuously the interactionist work of Sue Ervin-Tripp, Eli Ochs, Liz Bates and Ron Scollon. Hrdy’s findings are, lastly, applicable to a wide range of contemporary social issues: the history and current state of the family, our schooling and child-care practices, and the potential future evolution of Homo sapiens.

    Boesch, C. (2005) “Joint cooperative hunting among wild chimpanzees: Taking natural observations seriously”, Behavior and Brain Science, 28, peer commentary on Tomasello et al. (2005), pp. 692-693

    Byrne, R.W,. and A. Whiten (ed 1988) Machiavellian Intelligence: Social Expertise and the Evolution of Intelligence in Monkeys, Apes and Humans, Oxford: Oxford University Press

    Cheney, D. and R. Seyfarth (2007) Baboon Metaphysics, Chicago: University of Chicago Press

    de Waal, F. (1982) Chimpanzee Politics: Power and Sex among the Apes, London: Unwin/Counterpoint

    Givón, T. (2005) Context as Other Minds: The Pragmatics of Sociality, Cognition and Communication, Amsterdam: J. Benjamins

    Gould, S.J. (1977) Ontogeny and Phylogeny, Cambridge, MA: Harvard University Press

    Hrdy, S. (1999) Mother Nature: A History of Mothers, Infants and Natural Selection, NY: Pantheon

    Hrdy, S. (2009) Mothers and Others: The Evolutionary Origins of Mutual Understanding, Cambridge, MA: Harvard University Press

    Mayr, E. (1982) The Growth of Biological Thought, Cambridge, MA: Harvard University Press

    Premack, D. and G. Woodruff (1978) “Does the chimpanzee have a theory of mind?” Brain and Behavior Science, 1.4

  • Michele Pridmore-Brown

    Sociobiological narratives have often been dismissed as reductionist, as determinist, as Kipling-esque just so stories, and as politically suspect. As deployed by Hrdy in her last couple of books, they are anything but these things. Indeed, she offers a richly nuanced and complex account of how we became “emotionally modern,” as she puts it in her essay here—in other words: how we became individuals who can, to quote Atticus in Harper Lee’s To Kill a Mockingbird, ”climb into [the other’s] skin” and “walk around in it.”

    If competition and rational actor models are at the heart of most straightforward Darwinian narratives, then an intricate politics of sharing and caring is at the heart of Hrdy’s account. To be sure, this politics is viscerally competitive since it is after all about whose genes make it into the next generation. It is also complex, involving feedback loops between an array of ‘feel-good’ hormones like oxytocin; flexible reproductive strategies; and babies and children as active players in the evolutionary game, honed to seduce potential adult caregivers: to in effect create a web of care and resources around themselves. In a sentence: Hrdy suggests that the exigencies of cooperative childcare explains who we are at a fundamental existential level. Notably, the other species of Great Apes are not cooperative breeders (they practice exclusive and unconditional maternal-infant attachment). In humans, by contrast, as Hrdy has convincingly explained (citing a spate of recent research), not only do both mothers and children fare better with multiple others helping, but in most contexts, especially hunter-gatherer ones, infants can only survive to adulthood if ‘alloparents’ are involved in their care.

    As a result, our ancestors—at least in the Plesitocene past– perforce grew up in an ‘intersubjectve soup’ composed of other peoples’ emotions and desires. Reading emotions and interpreting facial and other cues undoubtedly conferred survival advantages, especially when resources were scarce. The more caretakers or allo-parents lined up, whether this included a great-aunt who reliably dug up tubers and shared them or a more capricious uncle or allo-father who sometimes brought meat, the better a child’s chances, and in turn the better-honed her skills became, in an on-going feedback loop. This soup may then account for a child’s ability to identify with others, to keep tabs on who gives under what conditions, but also and more primordially to emotionally bind those others to him- or her-self. In the cooperative breeding context, what Nietzsche dubbed ‘perspectival seeing’ (the power gained from walking around in another’s skin) could well have meant the difference between getting food, care, and other gifts–or the opposite: neglect, which, in most contexts if not the current one, would certainly mean death.

    In terms of literary analysis and gender studies, Hrdy’s paradigm then provides an invaluable lens for understanding oft-subterranean maternal and allo-parental dynamics—and for bringing into the narrative limelight previously neglected actors like children and postmenopausal females. It accounts for maternal ambivalence, as Hrdy has made clear here and in her books. Disenfranchised and isolated mothers are more likely to abandon, or fantasize about abandoning, their young if they perceive insufficient allo-support. ‘Mother love’ is context-dependent. The same mother can be a so-called ‘good’ mother or a ‘bad’ mother at different points in her life-course and under changing circumstances, and she can be a so-called ‘natural’ mother according to the norms of her time while being an ‘unnatural’ one according to the norms of other times or places. Notably, a significant portion of 20th century literary texts have excavated maternal ambivalence: from Kate Chopin and Gilman on to contemporary authors like Munro. Thanks to Hrdy, maternal neglect or abandonment can be read as sometimes tragically strategic rather than just pathological. If anything, applying Hrdy’s insights to texts amplifies the pathos (and vulnerability) inherent in maternity–and also complicates moral judgment. On a related note, Hrdy offers an illustrative insight in her book: behavior that under patriarchy would be called promiscuous can, under a Darwinian lens, be read as assiduously maternal; lining up extra fathers (and maybe obscuring paternity), which is in fact encouraged in certain tribes in West Africa, can confer a survival advantage on progeny if the extras bring gifts of food and babysitting hours.

    As for children themselves, it is no accident that, as I have discussed elsewhere (Times Literary Supplement, May 22, 2009), the winsomeness of famous characters like Pip in Great Expectations or Heidi in the children’s story of that name or the orphan girl in Silas Mariner are crucial to the unfolding of their creators’ plots. That winsomeness is in fact the narrative motor of countless tales—whether it’s the winsomeness inscribed in physical features or of the mind-reading connection-seeking variety or, most often, a combination of the two. Via plumb checks or a lilting voice, or via a talent for raising ‘feel good’ hormones in adults, children drive countless plots. Pip’s winsomeness creates his great expectations. In times of scarcity, Pips and Heidis have an edge over their less winsome peers and siblings, something their literary creators intuitively know. Such characters must therefore be depicted as potent enough, indeed as seductive enough, to single-handedly effect the re-entry of the social outcast into the human fold. Plenty of works of fiction turn on this conceit: the archetypal curmudgeonly male redeemed by the supposedly helpless child, the captor turned nurturer, the convict turned dutiful citizen.

    Indeed, Hrdy’s work is ostensibly about mothers and allo-mothers, but in many ways it is just as much about fathers and allo-fathers. Fathers may or may not be crucial to infant survival, depending on context. Grandmothers and ‘postmenopausal others’ can be far more crucial, especially when men desert, as Hrdy meticulously illustrates. Yet, as the above literary examples suggest, men can also be avid nurturers. This brings me to another fascinating piece of Hrdy’s story—not mentioned in her essay here but deserving emphasis. Endocrinological and other evidence suggests that fathers or potential fathers can be thought of in what I have called Lamarckian terms (TLS, May 22, 2009)—rather than just in Darwinian ones. The potential for nurturing exists in many albeit not all of them (a lot depends on whether they themselves have been exposed to the intersubjective soup as children). Simply being around babies can switch on the nurturing impulse and repeated exposure can amplify its reach (much as is the case in the proverbial Lamarckian giraffe reaching for the leaves and so acquiring an ever-longer neck). In short, recent evidence suggests that men can be physiologically/hormonally altered by being around babies and children —in such a way that may foster their own health or well-being as well as society’s at large. This is certainly a good argument for paternity leave!

  • Darwin is Hobbes read into nature (K. Marx)

    The problem with Sarah Hrdy’s identification of disinterested cooperation – in this essay and throughout her work – as prove of human specialty surfaces already in her first line: “, , and notwithstanding, humans are a peculiarly other-regarding, “pro-social” species” (my underlining). My objection is that it is not “notwithstanding” but because of those “Hobbesian” aspects that humans are pro-social.

    In his 1651 book on the state Thomas Hobbes portrayed humans as nasty, egoistic beings who stick to rules and laws out of well-understood self-interest. Research of the last few decades, including Hrdy’s, has shown that this is false: human interactions are at least as much characterized by sympathy and amity as by Machiavellian enmity. But Hobbes lived long before the Darwinist distinction between proximate explaining (how organisms work) and ultimate explaining (how their evolution has shaped current patterns), germane for Hrdy’s research, became viable. In fact, Hobbes exclusively targets the proximate level of what drives individuals (self-interest) and how social order is constituted (sticking to agreements out of conscious self-interest).

    The proximate-ultimate distinction suggests that altruism is nothing but Hobbesian warre or Darwinian struggle for life, pursued with different means. Or, leaving out confusing metaphors and formulating this as analytical as possible: our evolved human nature is at the basis of our, thus “bounded”, rational choices, which from the perspective of ultimate causality are radically self-serving, however altruistic, empathic, generous or cooperative proximately.

    My worry with Hrdy’s work is that this goes unreflected. Such phrases as “we have evolved to imagine and care”, that as children we “already are concerned about what others think”, that there is a “peculiarly human quest for intersubjective engagement”, and quoting a poet on human longing – all this betrays the presence of a subtext which sits uneasily with her evolutionary analysis. A similar, evolutionarily unorthodox metaphysic feeds into Frans de Waal’s books. Against the view that morality is a cultural overlay hiding a selfish, brutish nature he claims that “deep down we are … truly moral”, (in Primates and Philosophers, p. 6), that our species is “naturally moral” and shows up “genuine kindness” (ibid., 11), that it is a serious “error to think that natural selection as a cruel and pitiless process can only have produced cruel and pitiless creatures” (58; my underlining).

    Such terminology is at odds with the evolutionary paradigm. Seen from this viewpoint, various sorts of altruistic behaviours are not “better” or “worse” than a crocodile’s aggression; both are pathways to selective advantage. Such terminology belongs to another discourse, which deals not with the biology and evolutionary mechanics of what is human but with the ethics and teleology of what is humane. It situates both scientists within a longstanding tradition in anthropological and primatological research of preoccupation with human specialty. This is even more interesting in the case of de Waal because he lays more stress on the continuity between humans and other animals than Hrdy.

    Both authors are therefore not really addressing the Hobbesian-Darwinian challenge to the mainstream Western moral worldview, to wit that nature, including human nature, is not intrinsically anything that can offer comfort or solace, but just Hobbesian warre. That there is no higher sense, no deeper meaning. In terms of David Hume’s famous distinction: no “genuine”, “truly” (de Waals’s terminology) normative ought that would be irreducible to some factual is.

  • Sarah Hrdy replies to Peter Ellison and Daniela Sieff:

    In Mothers and Others I wanted to explain why I thought humankind’s unapelike mode of child-rearing was relevant for understanding why human apes ended up in a different emotional and cognitive realm than did their nonhuman ape relations. For the most part, development has been left out of evolutionary narratives, and one of the challenges I faced was to lay out my argument along with the evidence that supports it without exceeding my word limit. Neither I nor my publishers wanted another blue whale of a book like Mother Nature. Thus, little space was devoted to the myriad factors in addition to cooperative breeding and the developmental context rearing young that way produced. Well might Peter Ellison ask then, as he does in his comment here and also in a long review of the book published elsewhere: what about the grown-ups? “A logical alternative” Ellison hypothesizes, “might be to assume that the selectively relevant aspects of intersubjectivity function primarily in adults supporting protocultural cooperation… and that the developmental emergence of intersubjectivity in infancy is simply the necessary ontological progression.” (2009: 447). Surely if natural selection was favoring infants good at monitoring their caretakers and eliciting nurture, alloparents as well must have been selected to discriminate between conflicting demands, to become more mutually tolerant and to coordinate care with others, to learn from others and even become motivated to teach others– topics already being developed by Judith Burkart, Carel van Schaik and others. But which came first — the clucking chickens or the riveting sound of pecking from inside the egg? I don’t know the answer, but comparative evidence ranging from the effects produced by larval begging on provisioning hive-mates in primitively eusocial insects to the Disney-exploited impact of infantile sex appeal in our own species, tempt me to put my money on the “sensory trap” produced by immatures who may be as close to “prime movers” as we are likely to get, even though neither needy infants nor their nurturers ever either develop or evolve in a vacuum.
    Peter also suggests that we keep in mind a proto-human world where new degrees of cooperation emerge for “the acquisition of resources in an unpredictable environment”. Indeed, we should. Mothers and Others includes brief sections on “The Critical Importance of Sharing Food” (pp. 180ff) and on the “Ecological Factors in the Evolution of Cooperative Breeding” (pp. 197ff. ) which mention the importance of “special environmental challenges such as unpredictable rainfall or fluctuating food availability which would make it especially hard to stay fed or keep young provisioned.” But Peter is right, I should have stressed these more. If I had it to do over, I would include more about the chronic climatic changes characterizing Africa all through the Pleistocene (Potts 1996). Peter Ellison has to be right that the “pooled energy budgets” we find in the human line (Reiches et al. 2009) did not arise by accident. I really should have said more about this even though I would only have been paraphrasing what Potts, Boyd, Richerson and others have already said so well about the role that fluctuating climates played in the emergence of the cognitive attributes of our problem-solving, culture-transmitting species, and I would only be recapitualting the painfully evident irony of a species now threatened by the very class of forces that helped to forge it.

    Everyone reading the “On the Human” essays, is I suspect already committed to the value of interdisciplinary perspectives. But in his long review, Peter Ellison (2009) goes a step further, reminding us of the value of including among these multiple perspectives insights gained from psychoanalysis, a perspective evolutionists are not ordinarily inclined to consider. I agree. For that reason I feel particularly fortunate to have a reader like Daniela Sieff who has thought deeply about the interface between evolutionary and psychoanalytical perspectives — especially in the realm of child development. Daniela displays such an unnerving knack for reading between the lines and for succinctly and insightfully articulating links between my theorizing and advice that might actually be useful to someone that I have nothing to add except that I would like to read more of what she has to say.

    Ellison, Peter. 2009. A growing thought. Evolutionary Psychology 7(3): 442-448. (http://www.epjournal.net/filestore/ep07442448.pdf)

    Potts, Rick. 1996. Humanity’s Descent: The consequences of ecological stability. New York: Avon Books.

    Reiches, M.W. ; P.T. Ellison; S.F. Lipson; K.C. Sharrock; E. Gardiner; and L.G. Duncan. Pooled energy budget and human life history. American Journal of Human Biology 21:421-29.

  • Please see combined reply to Daniela Sieff and Peter Ellison below.

  • Comment by Elizabeth Marshall Thomas

    I found Sarah Hrdy’s essay fascinating. Not being an anthropologist in any real sense (it’s just that if you write about people other than your own you get called an anthropologist) I’m not sure I’m qualified to comment, but I would like to add an observation about the social nature of our species, an observation made years ago (1950s) when with my parents, Laurence and Lorna Marshall, and my brother, John Marshall, I lived among Ju/wa Bushmen in the Kalahari interior, when these people lived in the Old Way, solely from the savannah by hunting and gathering. Our work is and was occasionally criticized for portraying the Ju/wasi in roseate terms for their ability to cooperate and avoid conflict, yet our account was accurate and this is why. Judging from archaeological research showing modern Ju/wa encampments by seasonal lakes that had been inhabited continuously for about 35,000 years and perhaps much longer, with virtually no change in the material culture, the present inhabitants presumably were still living very much as our ancestors lived when, 150,000 years ago, we became human beings amind the rest of the African savannah fauna. This would imply a continuity in the Ju/wa social arrangements as well, if only because the requirements for them were the same as for all creatures who belong to the natural world, with water and a food supply determining such things as group size and territoriality. In the case of the Ju/wasi, who for many reasons are often called the First People, cooperation and sharing were essential, as was good will, to the point that the entire culture was focused upon honing these behaviors. To be sure, the social excellence of the Ju/wasi was in certain instances limited to their own kind, so that non-Ju/wasi were not always considered to be fully human (animals without hooves, bad people, etc.) hence conflicts with non-Ju/wasi would have occurred, but within the group, dozens of social mechanisms–far too many to list here–were in place to promote social harmony. Among the most important of these was an elaborate kinship system as described by Lorna Marshall, and another was the gift-exchanging system known as haro, described so perfectly by Polly Wiessner, in which people exchanged gifts with their haro partners, often traveling great distances to do so. In survival terms, the payoff for such social mechanisms was large. For instance, if you were on good terms with distant people who controlled water sources and food producing areas other than your own, those people could be counted upon to welcome you when your own water source or food supply failed. In such a situation, it is better to be loved, or at least well-liked, rather than merely tolerated. Another important payoff for the Ju/wa survival mechanisms was, in my view, that people lived longer. Not only did the adults feed and protect the children and each other, they fed and protected the older people too, even though the elders were no longer reproductive or contributing to the food supply. The survival value in keeping the elderly was that they remembered things from long ago. In the event of a fifty year drought, for instance, the people who were sixty and older would remember how their families had dealt with the problem and thus might have useful advice. (We are not the only animals to have discovered this.)
    Personal behavior was also important, again to insure cohesion. Modesty was essential–no one wanted to stand out above the rest for fear of inspiring jealousy. Arguements were usually resolved by group consensus, fighting among group members was considered extremely dangerous and was avoided at all costs. Sharing was also essential. Lorna Marshall wrote, for instance, that the Ju/wasi seemed to want to erase every suggestion that the meat resulting from a successful hunt belonged to the hunter. Because of this, many different people had the potential of “owning” an important food even though they had no part in acquiring it, and over time (because even the Ju/wasi had favorites) the practice ensured that the distribution of important foods acquired by strong adults was equitable.
    The ideal group had people of all ages, not too many to be fed by one important game animal, not so many as to challenge the local slow game and plant food populations, but not so few that the group could not discourage predators, and there were predators–leopards being the worst–all of whom could prey successfully on solitary people or small groups. Thus it was important for groups to be cohesive, and for an individual to have recourse to other groups if for any reason his or her cohesion failed. The most terrible thing, in the eyes of the Ju/wasi, was to be all alone. “It is bad to die,” one woman told my mother, “because when you die you are all alone.” That we as human beings have mechanisms such as sensitivity and empathy to promote cohesion shows, I think, what was required of us to survive, often as the only primates, on an essentially dry, bushland savannah, without much water and no tall trees to climb at night, for our first 150,000 years.
    By now, most human cultures have abandoned much of the social excellence of the First People, as we Americans now demonstrate on a daily basis, especially in our current political behavior. Suffice it to say that the Rush Limbaughs and Sarah Palins among us would, in the deep past, have been fed to the hyenas.

    Elizabeth Marshall Thomas wrote “The Harmless People,” (1959) and “The Old Way: A Story of the First People” (2007). Lorna Marshall wrote “The!Kung of Nyae Nyae” (1976) and “Nyae Nyae !Kung Beliefs and Rites” (1999).

  • Sarah Hrdy

    Mothers and Others stops short of discussing how and why language evolves, so the linguist Tom Givón’s comments and the literatures he cites add a valuable dimension. In the absence of intersubjective engagement, why bother to take vocal communication so much further than other creatures do? Most of us can agree on that. But then what? I agree with Tom about the key role played by “genetic assimilation” and The Baldwin Effect. Lucid discussions of this process can be found in the opening chapter of Tom’s 2009 book on The Genesis of Syntactic Complexity: Diachrony, ontogeny and neuro-cognition as well as in relevant portions of Mary Jane West-Eberhard’s monumental 2003 book Developmental Plasticity and Evolution. As signaled by the epigraph to Mothers and Others, little in my book makes sense except in the light of the theoretical perspective she lays out.

    Givón also highlights something which although widely recognized and perhaps even over-stated in the humanities is just as widely soft-pedaled or overlooked entirely in evolutionary circles. That is the extent to which prevailing theories about Machiavellian Intelligence and the evolution of mind-reading “have focused, almost exclusively, on male-oriented social activities such as warfare, aggressive-defensive coalitions, and cooperative hunting…” Over the years, many of my critics, especially those from Evolutionary Psychology, found it convenient to identify me with that most dreaded F-word, Feminism, and so dismiss my arguments on a range of topics, not just child-rearing, as ideologically driven. Yet any time biases are corrected, Science comes out ahead. I wish more of my colleagues were more explicit about acknowledging the longstanding presence of androcentric bias within Darwinian theorizing. I am grateful to Tom Givón for his candor about the problem and also struck by a curious coincidence, if it is one. The only other man to specifically comment on this, was also a linguist, Mark Abley reviewing Mothers and Others for the Montreal Gazette.

    http://www2.canada.com/montrealgazette/news/saturdayextra/story.html?id=1a9dc5ec-3ee3-4c9e-a65c-75f7bb934c5f

  • Although “disinterested cooperation” certainly occurs, I know of no cases where it evolves and have never suggested that it did. Possibly Raymond Corbey is arguing with someone else. As for morality, it is not a topic I have written about. For those interested in evolutionary perspectives on morality, I would recommend recent articles and books by Frans de Waal, Marc Hauser, and Randy Nesse.
    Whether one refers back to earlier books where I describe such arguably “cruel and pitiless” behaviors as infanticide by male monkeys who eliminate the offspring of females they never mated with, or reads what I have written more recently about how “cooperative breeding” evolves (which I guess is the part bothering Corbey) there is nothing either evolutionarily odd or metaphysical about my arguments. According to Hamilton’s Rule — one of the central constructs of modern evolutionary theory — helping behavior evolves whenever the cost to the helper (designated as C) is less than the fitness benefits (B) to the individual helped multiplied by their degree of relatedness (r). If the cost is low enough and the pay-offs to recipients sufficiently great, or if there are penalties from not helping, individuals may end up helping nonkin. For example, helpers may occasionally help when they have nothing better to do, or because they are motivated to mollify a more dominant individual in the group, or because they risk loss of a relationship or ostracism if they don’t help. Or perhaps he or she has a stake in the group’s size and continued functioning. Sometimes altruistic help is misdirected towards someone else’s offspring simply because under most circumstances a creature who failed to respond to signals from a needy infant would fare worse on average than if he or she occasionally cared for the “wrong” one.
    Myriad such scenarios are documented throughout the natural world, as are forms of cooperation far more elaborate than shared care of young. (There are no better guides to this topic than E.O. Wilson and Bert Holdobler’s writings on the social insects). Among creatures as highly social and also characterized by helpless young as all primates are, care of infants other than one’s own turns out to be surprisingly common, albeit not among the apes. So far as the Great Apes go, the only apes where we find evidence of a lot of cooperation and also the only apes with alloparental care and provisioning of immatures, are in the line leading to the genus Homo. One of the things I most wanted to understand when I set out to write Mothers and Others then was what the cognitive and emotional implications (including both byproducts and eventual consequences) of such a peculiarly unapelike mode of child-rearing were likely to have been. There are creatures out there exhibiting far higher levels of cooperation in rearing young than humans do. But none of them started out already fairly large-brained, unusually clever, bipedal, tool using, and possessed of rudimentary theory of mind.

  • A theory of minds

    I want to add a postscript to Sarah Hrdy’s provocative essay. My comments are very much in the spirit of her thinking but probe one unexamined implication. As a graphic starting point – and counter-point – conjure up the famous image of Konrad Lorenz, bucket in hand, striding across a field with a retinue of goslings, in tow. Bowlby’s notion of ‘monotropy’ – a more or less singular and exclusive attachment to one figure readily applies. But, as Hrdy argues, it does not fit the human pattern, in which multiple caregivers offer food, reassurance, and information. In what ways might human children be adapted to this multiplicity? Hrdy’s speculation runs as follows: “Then subject this novel ape phenotype to novel selection pressures such that infants best at monitoring the mental and emotional states and intentions of others, and also best at learning from them, are going to be those best cared for and best fed.” On one reading of this proposal, infants with superior mind-reading skills are better placed to take advantage – in a generic fashion – of all such allocentric care. Given the multiplicity of caregivers available, adroit mind-readers would have the opportunity to accumulate benefits across several caregivers whereas slower mind-readers would be multiply disadvantaged.
    There is, however, a different reading. One of the key implications of the Bowlby-Ainsworth research program is that human infants are excellent psychologists, not in the contemporary sense that they recruit a universal theory of mind to make sense of any person that they encounter, but in the more traditional sense that they are good judges of character – they are alert to individual differences in the competence and disposition of their various caregivers. They recognize, at the very least, who is predictably responsive and available, who is predictably unresponsive and unavailable, and who is inconsistent. Moreover, contrary to the conclusions that one might draw from Bowlby’s initial emphasis on monotropic attachment, infants do not extrapolate inappropriately from their history with an initial or primary caregiver to other, available caregivers. They assess each potential caregiver on his or her merits. Thus, in keeping with their skill at judging character, they are selective. They form different types of attachment to different caregivers (van IJzendoorn & De Wolff, 1997). Gross distortion of normal rearing conditions for human infants, on the other hand – most recently studied among children who spent months or years in the state-run orphanages of Rumania – often leads to a deficit in this same capacity for selectivity. Such children make indiscriminate contact with others, including strangers (Rutter et al., 2007).
    My guess is that under normal rearing conditions selectivity continues throughout development, determining not just the person that the infant seeks out for comfort and reassurance, but also the person – or persons – that the toddler and young child look to for information about cultural practices, especially in the domains of language and tool use. Indeed, evidence is rapidly accumulating that children are quite selective in these matters, preferring to seek and accept guidance not just from familiar caregivers but from those who have a history of accuracy or of group endorsement (Corriveau, Fusaro & Harris, 2009; Corriveau & Harris, 2009; Fusaro & Harris, 2008).
    In sum, I believe that Sarah Hrdy has put her finger on a key question concerning human ontogeny and phylogeny: what type of mind-reading is adaptive in the context of allocentric child-rearing? My proposal is that there has been pressure on children to be selective, not just about their caregivers, but also about their teachers – those from whom they seek and accept guidance. Good mind-readers do not simply accumulate the same benefits across multiple caregivers; they work out whom to trust for what. They have a theory not of one single, universal mind but of the various minds that they encounter.

    REFERENCES

    Corriveau, K. H. & Harris, P.L. (2009). Choosing your informant: Weighing familiarity and recent accuracy. Developmental Science, 12, 426–437

    Corriveau, K. H., Fusaro, M., & Harris, P.L. (2009). Going with the flow: Preschoolers prefer non-dissenters as informants. Psychological Science, 20, 372-377.

    Fusaro, M. & Harris, P.L. (2008). Children Assess Informant Reliability Using Bystanders’ Non-Verbal Cues. Developmental Science, 11, 781-787.

    Rutter, M., Colvert, W., Kreppner, J., Beckett, C., Castle, J., Groothues, C., Hawkins, A., O’Connor, T G., Stevens, S. E., & Sonuga-Barke, E. J. S. (2007). Early adolescent outcomes for institutionally-deprived and non-deprived adoptees. I: Disinhibited attachment. Journal of Child Psychology and Psychiatry, 48, 17-30.

    van IJzendoord, M.H. & De Wolff, M. S. (1997). In search of the absent father—meta-analysis of infant–father attachment: A rejoinder to our discussants. Child Development, 68, 604-609.

  • Ethnographers who have actually studied small, band-level hunting and gathering societies overwhelming confirm what the Marshall team reported decades ago among the determinedly egalitarian Ju/wasi Bushmen. These people go to extraordinary lengths to get along both with other group members and with near-by neighbors. To this day, descriptions of their way of life provides the best evidence anthropologists have for understanding the challenges that Pleistocene hominins faced in rearing young as well as for reconstructing other aspects of our ancestors’ environments of evolutionary relevance. Thus the elimination of this ancient way of life so beautifully described in the writings of Mel Konner, Richard Lee, Lorna Marshall, Polly Wiessner and Elizabeth Marshall Thomas herself, is one of the great scientific as well as humanitarian tragedies of our time. New genetic evidence indicating that the San population Thomas is talking about split off and essentially remained separate from other human populations for more than 35,000 years (Tishkoff et al. 2007) is consistent with Thomas’ interpretation of the archeological evidence. It also underscores the magnitude of our loss.

    Tishkoff, Sarah, et al. 2007. History of click-speaking populations of Africa inferred from mtDNA and Y chromosome genetic variation. Molecular Biology and Evolution 24(10): 2180-2195.

  • Move Over, Machiavellian Alpha Males: Humans Evolved When Children Were Inventive Enough to Solicit Continued Caregiving

    Those of us who regularly browse the popular and scientific literature for new ideas about what makes us uniquely human have been treated to a dizzying succession of breakthrough theories about human evolution over the last decades. We grew up with the obvious explanation that the crucial actor was “man the tool-maker.” Tool-making fit the emphasis in the mid-20th century that logic and abstract thought are the hallmarks of higher cognition, regarded as the most important aspect of being human. Even in the 1970s, social and emotional domains were maligned, seen as poor cousins next to the central domains studied by real scientists: artificial intelligence, information processing, and syntax, not semantics (see Gardner, 1984, The Mind’s New Science).

    It was thus a shock in the 1980s to witness hunting and tool use flung aside as lesser causes when Byrne and Whiten published Machiavellian Intelligence: The Evolution of Intellect in Monkeys, Apes, and Humans in 1988. [I see now after I prepared my reply that Tom Givón also discusses this recent history in his reply.] The new view rapidly gained acceptance: succeeding in the ancestral social environment required predicting what conspecifics would do, in order to outwit them while climbing the social hierarchy. Although human planning and abstract reasoning could be used to create calculus or construct mental representations of the cosmos, such scientific inventiveness was merely the side-effect of the need for clever backstabbing and social maneuvering.

    Hrdy’s proposal delivers a similarly forceful revolution. She agrees that the need for social abilities was a crucial driver in human evolution. But the standard social intelligence hypothesis revolved around adult males, from the three outsider chimps who colluded together to take down the alpha in De Waals’ riveting chimp melodrama, Chimpanzee Politics, to contemporary cigar-smoking Mafiosos who cannily knew how to pit one rival against each other as in the Sopranos. In Hrdy’s account, the change agents are children and their caregivers (frequently female), children competing with each other to receive the additional care that will allow them to survive the extended childhood required for massive social learning.

    Not surprisingly, Hrdy’s ideas have been presaged by others. In 2006, to explain how the social skills for language evolved, language acquisition expert John Locke proposed the parental selection hypothesis: “infants who issued more effective care-elicitation signals (e.g., measured or strategic levels of cry) were better positioned to receive care than infants who issued stress vocalizations noxiously or insolubly — behaviors that invite neglect and abuse in primates generally, and forecast language-learning problems in humans” (see Locke and Bogin’s target article in Behavioral and Brain Sciences, 2006). As part of their “Life history theory,” Locke and Bogin note that new developmental stages occur in humans that do not appear in other species. One of these is childhood (ages 2-6 years), a period of continued high dependence interposed between infancy and the more independent juvenile period. The other is adolescence (10-18), a period of intense social learning and apprenticeship, with non-adult status despite reproductive maturity. Locke and Bogin argue that the major goals of these stages are to increase the social and language skills necessary for adult competence.

    In the 20th century, emotion and social influences were regarded as wishy-washy (possibly too feminine?) and were ignored by the paradigm shift that occurred from 1940-1960 called the Cognitive Revolution. It is interesting to see the social realm now reign supreme in the eyes of leading scientists. Perhaps we’ll stop compartmentalizing our study of human nature into the classic subfields of psychology (cognition, emotion, social, developmental) and find new ways of conceptualizing the interactions of what must be a complex dynamical system. Hrdy’s work and the primate and evolutionary studies she reviews are a major step towards our evolving understanding of who we are.

  • Camilla Power

    The interdisciplinary range of Hrdy’s thesis in Mothers and Others is reflected by the breadth of different disciplines represented by those who’ve already responded to this essay. As ever with Hrdy this makes for exciting science, seeking parsimony in uniting perspectives from different fields.

    I’m an evolutionary anthropologist particularly interested in Darwinian modelling for the emergence of symbolism, whether that’s linguistic, ritual, religious, artistic. All of human life, in all cultures, organises their most important affairs – allocation of food, allocation of sex partners – through systems of collectively shared fictions. That’s a hell of a difference from any other extant ape. What intrigues me most in relation to Hrdy’s argument – which I strongly support – is how much difference between us and Homo erectus? If H. erectus was, H. heidelbergensis and Neanderthals besides evolving H. sapiens were all presumably cooperatively breeding apes too. It would be hard to argue otherwise, given their expanded brain sizes, which place even more stress on the energetic requirements for mothers. If we accept Hrdy’s basic hypothesis, what were and why were there differences among all these species?

    Hrdy states very clearly that she’s dealing with the prequel, but she signposts down a specific evolutionary road that should give us more power to make predictions against the fossil and archaeological records. Although she stresses demographic flexibility in her cooperative breeding model, it is fundamentally a sewing together of Kristen Hawkes and colleagues’ ‘grandmother’ hypothesis with the Tomasello school of developmental psychology, which highlights intersubjectivity, that is, a willingness to share what I am thinking with you, and seek to know what you are thinking of my thoughts, apparent even in very young children. It’s important to stress that ‘intersubjectivity’ is something over and above ‘theory of mind’ because it denotes a two-way traffic in mindreading and necessitates allowing one’s own mind to be read. Chimpanzees don’t do that, unless acculturated to a human world. Given their politics of Machiavellian power struggle, natural selection is not likely to favour a chimp who gives away its thoughts to others.

    In this view then, H erectus world was very different from chimp world. Early H erectus, from about 1.8-1.5 million years ago, remains an enigmatic creature, suspended somewhere halfway between apelike and humanlike lifeways. Not really like chimps, but not really like us either. Archaeologically there is no secure evidence of life by a hearth, and no suggestion of symbols, art, ritual or language. Evidence from the key specimen, the sub-adult ‘Nariokotome’ boy of 1.5 mya, is somewhat contradictory about how fast he would have grown up and matured; aspects of dentition remain apelike, suggesting a fast-track to maturity closer to chimps than to us (Dean et al. 2001). Yet, with the brain twice as big as a chimp’s, and larger body size, this hominin must have been living comparatively longer, and becoming sexually mature later.

    James O’Connell, Kristen Hawkes and Nicholas Blurton Jones in their original ‘Grandmothering and the evolution of Homo erectus’ article (1999) located precisely the palaeoclimate, archaeological and fossil contexts for the onset of these behavioural changes, producing a parsimonious model for evolution in the direction of all the special characteristics of human life history: not only longer lifespans – notably women’s long post-reproductive lifespan – and delayed sexual maturity, but also the puzzling combination of early weaning with short interbirth intervals going along with longterm childhood dependency. With accessible resources for vulnerable weanlings failing in the drying climate, those juveniles who had mother’s mothers alive to help them find and process food would survive better, improving the mortality rate, enabling selection for longer lifespan, and particularly selection on females living past reproduction (incipient menopause). Those mothers who had helper mothers available would be able to wean earlier and reproduce faster. This cooperation in production and reproduction between grandmother, mother and offspring not only accounts for evolving human life history but also the shared cooperative goals that Tomasello, and Hrdy, argue are the basis for intersubjectivity.

    Peter Ellison’s suggestion that we should also examine cooperation in production is well taken, since we need to know as much about H. erectus economics and distribution of resources as possible. However, the point about the grandmother model is that cooperation in both production and reproduction evolve hand in hand. And once this shift in behaviour occurs, a whole cascade of consequences, some of which are brought alive by Hrdy, some of which we don’t fully understand yet, would be in train.

    The number one point to make about the grandmother model and Hrdy’s extension of it to cooperative breeding is that they rest on female kin sticking together as a default in Homo. Hawkes, Hrdy and several other contributors to volumes on grandmothering strategies and early human kinship (Voland et al 2005; Allen et al 2008) are now establishing this as a revolutionary new orthodoxy, opposed to the old-fashioned and ideologically coloured notion of ‘patrilocal bands’ (see Knight 2008). We now need more testing of palaeontological and archaeological models which adopt this starting point and explore its ramifications.

    The second major point to make about the Hawkes plus Hrdy trajectory is that both leave males somewhat in the margins, and the issue of how males became involved in investment in increasingly large-brained and demanding offspring is left cloudy. Hrdy does provide rich evidence on the endocrine systems of sensory entrapment by which babies can get dads, or brothers or uncles to fall in love with them. But I’m still thinking of Homo erectus as this transitional halfway house. Hrdy is perfectly right to argue that people have done an awful lot of thinking, or fantasising, about male-female relations and sexual selection in hominin evolution, and comparatively little about the all important childhood development issues. For both Hawkes and Hrdy, female kin get on with the job, since they can’t rely on males being reliable. The demographically flexible cooperative breeding networks Hrdy envisages act as child welfare safety nets compensating for the extreme variability of male commitment to investment.

    Because female fertility is altered by the grandmother strategy, since mothers with allocare support would tend to have shorter interbirth intervals and be fertile more often, this must affect male behaviour. Potential male strategies in response could vary. More dominant males might attempt to target fertile females opportunistically, roving from one to another, while less dominant males could pursue a strategy of hanging around more regularly, offering provisioning and protective support to a particular female and her kin. As interbirth intervals shortened, investor males who waited around, rather than competed for other mates, should get more reproductive payoffs. Such a picture of variability in male commitment fits Hrdy’s observations of stark differences among even modern human fathers.

    Hawkes and colleagues of course have a further hypothesis about male investment for a subsequent stage, drawing on their observations of Hadza hunters who vastly prefer to hunt big game, even though this means they may be successful less often. During the Middle to Late Pleistocene (associating to Homo heidelbergensis), hunting strategies become more effective and reliable. Males were motivated to hunt big game as ‘show offs’. Rather than hunt small to medium game for their own offspring alone, they demonstrated quality by generously providing big game to the whole camp (Hawkes and Bliege Bird 2002). So females gained male investment via mating effort rather than specifically paternal strategies. However, there is no strong argument from Hawkes as to what causes the shift in male behaviour and productivity between Homo erectus and later encephalized humans.

    My view is that we should follow through the logic of cooperative breeding strategies and female coalitions as the basis of human social organisation into the last half million years of the Mid to Late Pleistocene (c. 500,000 to 130,000 years ago), when H. heidelbergensis and its descendant sister species, ourselves in Africa and the Neanderthals in Eurasia, rapidly expanded brain sizes to over triple that of chimpanzees. If males got their act together to start supporting the cooperative breeding enterprise in this period, which appears in archaeological evidence, then it very likely was female kin coalitions who got them organised. That they succeeded in gaining the extra energetic investment is proved by the extraordinary expansion of brain size. The precise sexual selection models that emerge give us not only a parsimonious account of human life history, and the cooperative basis for intersubjectivity, but also yield testable hypotheses for the emergence of symbolic strategies as the matrix for ritual, language and art (see Power 2009). The Female Cosmetic Coalitions model is currently the only behavioural ecological account which explains the archaeological record of red ochre usage, ochre ‘crayons’ and engraved pieces of haematite, alongside shell beads, now revealed as the earliest evidence of symbolism in the African Middle Stone Age, arising with our species (Watts 2009).

    Allen, N. J., H. Callan, R. Dunbar and W. James (eds) 2008 Early Human Kinship. From sex to social reproduction. Oxford: RAI/Blackwell Publishing.
    Dean, M. C., M. G. Leakey, D. Reid, F. Schrenk, G. T. Schwartz, C. Stringer and A. Walker 2001. Growth processes in teeth distinguish modern humans from Homo erectus and earlier hominins. Nature 414, 628-631.
    Hawkes, K. and R. Bliege Bird 2002. Showing off, handicap signalling, and the evolution of men’s work. Evolutionary Anthropology 11, 58-67.
    O’Connell, J. G., K. Hawkes and N. G. Blurton Jones 1999. Grandmothering and the evolution of Homo erectus. Journal of Human Evolution 36, 461-485.
    Knight, C. 2008. Early human kinship was matrilineal. In N. J. Allen, H. Callan, R. Dunbar and W. James (eds) Early Human Kinship. From sex to social reproduction. Oxford: RAI/Blackwell Publishing, pp.61-82.
    Power, C. 2009 Sexual selection models for the emergence of symbolic communication: why they need to be reversed. In R. Botha and C. Knight (eds) The Cradle of Language. Oxford: Oxford University Press, pp. 257-280.
    Voland, E., A. Chasiotis and W. Schiefenhövel (eds) 2005. Grandmotherhood. The evolutionary significance of the second half of life. New Brunswick, NJ: Rutgers University Press.
    Watts, I. 2009. Red ochre, body painting and language: interpreting the Blombos ochre. In R. Botha and C. Knight (eds) The Cradle of Language. Oxford: Oxford University Press, pp. 62-92.

  • Cuteness in Manga and Anime

    I’d like to pick up on Hrdy’s discussion of alloparents and the following remark by Michele Pridmore-Brown:

    “As for children themselves, it is no accident that, as I have discussed elsewhere (Times Literary Supplement, May 22, 2009), the winsomeness of famous characters like Pip in Great Expectations or Heidi in the children’s story of that name or the orphan girl in Silas Mariner are crucial to the unfolding of their creators’ plots. That winsomeness is in fact the narrative motor of countless tales—whether it’s the winsomeness inscribed in physical features or of the mind-reading connection-seeking variety or, most often, a combination of the two.”

    The winsome characters that interest me are all those large-headed and large-eyed characters in manga and anime, Japanese comics and cartoons, respectively. It would be one thing if those and associated traits (think of Konrad Lorenz’s infant schema) were used only in depicting infants and toddlers, where they are representationally appropriate. But that’s not at all the case. Those traits are also quite common in the depiction of older children, teens, and adults. Why?

    For those who aren’t familiar with manga and anime, let me say that I broach this issue because these particular visual characteristics are among the first things people notice upon becoming acquainted with these works. Though not a universal practice, their use is quite common and quite striking. It’s a question that always comes up in introductory commentary, whether in hardcopy or online media. Now …

    Given that the characters in these stories act in age-appropriate ways (according to the conventions of the particular imagined universe) it doesn’t make much sense to think of this as an infantilization of the characters – though that has been suggested by Takishi Murakami, a Japanese artist and culture critic. I suggest, instead, that the pervasive use of these traits is directed at the audience, inviting us to consider these characters, of whatever age, as though we were their alloparents. Thus we have a parental concern for their welfare even though they may be a bit wayward; we’re willing to indulge them, e.g., as they experiment with gender roles (as they often do).

    Alas, I’m not in a position to cite a strong argument on this point and so I offer it only in the spirit of speculation. Continuing in that spirit, I have some other observations.

    In the first place, if the speculation is to have any force at all, it implies that we do not routinely assume the role of alloparents to fictional characters. What role(s) do we routinely assume? As far as I know, we don’t know. Empirical research on audience response is sparse and qualitative research is only less-than-sparse. In either case, I do not know that this issue having been addressed. The default assumption seems to be that we respond in our own person, whatever that may be.

    Still, why are these traits so prevalent in manga and anime? The use of these traits is not confined to manga and anime; they certainly appear in other cartoons and comics. However, while manga and anime have existed in Japan since the early 20th century, they have flourished after WWII to an astonishing extent. Manga and anime have been particularly inventive in exploring gender roles and they have been open to a wide variety of cultural influences. Does encouraging alloparental reading and viewing somehow facilitate cultural transition and transformation? The question is not exclusively a Japanese question as manga and anime have migrated out of Japan over the last two or three decades and have (arguably) become pervasive in international youth culture.

    And just who is the audience? In Japan the audience of manga and anime certainly includes teens and adults as well as children. The situation in the United States is a bit different. Since WWII cartoons and comic books have been regarded as media for children, which was not the case pre-war. But this is only one aspect of the question.

    Regardless of whatever assumptions obtain in a given locale, what does it mean for a six-year-old to play at being an alloparent to fictional characters and what does it mean for a twenty-six-year-old to do the same? I haven’t the foggiest idea.

    At this point we’ve got two sets of issues occasioned by certain representational traits in manga and anime. One set of issues centers on how individuals enact the role of reader (of manga) or viewer (or anime). One isn’t simply being oneself. Something else is going on, something having to do with how you regard the characters in the story. The old standby of “identification” won’t do. The other set of issues has to with social and cultural practices concerning the reader’s or viewer’s role. Under what circumstances is that role framed as being an alloparent to the characters in the story? Why Japan after WWII?

    Needless to say, sorting through these matters is not going to be easy.

  • Jacqueline Solway

    Hrdy must be lauded for her lucid and compelling account of human evolution. By attributing the source of human intersubjectivity and ultimately human culture and language to the extension of infant and child care beyond the dyadic relationship of biological mother-child, she contributes to a long-standing debate in anthropology that I will address below. In addition, as she and other commentators have noted, she offers not only further understanding but also an implicit means of redress for contemporary social pathologies connected to the absence of alloparenting and the associated social isolation of mothers. Therefore, the significance of her findings goes beyond their profound evolutionary implications and suggests an avenue to more effectively confront problems facing contemporary parents and children who lack social networks.

    As a social-cultural anthropologist I lack the expertise to address the evolutionary questions raised by Hrdy and her interlocutors; therefore I will confine my comments to resonances between Hrdy’s account of human or proto human origins and key debates within the anthropological study of kinship, debates that have broader epistemological implications for the study of human society. I then extend the discussion to consider Hydy’s analysis in light of observations based upon three decades of fieldwork amongst Kalahari residents, including former foraging peoples.

    In reading Hrdy’s account I am struck by how her hypothesis on the role and significance of alloparenting and intersubjectivity in our ancestors’ child rearing practices appears to support, as much as an hypothesis regarding our unobservable evolutionary heritage can, the theories put forward by early social evolutionists such as Lewis Henry Morgan (1870) regarding the origins of human society and human social organization.

    Morgan’s specific evolutionary outline has been rightly criticized for being overly speculative and empirically wrong in many instances. No proof exists for the postulated pre-historic stage of primitive promiscuity and group marriage that he predicated upon an existing system of classificatory kinship terms in which biological parents and children were not distinguished from their siblings or other collateral relatives. The evolutionists’ subsequent stages of social organization, based largely on available empirical data at the time, reveal a ‘progressive’ shrinking of kinship groupings with the eventual emergence of the nuclear family, and not coincidentally, less alloparenting.

    The details of Morgan’s and others’ analysis are not apposite here but what is important to note is that the starting point is the collective and not the nuclear family or even the irreducible biological mother-child relationship that has been central to alternative kinship theories; in particular to Malinowski who argued for the primacy and universality of the nuclear family and universal significance of the biological mother-child bond. This bond provided the fundamental building block of society and kinship terminology extended out according to a ‘kinship algebra’ (Malinowski 1930).

    For Morgan, Engels (1972) and others, kin relations, including those entailed in parenting, were to be read ‘down’ or ‘inwards’ from the collective and not out from a dyadic relationship. Even after the supposed stage of group marriage when biological mother-child relations attained recognition, it was assumed that the role of mothering/parenting was still carried out by numerous, possibly interchangeable, adults who bore the same designated kinship relationship to the child. If Hrdy is right, then her argument lends support to the general approach of the evolutionists who, in their quest to understand the human social condition, started with a focus on the group and not on a specific dyadic relationship.

    In sum, if Hrdy is right, that alloparenting preceded human language, and the evolutionists are right in interpreting classificatory kinship systems as implying cooperative child rearing, then the two hypotheses reinforce one another. Further, if the evolutionists were correct, then the erosion of alloparental care as the default human condition is a more recent phenomenon than some have thought it to be. Alloparenting is not simply a convenient support for otherwise isolated mothers.

    In my own research in the Kalahari, Botswana among both San former foragers and Bantu-speaking Kgalagadi, I observed alloparenting to be the norm. However, unlike the scenario identified by Givón above, biological mothers do not necessarily voluntarily read the intentions and emotional dispositions of others and then entrust their newborns to them — they often have little or no choice. Alloparents abound and in many cases if the alloparents are in a senior relationship to the mother, they claim their right to care for the child and in some instances, to take the child and assume primary parenting rights, rarely, if ever, over the objections of biological mothers.

    As the Kalahari debate of the 1990’s highlighted, it is dangerous to project the contemporary behaviour of recent foragers to a Pleistocene past; all extant peoples have a history and multiple events and influences impact upon the present. However, with the greatest of prudence, if we can infer anything about our ancestors from the behaviour of existing recent hunter-gatherers, we can adduce widespread alloparenting, a great deal of cooperative child rearing, much of it embedded in kinship systems bearing resemblance to those depicted by Morgan and other evolutionists in which the responsibilities for raising the next generation and provisioning for their material welfare do not fall only to one or even a few people but are, in a general sense, the responsibility of a broader collective.

    REFERENCES
    Engels, Frederich (1972 [1884]) The Origin of the Family, Private Property and the State. New York: International Publishers.

    Malinowski, Bronislaw (1930) Kinship. Man 30:19-29.

    Morgan, Lewis Henry (1870) Systems of Consanguinity and Affinity of the Human Family. Washington: Smithsonian Institution Press.

  • Reply to Benzon, Caldwell-Harris, Solway, and Power:

    As I read Jacqueline Solway’s reminder about Lewis Henry Morgan’s long-ago views on collective parenting my first thought was to tell her about recent books and articles by Camilla Power and Chris Knight. Minutes later, Camilla Power’s cogent summary of her views arrived in my in-box, and is now posted at OTH. I can not improve on her concise summary of the relevant literature. Solway is correct of course, that there were serious problems with Morgan’s and Engel’s ideas — particularly Morgan’s notions about “stages” in human evolution. But as both Power and Solway are aware, this does not mean these early theorists were wrong about everything. I agree with Power that what we need now are tests of archeological and paleontological models which start out by reassessing and reconsidering long dismissed views about collective child-rearing.
    In addition to the oft-noted androcentric biases, much of the problem here has to do with disciplinary compartmentalization. On this point, I completely agree with Catherine Caldwell-Harris. Thus in addition to archeological, paleontological, demographic, genetic and ethnographic evidence, folklore and emerging information from neuroscience and the comparative study of both infant development and parental and alloparental responses, this revised model-building needs to be informed also by sociocultural studies of caretaking such as Jacqueline Solway is now doing among former foragers. Bill Benzon suggests we consider taking into account the source of the appeal behind anime characters as well, and he may be right. I don’t know enough about anime to comment, but surely casting wide the net to encompass diverse perspectives is the point of this Forum.

  • According to my friend Tom Givón, in his post above, “Evolutionary primatologists have long come to a near consensus that our ‘mind-reading’ capacity…is the key to the special evolutionary adaptation of the hominid line”. Hrdy’s linkage of this, a clearly necessary prerequisite for full language (though perhaps not quite so necessary so for some kind of intermediate protolinguistic form), with the need to explain human cooperation is a step in the right direction, although something that would make both sexes cooperate might seem preferable. But without language, even with mind-reading, humans would be no more than upgraded bonobos. And mind-reading by itself can’t even begin to explain how the breakthrough into language took place. For even a protolanguage, you have to have true (not “functional”) reference and displacement, and if someone can explain to me how mind-reading gives you these, I’ll be delighted (and amazed). For a very different explanation of how we got to be human (that is not inconsistent with, but would certainly supplement, Hrdy’s) see Bickerton 2009–sorry, it would take too long to summarize here, but it goes in depth into all the aspects of language and mind that are most disregarded by Tom’s “near consensus”.

    REFERENCE:
    Bickerton, Derek. 2009. Adam’s Tongue: How Humans Made Language, How Language Made Humans. New York: Hill & Wang.

  • There are all kinds of feedback processes in human evolution, so that perhaps it makes little sense to try to single out one specific cause or ingredient as the one which made humans human—but then reasoning demands that you should analyze these processes, instead of just pointing to the whole interacting lot. In this sense, Hrdy’s allomothering theory of sociality is of course illuminating and welcome. It may also provide a significant contribution to the theory of mind-reading, and once we have a primate with mind-reading abilities and the cooperative social structure required by this mode of child rearing we get much closer to defining human specificity. Of course there are many other ingredients left unaccounted for. Derek Bickerton points out that this does not account for the appearance of linguistic meaning and displaced reference, and indeed it doesn’t. This element too is crucial (perhaps “the” crucial one, pace myself) in articulating the communicative world that we recognize as human—although of course ‘human’ is a fuzzy concept, as it is defined by kinship and a potentiality for communication, not only by actual communicative interaction. One wonders though, if we keep on isolating ingredients in the human, what would be the value of an ability for displaced reference and meaning without any concomitant advanced abilities in mind-reading. Perhaps that might leave us as no more than upgraded bees, as against Bickerton’s upgraded bonobos! Human communication seems to require both language (meaning and reference) and mind-reading—that is, not just “knowing what someone says” but also “knowing what they actually mean”, or what they are trying to do with words. Social intelligence is so much an ingredient of language that it is actually the (moving) ground on which language is built.

  • Richard Reed

    Sarah Hrdy’s recent work on the evolutionary dynamics that underlie the development of empathy have interesting implications for fathers, especially in their roles nurturing mothers and infants. This is interesting given current family structure in our post-industrial society.

    Hrdy suggests that a mother’s empathic responses are contingent, not only on her relation with an infant, but on her network of social relations. This includes a multiplicity of allomothers, fathers, sisters, mother, aunts and cousins with whom she lives, and on whom she may be mutually dependent. (It is important that Hrdy prefers to consider fathers “allomothers”, sidestepping the zoological term “alloparent”.) A mother benefits from the support of these allomothers, not only through their attention to her infant, but in the development of her own empathic relationship with the baby.

    For fathers, this idea raises interesting suggestions about the importance of men in an infant’s life, not simply in paternity, but indirectly through relation with mothers. Early research on men and fatherhood tended to consider men’s involvement as mating behavior, energy expended prior to conception. More recent research of fatherhood in small scale societies suggests that paternal attention has a direct impact on an infant’s chance of survival after birth , and that multiple fathers increase that chance even more . What studies of paternity often fail to attend to, however, is the importance of the father in the “birth triad,” that is in relation to both the mother and child. Hrdy’s attention to empathic relations between mothers and allomothers embeds an infant in a community of caregivers, including mothers and fathers and a diversity of female kin. This becomes a mutually supporting group, which like the strings of a hammock support each other as the entire cloth holds the infant.

    As postindustrial pressures force human into smaller and smaller nuclear units, fathers assume ever more-important roles in the diminishing circle of allomothers. The effects are felt in every hospital birthing room I’ve observed, where fathers (not mothers or aunts or sisters) are asked to provide the primary emotional support for birthing mothers. And I have no doubt that many a mother has had an easier time relating to her new baby because of the support of an empathic father!

    REFERENCES
    Hill, Kim and Magdalena Hurtado. (1995) Ache Life History. New Jersey: Aldine de Gruyter.
    Beckerman, S., Valentine, P., (eds) (2002) The Theory and Practice of Partible Paternity in South America, Miami: University Press of Florida.

  • Reply to Bickerton and Angel:

    I love Jose Angel’s image of upgraded honeybees, and agree with him that multiple feedback processes must have been involved in the evolution of Homo sapiens and agree also with Derek Bickerton that language and the processes shaping it were critically important in terms of what makes us the intellectually curious and argumentative species we are today. About all I have to say about language though can be found on pp. 37-38 of Mothers and Others in a section labeled “Logically, Language Comes Later”. It reads:

    Unquestionably, the uniquely human capacity for language enhances our ability to connect with others and exponentially increases the complexity of the information we can convey. But language is not just about conveying information, as in warning others to “Look out!” An animal alarm call does that. Even vervets (which are Old World monkeys after all, not even apes) have specific calls that alert conspecifics to danger and also inform them whether the threat is from the air and likely to be a predatory bird, as opposed to something scary on the ground, like a snake. Honeybees convey surprisingly precise information about the location of food (how far away and in what direction) by the type and duration of their ritualized “dance” movements. Animals have all kinds of ways of communicating information about their environment or state of arousal… (note 14).
    The open-ended qualities of language go beyond signaling. The impetus for language has to do with wanting to “tell” someone else what is on our minds and learn what is on theirs. The desire to psychologically connect with others had to evolve before language. Only subsequently do the two sets of attributes co-evolve. As (the psychiatrist Peter) Hobson puts it, “Before language, there was something else—more basic . . . and with unequalled power in its formative potential.” (note 15). If we are looking for sources of human empathy, these emotion-laden quirks of mind had to evolve before language. Even before humans began actually speaking to one another in a behaviorally modern way, their immediate hominin ancestors already differed from other apes in their eagerness to share one another’s mental states and inner feelings. In this sense, these creatures were already “emotionally” modern long before they became “anatomically” or “behaviorally” modern” and were routinely using speech to converse with one another (more on this chronology in chapter 9). The ancestors of people who acquired language were already far more interested in others’ intentions and needs than say chimpanzees are. What we need to explain is why.

    In Mothers and Others that is as far as I sought to go. The rest of the fascinating and very complex story about how human language evolves I leave to Tom Givon, Derek Bickerton, Jose Angel and others to tell us.

  • Parker Shipton

    We are sorry that the time has come to close this most interesting discussion, but we invite those who may wish to continue corresponding on the topic to do so in our Facebook group, http://www.facebook.com/group.php?gid=52472677549.

    We thank our featured essayist Sarah Blaffer Hrdy and all those who have sent in their responses, offering such diverse perspectives.

  • Tom Givón

    Sarah Hrdy has suggested that I might want to respond to the exchange between her and my good friend Derek Bickerton, given that the connection between her work on the evolution of mind reading and the evolution language may be of general interest. In his response to Hrdy, Bickerton raised two separate issues. I will deal with them in order.

    Animal communication and pre-linguistic childhood communication (roughly in the first year of life) share two fundamental characteristics above and beyond the absence of coded vocabulary and grammar: (i) Non-displaced reference; that is communication only about here-and-now, you-and-I, this-and-that-visibles. The past and non-immediate future may or may not be contemplated, but they are never communicated about. And (ii) the total absence of informative–declarative and interrogative–speech-acts; so that communication is confined to manipulative gestures, be they requests, commands, warnings or solicitations. What Bickerton asked at the end of his note, perhaps somewhat facetiously and implicitly, is how would Theory of Mind explain the evolution of displaced reference; that is, of communication about remembered past events or planned future actions. The immediate answer is that there is no direct causal connection. But this is only part of a complex story.

    In his recent book “Adam’s Tongue” (2009), Bickerton outlines one possible selectional pressure that could have led to the rise of displaced-reference communication in the hominid line–planning for big-game scavenging. The crucial ingredients are indeed there–the existence of adaptive-vital information that is not about here-and-now but about there-and-then, and further is not shared equally among group members. In all fairness, however, other proposed selectional pressures would qualify just as well by the same cluster of criteria: Planning for a group big-game hunt, planning for inter-group warfare, reporting on big-game presence elsewhere, reporting on enemy presence elsewhere, scouting reports on desirable faraway new territory, and more. (For a thoughtful review of such a list, see Számadó and Szathmáry 2006).

    The second issue, raised obliquely in Bickerton’s contribution to this forum but more extensively in subsequent communications, is the relevance of mind-reading to human communication in general, and in particular to pre-grammatical pidgin, a communicative mode that Bickerton (1981) had re-christened as “proto-language”. Since I have written extensively on this issue (e.g. Givón 2005), the following is but a tip-of-the-iceberg reminder. The best-known early arguments for the relevance of Theory of Mind to human communication were made by two philosophers, J. Austin (1962) and H.P. Grice (1968/1975). They involve the difference between the use of declarative, interrogative or manipulative speech-acts. Both Austin and Grice point out that the implicit assumptions a speaker entertain about the hearer’s current belief and intention states are radically different in the use of these three speech-acts. What is more, such knowledge is embedded in a network of socially-shared conventions of usage and propriety, whose violation by the speaker are immediately noted by the hearer. In pre-grammatical pidgin, a single noun, say “apple”, may stand for either “This is an apple” (declar.), “Where is the apple?” (interrog.), or “Give me the apple?” (imper.). But while the speech-act distinctions may not be coded by grammar, both speaker and hearer observe their usage conventions (?felicity conditions’) just as stringently. The same Theory-of-Mind dependence of communicative acts, be they grammatical or pre-grammatical, has been shown in multiple areas of human discourse (Givón 2005). As two great primatologists, D. Cheney and R. Seyfarth (2007) have sagely observed, “mind reading pervades language”. So while Sarah Hrdy may not have set out to talk about language evolution, by elucidating a plausible adaptive pressure for the rise of Theory of Mind, she inadvertently also elucidated one of the core adaptive pre-requisites for the genesis of symbolically-coded human communication.

    References

    Austin, J. (1962) How to Do Things with Words, Cambridge, MA: Harvaerd University Press
    Bickerton, D. (1981) Roots of Language, Ann Arbor: Karoma
    Bickerton, D. (2009) Adams’ Tongue, NY: Farrar, Strauss & Giroud
    Cheney, D. and R. Seyfarth (2007) Baboon Metaphysics, Chicago: University of Chicago Press
    Givón, T. (2005) Context asa Other Minds: The Pragmatics of Sociality, Cognition and Communication, Amsterdam: J. Benjamins
    Grice, H.P. (1968/1975) “Logic and conversation”, in P. Cole and J. Morgan (eds 1975) Speech Acts, Syntax and Semantics, 3, NY: Academic Press
    Számadó, S. and E. Szathmáry (2006) “Competing selective scenarios for the emergence of natural language”, Trends in Ecology and Evolution, 2

  • What Paul Harris offers is much more ambitious than a postscript. Given an “emotionally modern” human interested in the mental states and intentions of others, and eager for intersubjective engagement with them, what next? Paul Harris suggests that such creatures will selectively “assess each potential caregiver on his or her merits”, discriminate between them, and learn to be increasingly selective. Absolutely. This is certainly what I believe as well. Furthermore, as individuals mature (and also as the species evolves in such a direction), capacities for assessing the attributes and intentions of different caregivers and other social partners will become more and more sophisticated, and as they do, one might expect individuals to become increasingly aware that others are doing likewise. For those interested in understanding the roots of morality, Harris’ postscript provides as good a starting point as any. For example, the psychiatrist Randy Nesse who (unlike me) actually studies and writes about the origins of moral behavior proposes that people are inclined to behave in a socially acceptable or “moral” way because they want others who value trustworthiness etc. to select them as social partners. Nesse (2007) invokes the process known as “social selection” (a broader variant of Darwinian “sexual selection” developed by evolutionary theorist Mary Jane West-Eberhard) to explain how such behavior and preferences evolve. Paul Harris, Marinus van IJzendoorn and others studying child development are providing new approaches and tools for understanding topics like the origins of morality that once upon a time were the sole preserve of those trained in Philosophy and open to few others. I will continue to follow their groundbreaking research with the greatest interest.

    Nesse, R.M. 2007. Runaway social selection for displays of partner value and atruism, Biol. Theory 2(2):143-155.

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