The Species-Normal Experience for Human Infants: A Biological and Cross-Cultural Perspective
Our pedigree for successful mothering
In seeking the best way to rear infants and meet their needs, it is instructive to consider our ancestral pedigree to gain some understanding of the common biological givens, which we all inherit as human beings. Breastfeeding mammals have been on earth for at least 100 million years. Those who were recognizably human extend back about 5 million years, and apes have been on earth for about 15-20 million years.
To glimpse the amazing scale of your own pedigree, you may imagine a procession, starting with your own mother and grandmother; they are followed in order by all your direct maternal ancestors. Each embraces her daughter, so that four generations - covering one hundred years - are in each meter. Twenty meters will take you back 2000 years. In a hundred meters you can review the line of your direct maternal ancestors for the past 10,000 years. But to go back 5 million years you would travel 50 kilometers, past an unbroken line of your own mothers!
It is safe to assume that, over the millennia, some 99% of all these mothers each successfully breastfed and nurtured her own daughter, who successfully grew up and did the same thing. All their sisters who failed to reach maturity and reproduce dropped out of the picture. It follows that, over millions of years, this pedigree selectively and efficiently bred for success and survival in all the essential aspects of healthy mothering.
We could imagine a similar line of paternal ancestors. We know that they all had sexual drives but their contributions to childrearing are less clearly discernible. However, it is likely that they were selected to have some satisfaction in supporting the care of their offspring, since human infants are so vulnerable. It seems biologically reasonable that those fathers who best helped their infants' mothers to rear them to maturity would have had an advantage in natural selection to be represented in the next generation. There was no biological advantage in being a mighty hunter unless you also ensured the protection and survival of your own young children and their mothers.
We may note in passing that a chimpanzee mother will surrender her infant to the care of another (related) female only as a favor to that female, and for a brief period. Our genes are 98.4% the same as those of chimpanzees and it is unlikely that the 1.6% that are different have significantly changed an activity as successfully tested as mothering.
Nature's rewards and satisfactions
I suggest it follows from the above that:
- There is arguably no occupation available today for which a woman of child-bearing age is more specifically prepared by her pedigree than that of breastfeeding, nurturing and rearing her own infant.
- There is arguably also a genetic basis for a man to derive basic satisfactions from being a father to his children, and from participating in parenting, or at least in providing security for the mother of his young children to do so.
- Nature provides pleasure, and often deep satisfaction, in doing things which are essential for survival of the species. Of these, breastfeeding and nurturing the young are, like mating, fundamental. If these satisfactions are missing, the fault is much more likely to be in the (earlier or present) environment of the mother than in her inherited biology.
- It is a logical corollary that nature - or natural selection - has, over the millions of years, favored the survival of those infants and young children who gave their mothers (primarily), and related adults in the group, enough joy and satisfaction as "rewards" to outweigh the burdens and survival handicaps involved in rearing them. Otherwise, in those conditions, they would not have done it. In a "marathon" over this length of time an inherited shortcoming in this respect would sooner or later prejudice survival, and so be eliminated.
- It further follows that if such satisfactions are lacking, then this is a matter for diagnosis and treatment. A New Zealand survey (Ritchie J & J 1970, p.43) found that as many as 40% of mothers felt that the burden of having young children outweighed or only just balanced the satisfactions and enjoyment they received. What had gone wrong? The problem probably lay in both the individual parents and in the childrearing tenets and culture of the society (See Ritchie J & J 1970; Cook 1978; see Appendix I). For example, Dr Penelope Leach argued that "our society is inimical to children" (Leach 1994, p.xiii).
- The book Children in Australian Families for secondary school students (Duffy 1995, citing Ochiltree 1990), states that "the idea that mothering is both natural and a pleasure is a myth". But if mothering is not natural - then what is?
A carrying species
Dr N. Blurton Jones studied the question of whether humans evolved as, or are by nature, one of the species of mammals that caches (i.e. hides) the infants in a safe place, returning periodically to feed them, or whether they are one of the carrying species like monkeys and apes, in which the mothers carry their infants wherever they go and feed them frequently.
He compared humans with members of caching species of mammals on the one hand, and with higher primates which are carrying species on the other. He concluded from a number of anatomical, behavioral and physiological comparisons, including the composition of the milk, that humans are indeed pre-adapted to be a carrying species. Such species breast feed their young frequently. He said that "if the implications of my comparative study are correct then the situation in which babies develop has been exceptionally constant throughout our evolution, right back into our earliest hominid phase some twenty-five million years ago and beyond throughout our entire higher primate ancestry of some forty million years". (Blurton Jones 1972).
Experiences common to infants in all of fifty diverse pre-industrial societies
What is the species-normal experience for human infants? Despite the cultural transformations which have occurred in some countries in recent millennia, and especially in recent centuries, anthropological studies of pre-industrial societies have suggested a remarkably unanimous answer.
The following emerged as universals in a large sample of tropical and semi-tropical societies. Dr Emmy Werner (1972) compared the findings of fifty cross-cultural studies of psychomotor development, from birth to two years, of contemporary groups of infants on five continents. African, Asian, Latin American and Caucasian groups were compared, and within each ethnic group "traditionally" reared rural infants showed greater motor acceleration than "Westernized" urban infants in the first six to twelve months. Moreover she found that:
"In spite of a great deal of cultural and geographical diversity, all of the infants drawn from pre-industrial communities shared certain common experiences during the first year:
- membership in an extended family system with many caretakers
- breastfeeding on demand, day and night
- constant tactile stimulation by the body of the adult caretaker who carried the infant on her back or side, and slept with him
- participation in all adult activities, with frequent sensorimotor stimulation
- lack of set routines for feeding, sleeping and toileting
- lack of restrictive clothing in a (semi) tropical climate."
It is clear from the context of breastfeeding, carrying and sleeping that the principal caretaker is normally the mother, but there are many caretakers sharing the caring.
The fact that these experiences were universal in this group of 50 pre-industrial societies, despite great cultural and geographical diversity over five continents, gives confidence that they are a guide to the normal, appropriate and presumably healthy, early experiences for infants of our species and the adult behavior which provides such experiences. Since it is in accord with the behavior of our nearest primate relatives, it shows some essentials of the early inter-personal environment in which human infants and their mothers have evolved, and which are most likely to meet their respective and mutually-complementary needs in ways which promote emotional health.
The mothers in those pre-industrial societies all had traditions and personal experiences which led them to follow these patterns, probably without consciously deliberating about what their infants' needs were. Their customs and observations of mothering were in harmony with their own intuition and their infants' promptings. Werner's observations offer a well-grounded basic guide to the needs of all human infants, since we are all the one species.
These observations were all in societies living in a tropical or semi-tropical climate and it is believed that humans evolved in warm areas of Africa. Some differences developed over more recent millennia as humans migrated to colder regions, but it seems that they continued to offer their infants most of these experiences. We may note here that Dr James Prescott analyzed a different series of studies of 49 "primitive" societies. I do not know the extent of overlap between the two series. He found that those societies in which the infant was not carried or provided with pleasurable body contact showed more violent characteristics in a number of ways. Prescott's work is outlined in chapter 8.
Some may object that all this is not relevant today because our life situations are very different. I suggest that it is reasonable, in evaluating deviations from conditions like those of our evolutionary environment, to distinguish whether or not they cut across essential, genetically-based survival mechanisms. For example, for a mother to take her child in a motor car and go to the supermarket, while being bizarre behavior in species terms, does not cut across any known survival mechanisms. It is compatible with the above pattern of infant care, in many ways that early long daycare is not.
By the standards of childrearing in many Western societies until recent decades, these patterns of infant experience may seem irrelevant, impossible, or even absurd. But they would not seem so to millions of parents in Africa and Asia, nor to the increasing numbers of mothers and fathers in Western societies, who are finding that they can, with deep satisfaction, provide many of these experiences for their own infants today. They are discovering that they can happily follow such patterns to a remarkable extent, learning that babies' wants are much the same as their needs. Examples are seen in attention to parent-baby bonding, mother-infant attunement, more flexible feeding, sleeping and toileting regimes, the increasing use of baby-carrying slings which allow body contact, and "night-time parenting" (Thevenin 1976; Cook 1978; Sears 1987). It is possible that a majority of babies in the world still have experiences like those described in pre-industrial societies.
Some advocates of early child care try to make human infant biology fit into policies which are shaped by some feminist values and economic "rationalism". For example, "Non-parental child care for preschool children is here to stay and is a form of care suited to the conditions in modern society." (Ochiltree 1994, p.116); and "In this version it is accepted that humans are still evolving and different but viable attachment patterns will emerge adapted to new pressures in the environment." (van IJzendoorn and Tavecchio 1987, cited in Ochiltree, p.69).
But humans don't evolve like that. Unless Lamarck was right in his discredited belief in the genetic inheritance of acquired characteristics, this evolution could only occur through the selective survival of such infants and a higher rate of failure to survive and reproduce among those infants less well-adapted to these "new pressures in the environment". This is a startling proposition from those concerned for infant well-being! Even if such fundamental changes were possible at all (and there are powerful reasons for doubting it) they would take many, many generations of selective breeding to achieve, with the likelihood of other (unforeseeable) consequences. Children are adaptable but within limits set by our biology. If stretched too far in ways that matter, disorders appear, first in those more vulnerable and then on a larger scale.
The ways in which Western societies have progressively departed from tribal patterns of group and social support for mothers are now well studied, together with the injustices and inequalities which have been suffered by women in many patriarchal societies. In addition, some beliefs and related attitudes and customs in Western societies have all too often been inimical to the needs of infants and young children (Cook 1978).
It is sad and perverse that many who have worked to right the wrongs done to women, have also sought to relieve women's burdens by devaluing their role as mothers and relieving them semi-permanently of their infants and young children. Child care advocates sometimes argue that the infants are being properly returned to group care with multiple carers, as in a tribe. But they ignore the fact that, uniquely in the history of our species, it is a group in a enclosed institution which does not include mother, relatives or anyone with a continuing bond or any enduring emotional commitment to that child. The consequent reduction in the possibilities for personal contact, mother-infant attunement, continuing secure attachments and tender loving care are, in practice, mostly ignored.
There is a need to study what qualities of the environment and social settings promote healthy and mutually satisfying parent-child relationships. It appears that the natural setting in which mothering behavior flourishes includes access to other supportive adults and children, some relationship to adult activities, access to the world of nature in some form, and protection from excessive stress. (Some relevant dimensions are suggested in Cook 1978, p.9).
Attachment, separation and mother-infant attunement
John Bowlby's 1951 monograph
Until recently Western society did not clearly recognize the emotional importance of the early mother-child relationship, but in 1951 the World Health Organization published Maternal Care and Mental Health by Dr John Bowlby. This landmark review of the seriously damaging consequences which maternal and social deprivation can have on the development of infants and young children was an important milestone. It triggered much debate, research, social change and revision of child development theory.
Since 1951 the world has been on notice that total early separation and deprivation of the care which mothers normally provide can have serious consequences. Bowlby went on, through ethological, cross-cultural and psychological studies, to develop his major contributions in his three-volume work Attachment and Loss (Bowlby 1969; 1973; 1981). Yet some advocates of early day care have sought to dismiss any relevance of this work to long day care, describing it as "Bowlbyism" (Oakley 1981, cited in Ochiltree 1984, p 8).
Bowlby studied natural sciences and psychology at Cambridge and worked in a school for maladjusted children during his medical training before becoming a psychoanalyst in 1937. He realized that major separations from parents were significant early experiences that could be positively verified, and so give a solid basis for research into the importance of early experiences in psychological development. He concluded that the first task for theory was to understand the nature of the child's tie to his mother (Bowlby 1980, p.7).
Learning from animal behavior: attachment
In 1951 Bowlby learned that in some animal species such as ducks and geese "a strong bond to an individual mother-figure could develop rapidly during a sensitive phase of early life and that it tended to endure" (Bowlby 1980, p. 8). He learned of such patterns in other species, and heard that young monkeys being raised without their mothers in depriving circumstances showed many behavior patterns like those of young children raised in institutions. He realized that ethology, which is the scientific study of the behavior of animals (including humans), might shed light on the emotional and behavioral disturbances which he had reviewed in his 1951 monograph and seen in his work with disturbed children.
This involved understanding that the genetic inheritance with which each living creature begins life is the outcome of a long process of natural selection. Those characteristics which bring an advantage for surviving in the environment at the time are more likely to be passed on to later generations. The survival of mammals, as animals which breastfeed their young, depends on keeping the mother and her young together, both for protection and for nourishment. Grazing animals must, from birth, be able to follow their mothers, as they move on. This requires inherited and automatic mechanisms since the matter is too urgent to be left to the uncertainties of learning. But the babies of higher primates, such as chimpanzees and humans, for some time after their births are too immature to follow their mothers and must be held and carried. Baby monkeys and apes hang on in front, and when older they ride on their mothers' backs. Bowlby used the term attachment for this tie or bond, and attachment behavior for those behaviors that keep the young near the mother.
Owing to the size and rapid growth of the human brain, babies must be born at a stage of maturity when other mammals would remain safely in the uterus, in an environment that is normally secure. There are reasons for suggesting that for as long as nine months humans can be regarded as continuing the period of gestation, but outside the womb - as "exterogestates" undergoing exterior gestation (Bostock 1958). This pattern is seen in marsupials, such as kangaroos and koalas, but they have the convenience of a pouch supplied with a nipple.
Because of this human helplessness mother-infant attachment is needed from birth, long before the baby develops true infant-to-mother attachment. During this time babies like to be held and carried, and Liedloff (1975) described this as the "in-arms" stage of human development. A baby can do little to overcome a potentially dangerous separation except cry, and then reward the parents by showing appreciation, and later affection, when they respond.
It is now known that from the time of birth there is much more going on between new babies and their mothers than was imagined until the 1970s. While the mother-infant attachment or bonding side of this interaction has become familiar, the active role of the baby in this two-way process is less well known.
Research since the 1970's has supported Bowlby's view that the new baby has innate social capacities. Studies have shown that an (unsedated) newborn baby can see, hear and move in rhythm to his mother's voice "in the first minutes and hours of life resulting in a beautiful linking of the reactions of the two and a synchronized dance between mother and infant" (Klaus & Kennell 1976). From soon after birth babies show a preference for their own mother's voice and the smell of her milk. They prefer a human face to other shapes and can distinguish certain emotions.
Thus a baby is innately equipped to encourage a communicating relationship, and encourage her mother to fall in love with, or become crazy about her baby, though this does not always happen. Many fathers, too, have been surprised by how thrilled they feel when their new baby gazes into their eyes, and the excitement of caring for this real little person seizes them and they become "engrossed".
Frame-by-frame analysis of film and video-recordings, pioneered since 1971 by Dr Daniel N. Stern, have shown that a kind of micro-world of intricate behavioral communication develops as a mother and baby get to know each other. Mothers too, appear to be innately equipped to sense these cues, and sensitive, responsive mothering is normally rewarded by a remarkable "attunement" of playful two-way synchronized interactions which have been described as a "dance", each responding to the cues of the other. Positive interactions bring joy and delight, but the details of less positive reactions to mismatch and disharmony, such as turning away, are also clearly shown by babies (Stern 1985). This "astonishing attunement" in the healthy mother-infant relationship is a facet of nature's health-promoting processes.
Thus the infant "is given both an innate general repertoire of these behaviors to perform and the mechanisms to decode their performance in others" (Stern 1995, p.65). These "micro-events" which last split-seconds, are "the basic steps of an interactive regulatory process" to regulate the level of feeling and activity occurring between mother and infant. Through them the infant gives cues to her mother to guide her to match the infant's developmental needs, and these processes occur in feeding and other activities. Soon the infant not only responds to, but actively seeks to modify, the adult's behavior. As the mother communes with her baby she appears to be giving her infant "a sense of being appreciated, validated, and approved, which seems to be such a vital need at this time of life" (Karen 1994, p.351; see also Thoman & Browder 1988).
Research has shown that well-synchronized mother-infant interactions predict secure infant-mother attachment and this is important (Isabella & Belsky 1991). It seems that maternal sensitivity does "promote security by fostering trust. That trust, then, forms the foundation for the babies secure attachment to the mother." (Steinberg & Meyer 1988).
This process may develop in less healthy ways. If the mother is insensitive to the baby's cues, perhaps being over-controlling, or too stimulating, the baby may after a time develop protective ways to avoid such stresses. If mother is unwell or depressed she may be unable to respond and such situations may need help (see Stern 1995), but our purpose here is to understand the healthy pattern. It is not surprising that, as shown in chapter 5, long day child care may have a disruptive influence on infant-mother attunement.
The balance between exploration and attachment
As they become mobile, human infants explore the world from the secure base of the mother or some familiar adult, keeping an eye on where mother is, so that they can scurry back to her as a haven of safety if they sense a threat of danger. In this way the healthy drive to exploration behavior which might lead a toddler into danger is normally held in balance by attachment behavior. The child's perception of any risks, or their absence, will determine which urge prevails (see Ainsworth & Bowlby 1991). An enterprising researcher wrote a neat paper describing such behavior by toddlers in a London park, and it is easy to observe (Anderson 1972).
If the toddler is unable to locate mother this is cause for alarm, and other activities are suspended until she is found. Failure to locate mother is valid grounds for fear, and the separation now activates in-built behavioral systems which are part of nature's survival equipment, "designed" to bring mother and child safely together again.
If an infant is afraid that mother will disappear he may try to prevent this by clinging behavior. If a mother tries to stop this clinging by punishment or by pushing the infant away this may add to his reasons for anxiety. The child's in-built response to fear is to cling more closely, and this can lead to a vicious circle of rejection by the mother, leading to more clinging by the infant.
Multiple attachment figures
Though he is sometimes misrepresented, Bowlby specifically denied ever saying that mothering should always be provided by the natural mother or that mothering cannot safely be distributed among several figures (Bowlby 1969, p.303). As the first year progresses into the second, infants may have several attachment figures, usually including father, siblings and grandparents, depending on who has cared for them. In non-parental child care they develop attachments to care-givers if the care is sensitive and favorable. However there is an hierarchy of preferences, and mother is usually the preferred and principal attachment figure, if she is available.
Infants' reactions to major separations
Bowlby worked with James Robertson who, with his wife Joyce, played a major role in reforming the care of children in hospitals throughout the world (Robertson J & J 1989). By observing and filming children in the second and early third year of life while they were undergoing complete separation from their mothers and other attachment figures, Robertson saw that, unless young children were receiving responsive substitute mothering, they typically went through three successive stages which he termed protest, despair, and finally detachment.
Bowlby described how it was found that if a child between the ages of about twelve months and three years is removed from his mother-figure to whom he is attached and placed with strangers in a strange place, "his initial response ... is one of protest and of urgent effort to recover his lost mother. 'He will often cry loudly, shake his cot, throw himself about, and look eagerly towards any sight or sound which might prove to be his missing mother.' This may with ups and downs continue for a week or more. Throughout it the child seems buoyed up in his efforts by the hope and expectation that his mother will return.
"Sooner or later, however, despair sets in. The longing for mother does not diminish, but the hope of its being realized fades. Ultimately the restless noisy demands cease: he becomes apathetic and withdrawn, a despair broken only perhaps by an intermittent and monotonous wail. He is in a state of unutterable misery." (Bowlby 1981, p.9). Bowlby termed this a state of grief and described how, although the child is quieter and less explicit in his communications, his behavior and words show an orientation to the lost mother which may become disguised but it is persistent. This longing for the mother "is often suffused with intense, generalized hostility" (Ibid p.13).
After discussing the relationship of this to mourning, Bowlby described how, after a week or more out of his mother's care and without being specially cared for by an assigned substitute, the phase of detachment develops, with "an almost complete absence of attachment behavior when he first meets his mother again." (1981, p.20). At this stage the child can be superficially cheerful and friendly to almost anyone, except to his mother if she reappears. Staff in hospitals and residential nurseries used to look forward to this stage, saying that the child had "settled", so parental visits were sometimes discouraged to avoid "upsetting" the child by reactivating his overt protests.
Earlier this stage was called one of denial, since it appeared that the child could no longer bear the anguish of loss of the one he loved most, and a psychological mechanism of denial had supervened as a protection against continuing emotional pain. Clearly, this is a disordered and unhealthy state to develop in an infant's love life. The basic trust which a healthy infant normally develops in his mother seems to have been blocked. Smaller elements of blocking of attachment longings can be seen following much briefer separations than those leading to the fully developed state of detachment (for example, see Harsman's study in chapter 5).
Children vary and the longer-term consequences of separation are also influenced by what happens subsequently. Bowlby regarded detachment as a psychological defensive exclusion process, and it occurs in mourning. An important matter for future mental health was whether this process was reversible, but he said that "In infants and children, it appears, defensive processes once set in motion are apt to stabilize and persist" (1981, p.21). He described how these defensive processes may be seen in adult patients who have suffered early separations. "As a result the desires, thoughts and feelings that are part and parcel of attachment behavior become absent from awareness" despite the patient's wishes to the contrary (Bowlby 1980, p.19). It seemed that the behavioral systems governing attachment behavior had become de-activated and remained so.
The significance of attachment experiences for human personality development
Unraveling the relationship of attachment experiences to personality development was a major part of Bowlby's life work. Much research has been done using the theories that he developed and some of this is discussed in chapter 4.
The last eleven chapters of Bowlby's trilogy were concerned with the mourning of children. He concluded the Epilogue to the last volume of Attachment and Loss by saying: "Intimate attachments to other human beings are the hub around which a person's life revolves, not only when he is an infant or a toddler or a schoolchild but throughout his adolescence and his years of maturity as well, and on into old age. From these intimate attachments a person draws his strength and enjoyment of life and, through what he contributes, he gives strength and enjoyment to others. These are matters about which current science and traditional wisdom are at one." (Bowlby 1981, p. 442).
Relevance to child care?
The big question for long day care for infants and young children is: to what extent does this knowledge about attachment reactions to major separations apply to those separations which occur for most of the waking hours during most days of the week? To what extent are "caregivers" adequate secondary attachment figures or adequate substitutes for the principle attachment figure, ideally or in practice?
Are the reactions documented by Harsman (1994), and described in chapter 5, less dramatic, "micro" examples of similar processes, and if so what consequences do they have for optimal human development? Observing Swedish children for five months after starting day care at ages of 6 to 12 months, she reported that "52% showed a negative change in mood during the initial period and they were assessed as sad and depressed in the day-care setting." Two or three of these infants "reacted in line with the classical phases of 'protest and despair' "(Italics inserted). In the history of medicine the fully developed forms of a disorder are described first. After this classical picture has become familiar then milder forms and variations start to be recognized.
Dr. Mary Ainsworth built upon Bowlby's work in her studies of mother-infant relationships, and she developed a method for assessing the quality of the infant-mother side of the attachment relationship. This Strange Situation assessment, carried out sometime between 12 and 20 months and taking only 20 to 25 minutes, is based on detailed observation of how an infant reacts when reunited with his mother after two brief experimental separations under controlled conditions. It has proved a remarkable instrument which has led to much productive research, particularly in studying outcomes of early day care. It is described in chapter four.
In his book Becoming Attached: Unfolding the Mystery of the Infant-Mother Bond and its Impact on Later Life, Robert Karen (1994) gives an authoritative, readable account of the development of the theories, research and controversies arising out of the pioneering work of John Bowlby, James Robertson, Mary Ainsworth and many others involved in this crucial area of child development. Many of these pioneers were interviewed by Karen in preparing his book. Academic reviews of theory and evidence relating to attachment may be found in Belsky & Cassidy (1994) and Rutter (1995).
This article is Chapter 1 in Early Child Care: Infants & Nations at Risk. Excerpted with permission of the author.
Dr. Peter S. Cook is a retired Sydney, Australia child and family psychiatrist, who writes on preventive child and family mental health. He is the author of Early Child Care: Infants and Nations at Risk (Melbourne: News Weekly Books, 1997).