Anthropologist and primatologist Sarah Blaffer Hrdy (2000), in her book Mother Nature: Maternal Instincts and How They Shape the Human Species, theorizes that survival of human infants not only depends on traditionally cited factors such as availability of resources, but also on being born “sufficiently attractive” – that is, fit, appearing healthy, and with vitality – especially for early humankind, from the Stone Age to before the advent of modern medicine. Patterns in infant attachment and human development, the subjects of this essay, then, could be said to be broadly impacted by variances in culture and tradition across civilizations around the world.  Attachment on the part of the infant involves “not just attaching to mother but appealing to her," a survival strategy key to an otherwise entirely helpless individual.   Concurrently, motherhood involves investment of energy and resources, encouraging dual-parenting and other strategies that, in turn, affect the individual’s development through adulthood.  The cultural and traditional variability in parenting strategies across the world indicate that no universal ‘correct’ approach is applicable to the human experience, but, rather, that the “construction of ‘mother love’” had its roots in culture, and “with the involvement of innate mechanisms.” As a result, the study of evolutionary biology has a lot to contribute to the understanding of motherhood, infant attachment, and human emotional development.

Hrdy writes that resources, culture and circumstances are determining factors for mothers and the survival of newborn children.  Those “children whose mothers draw back emotionally often fail to thrive” and notes that in high-risk populations, such as one in Santiago, Chile studied by ethnographers, very high rates of abnormal weight gain and even, in rare cases infanticide, correlate with children that are not as “securely attached” as others.  And on the other end of the spectrum, in rich Western nations, crying babies are often ignored until they quiet down, another regular meal to arrive in time.  “Still and all, under duress, infants do well to toe a fine line between signaling their distress and appearing too needy,” as evolution has fine-tuned this behavior for the repercussions of, for example, sickliness.  This evidence further erodes the traditional and binary ‘nature vs. nurture’ discussion surrounding infant attachment and development and adds salience to the idea that evolutionary biology can inform individuals about human parenting strategies.  Other areas of strategy including wet nursing and alloparenting, also with roots in humans’ evolutionary past, are further discussed by Hrdy in the chapter “Old Tradeoffs, New Contexts” illuminating on approaches to age-old parenting challenges as they have themselves evolved throughout human history.

As already mentioned, successful attachment and parenting strategies are key for the holistic development of emotional capacity as children grow into adulthood.  Envisioning early hunter-gather societies, Hrdy speculates that these “parental effects” contributing to emotional health would have been crucial to survival in such stark environs in which many early hominids prospered. Nevertheless, because of the huge array of cultural differences that exist across human societies, it has proven difficult to scientifically test how human personality and emotion has been shaped by evolution and natural selection.  Some evidence from recent studies of caterpillar development indicate that different “morphs” appear in response to resource-availability scenarios, elucidating on some of the ways that social scientists, studying prehistoric human lifeways, have started to approach emotional development from an evolutionary perspective. Hrdy posits, rather positively, that “the circumstances that signal a developing human organism that it will be worthwhile to grow up caring about what happens to others” have been selective factors in human personality development, strongly linking empathy and compassion to what it has always meant to be human.

References

Hrdy, S. Mother Nature: Maternal Instincts and How They Shape the Human Species. New York. Ballantine Books. 2000.