by Dr Emily Emmott (see profile)
Humans as Communal Breeders
When we think back to the important people who shaped us through our lives, many of us will think about a parent or parents. But many of us will also think about step-parents, grandparents, siblings, teachers, friends, and more. The fact that we are supported by many people throughout our childhood is very unusual: In non-human mammals, care for juveniles are typically and solely provided by the biological mother. Only 9-10% of mammals display parental care, where biological fathers are additionally involved in raising offspring without the support of other helpers. Humans go beyond parenting, with many allomothers ("other mothers") contributing to childrearing.
In fact, evolutionary anthropologists have argued that humans evolved as cooperative/communal breeders, where reproduction and child survival is contingent on allomaternal support. This is likely to be both a cause and consequence of our unusual life-history, which involves a “premature” birth of infants (who are essentially helpless for a good few years), followed by an extended childhood and adolescence. Essentially, human children are very "expensive" to raise, and mothers cannot do it alone!
Infancy is a particularly expensive time for mothers due to breastfeeding. Exclusive breastfeeding is estimated to require 450–700 kcals a day. This often goes hand-in-hand with prolonged infant carrying, which can be as energetically expensive as breastfeeding itself. On top of these energetic costs, breastfeeding conflicts with other maternal activities (particularly maternal labour and production activities), leading to high opportunity costs. From an evolutionary perspective, we therefore hypothesise that breastfeeding is a crucial maternal investment activity that is only possible through extensive support from a range of allomothers.
Recognise humans as communal breeders to support breastfeeding, even in the 21st century
As an evolutionary anthropologist, that idea that we need extensive support to breastfeed is a given. However, this is far from being universally acknowledged. Across developed populations, childrearing practices and culture has gradually shifted from communal care to intensive parenting. This is reflected in society at different levels, including interventions and policies around breastfeeding support, which tends to exclusively target the mother while disregarding wider support.
The consequence of this may be significant, particularly given the known benefits of breast milk for infant and maternal health. The UK has one of the lowest breastfeeding rates in the world, with around 1% of women achieving the WHO recommendation of exclusively breastfeeding for 6 months. While major public health effort has been put into improving breastfeeding rates in the UK, improvements in breastfeeding duration has been minimal at population level, and many randomised control trials on breastfeeding support have been ineffective.
We suspect this may partly be due to targeting support on the mother, without acknowledging the wider allomaternal network - which undoubtedly influences breastfeeding. Involving fathers and grandparents in breastfeeding interventions and support programmes, for example, may help create and reinforce a supportive network of allomothers around mothers and infants. Our own study shows that UK mothers who receive extensive support from a range of people are more likely to breastfeed for longer.
This is important to get right. In the UK, most women start breastfeeding hoping to breastfeed long-term, but reluctantly stop in the first few weeks or months due to various challenges and difficulties. This is often accompanied by an acute sense of guilt and failure. But evolutionary theory tells us trying to do it alone is impossible, and many women are being set up to fail. To support women achieve their breastfeeding goals, as a public health community, we may need to reach wider beyond mothers.
Further reading:
Emmott, E. H., Page, A. E., & Myers, S. (2020). Typologies of postnatal support and breastfeeding at two months in the UK. Social Science & Medicine, 112791. https://doi.org/10.1016/j.socscimed.2020.112791
Emmott, E. H. (2020). Typologies of postnatal support and breastfeeding at two months in the UK: Response to comments by Harpur & Haddon. Social Science & Medicine, 112944. https://doi.org/10.1016/j.socscimed.2020.112944
Emmott E.H.,Page A.E. (2019) Alloparenting. In: Shackelford T., Weekes-Shackelford V.(eds) Encyclopedia of Evolutionary Psychological Science. Springer,Cham. DOI: https://doi.org/10.1007/978-3-319-16999-6_2253-1 (Available for free online: https://doi.org/10.31219/osf.io/mcpv2)