From intelligence to emotion, for centuries science has told us that men and women are fundamentally different. But this is not the whole story.
In her new book, Inferior, award-winning science journalist and author Angela Saini sheds light on controversial research and investigates the ferocious gender wars in biology, psychology and anthropology, while taking readers on an eye-opening journey to uncover how women are being rediscovered. She explores what these revelations mean for us as individuals and as a society, revealing an alternative view of science in which women are included, rather than excluded. Here’s an excerpt from the book:
‘We see a huge range of plasticity in how much engagement there is in human males.’
Sarah Hrdy tells me that when she welcomed her first grandchild last year, she took the opportunity to run a small experiment on her family. Arriving at her daughter’s house, she took saliva samples from herself and her husband. She took another set after they had spent some time with the new baby. Analysis of these samples revealed that they had both experienced a rise in oxytocin, the hormone associated with love and maternal attachment.
Our bodies betray how strong the emotional connections can be between children and people who aren’t their parents. Physical contact with a baby, scientists have long known, can have dramatic effects on a mother’s hormone levels. These hormones in turn influence how she bonds with her child. Others who aren’t mothers, we now know, can experience these hormonal changes too.
In the past, evolutionary biologists often assumed that, of all the people providing support to mothers, fathers would have been front and centre. In his 2006 book Men: An Evolutionary and Life History, Richard Bribiescas suggests exactly this. And from the perspective of how we’ve lived for centuries, often in monogamous marriages and nuclear families, this seems to make sense. Even if they weren’t directly involved in childcare, the material help that fathers brought to families, such as food, must have been crucial to keeping children alive and thriving.
Some recent studies, however, don’t agree. In a 2011 paper in Population and Development Review, Rebecca Sear at the London School of Hygiene and Tropical Medicine and David Coall at Edith Cowan University in Western Australia pulled together all the published studies they could find on how the presence of fathers, grandparents and siblings affects a child’s survival. They found that other family members were so valuable that, once a child passed the age of two, they could even cushion the impact of an absent mother. Where this help came from, though, was more of a surprise. Older siblings had a more positive effect than anyone besides the mother. After this came grandmothers, then fathers. ‘Fathers were rather less important: in just over a third of all cases did they improve child survival,’ Sear and Coall note. (Grandfathers followed far behind all other family members.)
This doesn’t mean that hands-on fathering isn’t important. Just that it isn’t always there. In 2009 anthropologist Martin Muller at the University of New Mexico and his colleagues studied how much effort men in two neighbouring but different East African communities put into parenting. In one, the Hadza hunter-gatherers, they found that fathers were involved in everything from cleaning to feeding infants, spending more than a fifth of their time interacting with children under three if they were in the camp, and also sleeping close to them. In the other, a pastoralist and warrior society called the Datoga, they found a strong cultural belief that looking after children was women’s work, with men eating and sleeping separately and not interacting much with infants. The men’s hormone levels reflected the difference in parenting styles. The more involved fathers – the Hadza – produced less testosterone than Datoga fathers.
‘We see a huge range of plasticity in how much engagement there is in human males,’ says Richard Bribiescas. ‘So you can be the most doting and caring father, and everything is great and lovely, to a father that’s sort of engaged and maybe just brings food and resources home, to the ultimate, very horrific cases of things like infanticide.’ If society expects men to be involved in childcare, they are, and they can do it well. If society expects them to be hands-off , they can do that too. This plasticity is unique to humans. ‘In other great apes and other primates you simply don’t see that. They’re locked into one strategy,’ says Bribiescas.
If, in our evolutionary history, caring for children is something that would have been done not just by mothers, but also by fathers, siblings, grandmothers and others, the traditional portrait we have of family life starts to crack. A nuclear family with one hands-on father certainly isn’t the norm everywhere. There are a few societies, for example, in which children have more than one ‘father’. In Amazonian South America there are communities that accept affairs outside marriage and hold a belief that if a woman has sex with more than one man in the run-up to her pregnancy, all of their sperm helps build the foetus. This is known by academics as ‘partible paternity’. Anthropologists Robert Walker and Mark Flinn at the University of Missouri and Kim Hill at Arizona State University, who have confirmed how common partible paternity is in the region, claim that children benefit from these kinds of family arrangements. With more fathers, their odds of survival go up. They have more resources and better protection from violence.
This all points to the possibility that living arrangements among early humans could have taken any number of permutations. Monogamy may not have been the rule. Women, if they weren’t tied to their children all the time, would have been free to go out to get food, and perhaps even to hunt. The Victorian ideal that Charles Darwin based his understanding of women upon – mother at home, taking care of the children, hungrily waiting for father to bring home the bacon – is left out in the cold.
(Excerpted with permission from Inferior: How Science Got Women Wrong and The New Research That’s Rewriting The Story by Angela Saini. Buy it here: http://amzn.to/2tnQ3mE)