The Nature of Nurture has several goals. The first is to challenge long-standing views of how childhood experience, whether adverse or supportive, shapes children’s short and longer-term development. Toward this end, it shows how standard developmental theories, models and ways of thinking idealize and romanticize the very nature of development, presuming that nature intended humans to become, among other things, secure, autonomous, industrious, friendly, intimate, achievement striving and caring for the next generation. In addition to presuming that such so-called “optimal” ways of developing are fostered by supportive and nurturing early environments, traditional thinking contends that adverse childhood experiences, commonly known as “ACES”, promotes the opposite, ways which are routinely characterized as evidence of dysfunction, dysregulation and disorder. 

The second goal is to view how—and why—early-life shapes later life upon putting on evolutionary lenses. In so doing, it makes clear that almost all discourse about nature and nurture only focuses on genetics when it comes to the nature side of things, ignoring natural selection, adaptation, and the fundamental goal of all living things, which is to make more life by passing on one’s genes. To evaluate the validity of this alternative way of thinking the book tells the story of the development and testing of a novel prediction that standard developmental thinking never would advance and couldn’t explain should it prove empirically robust, as it has. And that is that early-life adversity accelerates sexual development, operationalized in terms of pubertal maturation, as this would increase the chances of the developing person being able to pass on their genes before becoming developmentally compromised or, worse, dying. In other words, evolution has shaped development to respond to adversity in adaptive ways, even if these ways are not in line with modern Western values, like being kind, deferring sexual behavior, being devoted to one or a few intimate partners, and being a nurturing parent. 

The third goal The Nature of Nurture is to qualify what has just been stipulated by making it clear that, again for evolutionary reasons, children should vary in their developmental plasticity, with some more and others less susceptible to being shaped by their childhoods. The logic here, also supported by extensive evidence, is that the future can prove inconsistent with the past, so instead of childhood preparing the child for his/her anticipated future life, it could result in a mismatch, thereby undermining the prospect of realizing evolution’s ultimate goal. And this is because the future is inherently uncertain, so it is impossible to know in advance, whether childhood will well prepare children to succeed in their tomorrow or not. 

While the book challenges many prevailing ideas, when it comes to implications and applications of an evolutionary mindset, the baby is not thrown out with the bathwater. Places where evolutionary insights prove in line with more standard ways of thinking, as well as where they differ, are made clear. 

The core insight of the book is that when it comes to thinking about nature and nurture with regard to child development--and especially the effects of early life on later development-- evolutionary ideas have been ignored while genetics has been singularly heralded. But when you consider natural selection, adaptation, and the goal of all life to make new life, understanding of why and how childhood does—and does not—influence later development, it becomes apparent how prevailing thinking about these issues has been distorted to align with modern Western values, not evolution. This is the reason why the timing of sexual maturation and thus pubertal timing proves so important, along with ideas of variation across children in their susceptibility to effects of environmental experience, play such critical roles in the ideas advanced. These have guided a small group of developmental scholars to test new ideas and discover new things, ones which remain widely underappreciated by parents, service providers, and policy-makers alike. What is made explicit through the book is that it does not embrace the idea that “biology is destiny”, which is a frequent but mistaken assumption when evolution is discussed. In fact, as the book also spends substantial time addressing the issue of genetic influence, it results in the conclusion, true of natural selection itself, that “the genome proposes and the environment disposes”!

Ongoing thread. More from Jay Belsky to follow.