The Environment of Evolutionary Adaptedness

“Nothing in biology makes sense except for in the light of evolution.” This famous quote from Theodosius Dobzhansky illustrates my feelings towards the utility of evolution for understanding children and youth. Certainly, genes without environment are nothing. But the environment must act on a child through the expression of that child’s genes. Genes that were shaped by evolution.

But that shaping happened thousands, if not millions, of years ago. Evolution acts to solve today’s problems tomorrow. For example, our inherited sweet/fat/salty cravings were presumably of great help to our ancestors, even if they are no longer very helpful in modern Western society. So one of my keen interests is trying to better understand the past conditions that led to our current genes. These past conditions, that include evolutionary pressures from many different times and locations, are generally summarized under the umbrella of the Environment of Evolutionary Adaptedness, or EEA. If we can better understand the EEA, we can better understand the reasons why our mind/genes work the way that they do.

I am currently work on several projects regarding the EEA and childhood. The first has to do with infant and child mortality. In a survey of dozens of hunter-gatherer and historical cultures, there is a remarkable consistency in the infant and child mortality rates. Roughly 1/4 of all infants and HALF of all children died in the past! This is a tremendously important factor for anyone interested in the evolution of our species. From my perspective, these high levels of mortality mean that it really matters for children to be adapted to childhood. In other words, children aren’t just incomplete adults- they are adapted to thriving and surviving each of the stages of childhood that they must pass through. This idea is largely the foundation of evolutionary developmental psychology, where the prevailing sentiment is that children are adapted to being children- youth is not wasted on the young!

The second project examines the EEA from historical, anthropological, archaeological, paleo-, and demographic perspectives in order to better understand the link between harsh environments and pubertal development and reproductive strategies. What I found, across disciplines, was consistent evidence showing that in harsher or less predictable environments, our human ancestors delayed pubertal development and had fewer offspring than individuals living in relatively more benign and plentiful environments. This casts strong doubt on current “fast-slow” models of development that hypothesizes faster pubertal development in harsh environments as a way of avoiding mortality outcomes.

The third project has to do with breastfeeding. What struck me about human breastfeeding is that it is not intuitive. Indeed, it can be extremely difficult for some women to succeed at with their infant. This is in part due to the fact that the physical design of the human breast appears to require a more complicated sucking action than other mammalian breasts. But it’s also due to the fact that the correct technique for feeding an infant is not instinctive for mothers. It has to be learned, or taught. What does this tell us about the human EEA? To me, it very strongly suggests that since breastfeeding is absolutely vital for infant survival (see previous point!), mothers must have had ample, reliable opportunities to learn and/or be taught the correct way to breastfeed their infant. This means that women must have lived in stable, cooperative groups for most, if not all, of our evolutionary history.

Researchers at Brock

There are many exciting research projects involving evolution and human behavior here at Brock University. The following is a list of researchers at Brock who are either currently involved or interested in human evolutionary research.

Dr. Naomi Andrews – Dr. Andrews studies adolescent social relationships as well as at-risk mothers.

Dr. Michael Ashton – Dr. Ashton is currently the chair of the department of psychology. Dr. Ashton studies the adaptive nature of human personality, and has co-developed a new personality measure, the HEXACO, that reflects his evolutionary perspective.

Dr. Tony Bogaert – Dr. Bogaert studies patterns of human sexuality, including sexual orientation, pornography, risky sexual behavior, and sexual offending.

Dr. Angela Book – Dr. Book studies the adaptive and personality aspects of psycopathy at Brock University. She is currently examining the concept of psychopathy and its theoretical validity.

Dr. Andrew Dane – Dr. Dane is a clinically-trained psychologist at Brock University, who is interested in developing interventions for children who are bullies and or victims.

Dr. Ann Farrell – Dr. Farrell studies adolescent aggression and bullying from a bioecological perspective that emphasizes the importance of broader social and cultural factors.

Dr. Cheryl McCormick – Dr. McCormick is a Canada Research Chair who studies environmental stressors from a neurological point of view. Recently she has done evolutionary research on facial cues and aggression.

Dr. Liz Shulman – Dr. Shulman studies adolescent risk taking behaviors and decision making. She is interested in theoretical and policy outcomes.