We vary from one another in lots of ways. In the behavioral sciences, we refer to this fact as “the science of individual differences.” From an evolutionary perspective, a large-scale way to differentiate behavioral patterns among people is found in “life history strategy”—focusing on whether we see our lives as likely to be “fast” (leading to various short-term behavioral strategies) or as “slow” (leading to a variety of long-term strategies).
The Emergency Room in New Hampshire in 2006
When our kids were little, my wife and I took them up to New Hampshire for a weekend, planning to spend time in the coastal region where we had met years prior. We got to the hotel late—maybe around 10:30 p.m. The plan was that my wife would get things set up and I would go out to our favorite restaurant from our graduate school days, Taste of India, and bring back take-out. About a half hour later I was back at the hotel, only to find my wife and kids in distress in the parking lot. Apparently our then-2-year-old son, Andrew, had decided that it would be fun to bounce from one bed to the cot to the dresser—head first.
We quickly found ourselves in the ER. And while we were waiting for the doctor to come in and give Andrew stitches (it would be six in total), with me pretending that everything was alright, we overheard some older male in the hallway. This was 11 p.m. on a Friday night.
Multiple police officers were escorting a young guy—I’d say he was about 22—down the hallway outside our hospital room. He was bleeding and swearing up a storm. A female friend of his was trying to calm him down.
“I’ll kill that guy! I’ll f’n kill him!” the guy cried, blood dripping everywhere…
Young Male Syndrome Defined
So here we’ve got two males in the ER on a Friday night in coastal New Hampshire. My then-2-year-old son, who (luckily?) only needed six stitches, and some young guy who had gotten into a bar fight that led to excessive bleeding—and a police escort to boot.
If you follow the work of evolutionary social psychologists, you’ll see that young males are, in many ways, part of an at-risk population. Across the entirety of the lifespan (especially during the younger years), males are more likely to die than are females—an outcome that largely is rooted in excessive risky behavior and a long evolutionary history of physical competition that is found disproportionately among males (see Kruger & Nesse, 2006).
This general phenomenon has been termed Young Male Syndrome (see Wilson & Daly, 1985). Based on what I saw with my son on that night, I started wondering whether Very Young Male Syndrome is a thing as well.
Maleness, Life History, Environment, Injury, and Sex
Along with the other members of an awesome team of evolutionary behavioral scientists (Johnsen, Kruger, Geher, Shaiber, Garcia, & Wiegand, 2017), Laura Johnsen and I designed a study to explore the gender-based, developmental, and environmental factors associated with childhood injuries. Our main prediction was the males would be more at-risk for childhood injuries than females would be—and that this phenomenon would be exacerbated by poor neighborhood conditions. Further, based on the broad elements of life history strategy, we predicted that such injuries would be predictive of markers of adolescent sexuality.
Our results were revealing. Being male was strongly predictive of lots of things related to childhood injuries. Males were more likely than were females to report having had significant injuries during childhood—and these injuries were more likely to (a) be severe and to (b) require stitches. Males were also more likely than were females to report that their injuries were “outside of their control.”
And get this: The total number of stitches one received during such an injury was predictive of one’s total number of sex partners later in life.
Further, one’s overall life history strategy was significantly related to
Across the lifespan, males (compared with females) are more likely to have experienced physical injury and death. This phenomenon may be partly due to the fact that males generally demonstrate a “faster” life history strategy than do females. And life history strategy, which varies reliably across people, plays a substantial role across a variety of behavioral domains.
Maleness, youth, and unsafe environmental conditions, then, seem to, in combination, lead to an approach to life that puts one on a faster behavioral track—a track that is often fraught with physical and psychological risk.
Ever wonder “what’s up with young males”? The evolutionary perspective on behavior can help us understand this long-standing human issue.
Figueredo, A.J., Vásquez, G., Brumbach, B.H., Sefcek, J.A., Kirsner, B.R., & Jacobs, W.
(2005). The K-Factor: Individual differences in life history strategy. Personality and Individual Differences, 39(8), 1349-1360.
Johnsen, L.L., Kruger, D.J., Geher, G., Wiegand, A.G., Shaiber, R.L., & Garcia, J.R. (2017). Youth injuries as a function of sex, life history, and neighborhood safety. Human Ethology Bulletin, 3, 85-108.
Kruger DJ, Nesse RM: An evolutionary life history understanding of sex differences in human mortality rates. Human Nature,74 (1): 74-97, 2006.
Wilson, M. and Daly, M. (1985). Competitiveness, risk taking, and violence: the young male syndrome, Ethology and Sociobiology, 6, 1, 59-73.