What role has aggression played in human evolution? Can scientists predict who might be more aggressive? And how might increased aggressiveness be linked to overall fitness? Previous research has found that aggression in hockey players is correlated with their facial width to height ratio (fWHR), and a new study builds on this work by demonstrating that fWHR may also predict a soldier's military rank and how many children he fathers. Below the jump, the authors of this latest study – primarily John Loehr – discuss their work.
Like many people, I read the interesting 2008 study that investigated the relationship between aggression and facial structure in hockey players [doi:10.1098/rspb.2008.0873]. In this study, co-authors Justin Carré and Cheryl McCormick combined psychological testing and real-life data collected during varsity and professional NHL hockey players' careers to demonstrate that there is a connection between aggression in men and their fWHR.
The fWHR consists of two standard measurements used by anthropologists to measure skulls, but the breakthrough that accounts for the current interest in fWHR was the idea that this measurement can also be made (albeit approximately) from a photograph (see right; doi:10.1098/rspb.2008.0873). This makes fWHR special because evolutionary psychologists are not only able to use it to test hypotheses in the lab, but they can also use it to analyse human behaviour in real life situations – in corporate boardrooms [doi:10.1177/0956797611418838], in sports [i.e.; doi:10.1098/rsbl.2013.0140] and even using forensic statistics [doi:10.1016/j.evolhumbehav.2012.02.002]. Studies of the human face have long been done using qualitative scores, in which judges rate faces on subjects' dominance, beauty or masculinity, etc. fWHR provides a quantitative measure, thus removing subjective opinions from the equation.
Read more at The Guardian
