Talking about catchy titles, here is one that caught my eye. Carre and McCormick studied the association of facial width-to-height ratio with aggressiveness in a random sample of students and (Canadian) hockey players. They found out that there is sexual dimorphism in the facial metrics, and that men with higher facial width-to-height ratios show more aggressive behaviour.
High possibility of bias in the measurements (which the authors acknowledge) and the possible sources of environmental effects (read steroids) aside, I found the way the authors collected the facial metrics data ingenious. The authors measured the facial metrics from photos of students, varsity and professional hockey players. The students’ aggressiveness was assayed with a test (Point Subtraction Aggression Paradigm), while the hockey players were rated according to the number of penalty minutes per number of games played.
Since the differences in the facial metrics are not linked to differences in body size, the results of this study strengthen the view that along the course of human evolution, the facial metrics have faced (excuse the pun) selective pressures independent of body size.
Carre, J.M. and McCormick, 2008. In your face: facial metrics predict aggressive behaviour in the laboratory and in varsity and professional hockey players. Proc. Roy. Soc. B. 275: 2651-2656. doi:10.1098/rspb.2008.0873