Maasai identify male altruists by facial appearance

In this experimental study, we continue investigating an association between facial morphology and individual psychological characteristics. The study was conducted in the population of Maasai (Ngorongoro, Tanzania) in two stages during field trips in 2016 and 2021. At the first stage, we collected anthropological photo portraits from 305 individuals (123 women and 182 men) and interviewed them to identify the propensity to help others. Six generalized morphed portraits of Maasai (men and women) were created based on individual propensity to help. At the second stage of the study, portraits were presented to 200 Maasai, men and women from the same population. The portraits were evaluated according to the degree of expression of four qualities: physical strength, proneness to help others, a "good friend", and self-confidence. The results of the study revealed that representatives of the same population are able to distinguish altruistic men by their facial shape. Men who were prone to provide assistance to others were perceived as physically stronger. No such association was found for female portraits. The results are interpreted from the standpoint of evolutionary psychology.