Does Competition Really Bring Out the Worst? Testosterone, Social Distance and Inter-Male Competition Shape Parochial Altruism in Human Males Diekhof, Esther Kristina ; Wittmer, Susanne ; Reimers, Luise Abstract Publication: PLoS ONE Pub Date: July 2014 DOI: 10.1371/journal.pone.0098977 Bibcode: 2014PLoSO...998977D