Although it is true that hands do sometimes suffer serious injury when humans fight, epidemiology of interpersonal violence does not support the suggestion by King (King, 2013) that the fist is a fragile and ineffective weapon. In modern societies, interpersonal violence is the most frequent cause of fracture of the facial skeleton (Lee, 2009), and the fist is the weapon that is most frequently used to fracture the bones of the face (Le et al., 2001). A Swedish study on interpersonal violence reported 63 facial fractures and 57 concussions inflicted by fists, but only eight fractures of the metacarpal or phalangeal bones (Boström, 1997). Thus, human fists are effective weapons and, when humans fight, faces break more frequently than fists.
We agree with King's comment that fists of modern humans are used primarily in the context of within-group fighting and to subdue rather than kill. When modern humans wish to commit homicide, weapons such as clubs, knives or guns are generally involved. Nevertheless, we can be confident that such lethal weapons were of less importance, and may not have existed, when human-like hand proportions evolved in basal hominins. Fighting with fists is likely to have been much more important in the lethal interpersonal violence and intergroup fighting of australopiths than is the case in Homo.
