However, some researchers have suggested that the invention of weapons such as spears and bows and arrows made intertribal warfare among early humans so lethal that group selection did take over.

• 然而，一些研究人员认为随着诸如矛，弓和箭这些武器的发明，使早起人类部落之间的战争甚为惨烈，因而群体选择发挥起了效应。