Human Communication Systems Evolve by Cultural Selection

Human communication systems, such as language, evolve culturally [Chater et al. 2009; Croft 2000]; their components undergo reproduction and variation. However, a role for selection in cultural evolutionary dynamics is less clear. Often neutral evolution (also known as 'drift') models, are used to explain the evolution of human communication systems [Blythe 2012; Nettle 1999; Reali and Griffiths 2010], and cultural evolution more generally [Bentley et al. 2004; Neiman 1995]. Under this account, cultural change is unbiased: for instance, vocabulary, baby names [Bentley, Hahn and Shennan 2004] and pottery designs [Neiman 1995] have been found to spread through random copying. This is a neutral account because all variants encountered are considered equal candidates for copying.