Recent work in Evolutionary Phonology (Blevins 2005, 2006, Blevins & Wedel 2008, Yu 2007, among others) has developed alternate explanations for typological universals or tendencies found across the sound systems of unrelated languages. This research emphasizes the role of patterns of language use and language change in the development of cross-linguistic patterns, rather than placing the burden of explanation on synchronic cognitive factors (i.e., Universal Grammar).