In this discussion note we argue against the findings presented in Hay & Bauer 2007, which show a positive correlation between population size and phoneme inventory size. We argue that the positive correlation is an artifact of the authors’ statistical technique and biased data set. Using a hierarchical mixed model to account for genealogical relatedness of languages, and a much larger and more diverse sample of the world’s languages, we find little support for population size as an explanatory predictor of phoneme inventory size once the genealogical relatedness of languages is accounted for.