C. Everett’s ejectives/altitude correlation is not significant

I’ve now had a chance to take a closer look at Caleb Everett’s recent PLoS ONE article on the correlation between ejective consonants and altitude, and I think the ejective
distribution is explainable on purely classical grounds, that is,
common inheritance and areal diffusion. That is, it is NOT necessary to resort to
an explanation in terms of altitude. The classical explanation is preferable
since the mechanisms of inheritance and diffusion are observable in
plenty, whereas noone has yet observed the hypothesized mechanism whereby
the speakers start using more ejectives in response to moving to higher
altitudes. Continue reading