1980    (R. S. Corruccini and J. S. Handler), Temporomandibular Joint Size Decrease in American Blacks: Evidence from Barbados. Jl. of Dental Research 59:1528

We assume that non-genetic, environmental factors have played the major role in TMJ size decrease; the most likely explanation is decreased chewing resistance (and growth stimulation) provided by the soft processed diets of modern urban individuals.