Potential of Japanese Macaques for Understanding Etiology and Seasonality of Repetitive Linear Enamel Hypoplasia in Nonhuman Primates.

Japanese macaques are ideal to advance understanding of a wide-spread pattern of recurrent developmental distress in great apes, preserved as repetitive linear enamel hypoplasia (rLEH). Not only are they numerous, unendangered, and well-studied, but they are distributed from warm-temperate evergreen habitats in southern Japan to cool-temperate habitats in the north, where they are adapted behaviorally and phenotypically to winter cold and seasonal undernutrition. We provide a pilot study to determine if enamel hypoplasia exists in Japanese macaques from the north and, if temporal patterns of enamel hypoplasia are consistent with seasonal cold, undernutrition and/or exposure to secondary plant compounds.