Scanning Electron Microscopic Analysis of Dental Wear on the Heavily Worn Second Molars of the Wild Japanese Monkey (Macaca fuscata)

Authors

Teruyuki Hojo, University of Occupational and Environmental Health, Japan

Abstract

Microscopic features on scanning electron micro-graphs of epoxy-replicas of the second molars of nine wild-caught adult female Japanese monkeys, Macaca fuscata, from Oita Takasakiyama, Kyushu, were measured using a digitizer. These monkeys had been fed a monkey-diet during three or four days of captivity before replicas were made. Six of these specimens showed such heavily worn second molars that narrow peripheral enamel bands surrounded large dentin exposures and the cusps of the others had been worn off. Microwear measurements from sites near facet 9 were compared with those of facet 9 of three kinds of hard-object feeding primates from the literature. The mean percentage of pits among all features (pits and scratches) in these samples was almost equal to those that have been reported previously for Pongo pygmaeus and Cebus apella, but tended to be smaller than those of Cercocebus albigena. The mean pit width of these specimens was larger than that of Pongo pygmaeus and was almost equal to those of Cercocebus albigena and Cebus apella. The mean scratch width of these samples was larger than those of Cebus apella and Pongo pygmaeus. These features and the significant differences between these samples and the nonhard-object eaters such as Colobus guereza place these Macaca samples in the category of hard-object feeders. Additional directly observed seasonal feeding behaviors that would confirm the dietary contribution to these features is now needed.

Recommended Citation

Hojo, Teruyuki (1991) "Scanning Electron Microscopic Analysis of Dental Wear on the Heavily Worn Second Molars of the Wild Japanese Monkey (Macaca fuscata)," Scanning Microscopy: Vol. 5: No. 2, Article 18.
Available at: https://digitalcommons.usu.edu/microscopy/vol5/iss2/18