Wakibara / Poster

Wakibara, J ⁽¹⁾; Matsubara, M ⁽²⁾; and Hanya, G ⁽³⁾.

Affiliations: ^{(1, 3)} Laboratory of Human Evolution Studies, Kyoto University ⁽²⁾ Primate Research Institute, Kyoto University. ⁽¹⁾ To whom correspondence should be made.

     Frequency of geophagia amongst Japanese monkeys Macaca fuscata in natural and food enhanced situations: Implications on the role of geophagy. The frequency of soil eating by Japanese monkeys Macaca fuscata in a food enhanced and natural foraging situation respectively was compared over a one year period through observations of focal individuals. In both situations, geophagia was predominant in young animals, prevailed in afternoon hours and occurred at a more or less steady frequency on annual basis. The food-enhanced monkeys at Arashiyama consistently outweighed by far those relying on wild foods at Yakushima in soil eating rate even though the bulk of foods eaten at the former site is considered less toxic. The possibility that soils were eaten to detoxify foods at either of the sites is less implicated and the rather rich dietary profiles at both sites do not suggest that soil was eaten for nourishment. It is proposed that the eaten soils serve to alleviate gastric disorders related to intake of plant based foods. The overt difference in frequency of soil consumption between the two sites is discussed in relation to dietary differences. The need to gather soil-eating data from additional populations living in such contrasting feeding habitats is emphasized.