Geissmann, T. and Hulftegger, A. M. (1994). Olfactory communication in gibbons? In: Roeder, J.J.; Thierry, B.; Anderson, J.R. and Herrenschmidt, N. (eds.), Current primatology, vol. 2: Social development, learning and behaviour (pp. 199-206). Strasbourg: Université Louis Pasteur.

Olfactory communication in gibbons?

T. Geissmann¹ and A.-M. Hulftegger^2
1Anthropological Institute, University Zürich-Irchel, Zürich, Switzerland
²Tierspital Zürich-Irchel, Zürich, Switzerland

Key words: Skin glands; sternal glands; gibbons; Hylobates; histology; olfactory communication; thermoregulation.

Abstract: This report presents a study of the skin glands of virtually all gibbon species and describes their macroscopic and histological characteristics. In the siamang (Hylobates syndactylus), the sternal glands are particularly prominent and produce a strong scent. Distinct sternal glands also occur in H. agilis, H. hoolock, H. lar, H. moloch, H. muelleri, and H. pileatus. In gibbons of the concolor group, sternal glands frequently appear to be less well developed. Specialised skin glands also occur in other regions of the body. These appear to be especially important in the gibbons of the concolor group, in which secretions may result in reversible changes in the fur colouration of adult females. The functions of the specialised skin glands in gibbons are poorly understood. Although they appear to play a role in olfactory communication, they are apparently not used for any kind of marking behaviour. Secretory activity is increased by stress and under elevated temperatures. This suggests functional analogies to the axillary glands which occur in humans and the African apes.