Geissmann, T., 1987: A sternal gland in the siamang gibbon (Hylobates syndactylus). International Journal of Primatology 8: 1-15.

A sternal gland in the siamang gibbon (Hylobates syndactylus)

T. Geissmann
Anthropological Institute, University Zürich-Irchel

Key words: Sternal gland; Hylobates syndactylus; siamang; olfactory communication; gibbons.

Abstract: The present report gives the first description of a sternal gland in the siamang gibbon, Hylobates syndactylus, and the first histological examination of a sternal gland in a hominoid primate other than the orang-utan. The sternal gland does not seem to be used for any kind of marking behavior, in contrast to the sternal glands in many other primates and some other mammals. The sternal gland of the siamang may be derived from a marking gland which specialized only secondarily to serve parallel functions like those served by the axillary organs of humans and the African apes. A role of the gland in olfactory communication and a possible minor role in thermoregulation are discussed.