Vocal Profiles of the Galagidae
Bushbabies or galagos make structurally distinct calls in three main contexts: 1) social cohesion; 2) anxiety and alarm; 3) agonistic contact. Up to 25 calls have been identified in the best-studied species, but many of these are rarely heard or relatively quiet, making them difficult to record. For this reason we make a distinction between the vocal repertoire (all the calls made by each species) and the vocal profile (a set of the most common structurally distinct call types). Species can be distinguished by a unique vocal profile, with at least one or two call types that are not given by other species. One call type, the vocal advertisement (VA), is given both by males and females to attract companions and to repel rivals. This call is particularly loud and useful in distinguishing species and is listed first in each profile.
The naming of calls is highly subjective. The call names used here are taken from the impressions of a number of authors. One problem is that calls may grade into one another through a series of intermediates, in much the same way as the colours of the rainbow, with a result that different authors may divide the continuum in different ways. However, the names provide useful labels for comparative studies.