Thus one objective of this review is to examine the evidence for olfactory and non-olfactory communication. I will begin by discussing experimental methods and review the
literature on recruitment to a specific spatial location. I will then examine several potential communication mechanisms, ranking them in their classically hypothesized order of evolutionary complexity: contact and visuallybased communication, followed by olfactory
communication, and finishing with a discussion of acoustic communication (von Frisch,
1967; Kerr, 1969; Wille, 1983)