Olfactory sensitivity and discrimination of mixtures in the honeybeeApis mellifera

Summary The work reported here is motivated by questions relating to the perception of olfactory cues in the discrimination of nestmates and kin in the honeybeeApis mellifera. Two sets of experiments are discussed. The first deals with the perception of individual compounds in mixtures made up from various pairs of volatile (citral, geraniol, linalool, and limonene) and nonvolatile (un- and dodecanoic acids) compounds. The second deals with the ability of worker honeybees to discriminate between mixtures made up from the same two compounds (un- and dodecanoic acids; tri- and pentacosane) combined in different proportions. All experiments employ differential conditioning of the proboscis extension reflex as an assay of the ability of workers to discriminate between two odors. Results show that workers can relate mixtures to their component parts, and that workers can discriminate between mixtures of two very similar compounds as long as the proportions are relatively dissimilar.