Comparative Study of Olfactory Learning and Memory in Apis cerana and Apis mellifera Foragers

Abstract

The honeybee is an important invertebrate model organism for reward on learning and memory research. Its value as a model organism in this area is rooted in its impressive capacity for learning and memory formation. Many lines of research have been reported on learning and memory in the last few decades. However, most research on learning and memory in honeybees has been performed in the Western honeybee, Apis mellifera. Therefore, the cognitive capabilities in the Eastern honeybee, Apis cerana remain obscure, despite their biological and economical importance. In order to understand the differences of learning and memory performance in the two species of honeybees, we investigated classical olfactory conditioning according to an appetitive Pavlovian conditioning paradigm based on the olfactory conditioning of the proboscis extension response (PER). Our present study demonstrated that learning and memory performance was different between two honeybee species. During the acquisition phase, there was no statistical difference between two species. In the retention phase, A. cerana was significantly better on olfactory learning and memory than that of A. mellifera after 1 hour. On the other hand, A. mellifera showed higher learning scores than A. cerana after 24 hours. These findings extend our understandings of mechanisms underlying learning and memory capabilities, which is an important basis for the further study of behavioral responses to various ecological and biological signals in two closely related honeybee species.