The effects of age on olfactory learning and memory in the honey bee Apis mellifera

THE proboscis extension reflex (PER) has been used extensively in studies of bee learning. This paper reports the effect of age of bees on conditioning of the response. An initial experiment investigated acquisition and retention of PER conditioning in bees emerged from a sealed brood in a laboratory incubator. Reliable acquisition and retention of the learning was not achieved until bees were 6 days of age. With comparable learning and memory to mature forager bees only at day 10. In a second study, bees from the same colonies were reared in a full hive colony, and a much slower development of this behaviour was seen. The results suggest that the behavioural role of the bee in the hive colony is as important as brain maturation for olfactory learning. This was explored further by producing precocious learning abilities in young (3-day-old) bees by preventing their normal nurse bee activities. The results are discussed in terms of the anatomical maturation of the bee nervous system and behavioural demands on the olfactory system throughout adult development.