Variability of learning in insects: From brain to behavior

Poster and program (PDF, 921 Kb)

Learning is a complex trait, and to study learning an interdisciplinary approach is needed. Learning is not restricted to higher animals, it also occurs in invertebrates such as nematodes, insects and snails. Studies on model organisms such as C. elegans, Drosophila, Aplysia and mouse have revealed that the genes and pathways involved in learning are remarkably conserved. Therefore, invertebrate model organisms are useful to study the mechanism of learning at the cellular level. For example, interdisciplinary research on two prominent insect model organisms, Drosophila - with its well known genetic possibilities- and the honeybee Apis mellifera - with its impressive learning capabilities and accessible brain- has provided a basic understanding of how learning is achieved at the cellular level.

What is often lacking in these studies is the notion of normal variation in learning ability and the evolutionary causes and consequences of this variation between individuals, populations and species. It can be assumed that learning is a costly trait and the ease and speed of memory formation can be expected to vary between species and between individuals within a species, depending on several factors e.g. the environmental variability that is encountered and the longevity of a species. Parasitoid wasps for instance are known to use associative learning to optimize their searching efficiency. Most species readily change their behavior after experience, but others do not, and these species are closely related. The recent recognition of genes that inhibit memory formation (memory suppressor genes) also indicates that sensitivity to stimuli that induce memory formation is subject to fine tuning mechanisms. The fact that profound differences in learning occur between closely related species, suggests that the differences in the level of neural plasticity are adaptations to the specific plasticity needs of a particular species.

In this symposium we want to emphasize differences in learning and focus on biological variation rather than try to minimize variation as is more common in physiological/neurobiological research. Insects will be our focal point since there are some extreme examples of variation in learning in these organisms, but contributions on non-insect species are not excluded. We welcome contributions dealing with evolution of learning behavior but also on mechanisms of learning, because understanding the neural mechanisms of learning, its properties, dynamics and constraints, is of ultimate importance for understanding learning at the behavioural level.

Convenor :Hans M. Smid, Laboratory of Entomology, Wageningen University
Co-convenor: Louise E.M. Vet, Netherlands Institute of Ecology