New study examines animal behaviour

Professor Iain MacDonald of the Department of Actuarial Science was one of three contributors to a ground-breaking study on animal behaviour

Associate Professor Iain MacDonald of UCT's Department of Actuarial Science was one of the contributors to a new study on animal behaviour that meaningfully represents the motivational state of animals by observing their eating routine.

Completed over several years, it's a study that has taken the collaboration of three researchers on three continents.

Titled Modelling Time Series of Animal Behaviour by Means of a Latent-State Model with Feedback, the paper examines the eating behaviour of eight Scarce Bordered Straw (Helicoverpa armigera) caterpillars over a 19-hour period.

The purpose was to model the states underlying behaviour, such as hunger and satiety, in a way that can be dissociated from specific behaviours. For example, in the models animals can stop feeding even when hungry (as when we take a break during a meal) or can nibble when satiated.

MacDonald's tasks on the project included the mathematics, computing and writing. Professor Walter Zucchini of the University of Göttingen came up with the model structure and did most of the heavy computing. Professor David Raubenheimer of the University of Auckland contributed the animal behaviour expertise, and also provided the illustrative data for the study.

Both Raubenheimer and Zucchini have strong ties with UCT. Raubenheimer is a UCT graduate in biology and Zucchini was head of the Department of Statistical Sciences when he left for Germany in 1993.

The paper is published in the leading international journal, Biometrics.