SCIENCE AT THE SHINE DOME canberra 2 - 4 may 2007

New Fellows Seminar

Wednesday, 2 May 2007

Professor Stephen Simpson
ARC Federation Fellow and Professor, School of Biological Sciences, University of Sydney

Steve Simpson obtained his BSc in entomology from the University of Queensland in Brisbane before undertaking his PhD on locust feeding behaviour at the University of London as a University of Queensland Travelling Scholar. He then moved to the Department of Experimental Psychology at the University of Oxford in the UK, where he worked on the neural bases of feeding in monkeys, before moving to the Zoology Department at Oxford as a Lecturer in entomology, animal behaviour and neurobiology. Steve was appointed University Lecturer in Zoology and Curator of Entomology in the University Museum of Natural History at the University of Oxford in 1986, then in 1998 to Professor of the Hope Entomological Collections. Steve has been a Visiting Professor at a number of universities overseas, and an Australian Research Council Federation Fellow in the School of Biological Sciences at the University of Sydney since 2005.

A tale of paintbrushes, cannibal crickets and human obesity

Locust plagues are one of the most infamous insect scourges, invading vast areas of Africa, Asia, Australia and the Americas. Locusts form plagues because they can change from shy, green, harmless grasshoppers into brightly coloured, swarming creatures when they experience crowding. In his talk Stephen shows that an important trigger for the change is bumping into other locusts. Stimulating touch-sensitive hairs on the back legs causes a rapid shift in behaviour, such that locusts become attracted to each other. Once an aggregation reaches a critical number of insects, the locusts suddenly start to move as one. This decision to start migrating emerges collectively as a result of local interactions between individuals. Stephen uses the example of the Mormon cricket of North America to show that these animals form vast marching bands because they are seeking protein. They keep marching because, if an insect stops, it is cannibalised by other crickets: they are on a forced march for protein. The search for protein is a powerful force in shaping the biology not only of crickets and locusts, but of all animals – including humans. Stephen shows that the appetite for protein plays a key role in human obesity.