From individuals to populations: a tale of swarms, cannibals, ageing and human obesity

 9^th April
The Royal Society room, South Australian Musem

There can be few more important challenges in modern biology than explaining how the phenotypic features of organisms contribute to the populations, communities and ecosystems within which they exist, and how these in turn respond to changing environmental conditions. The phenotype sits at the confluence of influences arising from the genes and the environment and it is the phenotype which is subject to natural selection. Steve Simpson will use his team’s work on locusts and other insects to show how spanning individuals to ecosystems can be achieved by combining theory, laboratory and field experiments and by using techniques from a range of  disciplines, including molecular biology, neurophysiology, biochemistry, behaviour, mathematics, statistical physics, computer science, engineering, evolutionary theory and landscape ecology. Locust plagues are one of the most infamous insect scourges, affecting the lives of 1 in 10 people on the planet. But they have also provided important new clues into the causes of human obesity, how we age, and the complex behaviour of crowds. Steve takes us on a strange journey that begins in the midst of a locust swarm and ends with the human obesity epidemic. Along the way you will see what you can discover by ticking a locust’s leg with a paintbrush, how recreational drugs turn shy solitary locusts into swarming party animals, how robotic aircraft are being used to track swarms, how statistical physics offers the key to understanding collective movement, the sinister role played by cannibalism in marching bands of locusts and Mormon crickets, and how a powerful appetite for protein can explain not only locust mass marching but also human obesity and ageing.