Our proposal will explore how viruses can manipulate animal behaviour, and how this in turn leads to increased viral success. We will do so by using as a model a three component ecological system composed of a specialist baculovirus (BV) that specifically infects the caterpillars of the moth Spodoptera exigua and the tomato plant where these later feed. Core to understanding how virus manipulate behaviour are three questions that will guide our proposal. Q1 - What is the cellular substrate manipulated by viruses? Q2 - What are the molecular mechanisms mediating those changes? Q3 - How do these changes interact with ecological factors to culminate in a behavioural manipulation that ensures maximal viral spread? Our model system has key features that will enable us to address these questions, including the ability to genetically manipulate all three ends; the virus (BV), the host (S. exigua) and the ecological setting (tomato plants). Addressing these questions requires a uniquely multidisciplinary approach such as the one proposed by our team formed by an insect virologist (CC), an insect neuroscientist (LPG), a plant geneticist and physiologist (JFG) and an ecologist (FY).