Higher plant lateral organs are maintained at specific angles with respect to gravity, a quantity known as the ravitropic setpoint angle (GSA). Differences in the GSA of lateral branches are the major component of species-specific variation in plant form seen throughout nature. We have recently discovered the mechanistic basis of the ability of plants to maintain non-vertical branch angles and also shown that variation in auxin response in a single cell type is sufficient to alter lateral branch GSA. This project will extend our understanding by using computational modelling and experimentation to understand the control of plant architecture throughout nature.