- Canopy photosynthesis models combined with optimization theory have been an important tool to understand environmental response and interspecific difference in canopy structure, but their predictions are often incorrect in a quantitative manner. Although evolutionary game theory and the dynamic modelling of leaf turnover have been suggested useful to solve this problem, there is no model that combined these together.

- Here we present a model of leaf area dynamics that incorporates game theory.

- Leaf area index (LAI; leaf area per unit ground area) is predicted to increase with an increasing degree of interaction between neighbour plants in light interception. LAI is also sensitive to the assumed vertical pattern of leaf shedding: LAI is greater if more leaves are assumed to be shed from higher positions in the canopy. Our model provides more realistic predictions of LAI than previous static optimization, dynamic optimization or static game theoretical models.

- We suggest that both leaf dynamics and game theoretical considerations of plant competition are indispensable to scale from individual leaf traits to the structure and functioning of vegetation stands.