Fig. 1.

The final structural equation model linking cotyledon damage (number of cotyledons removed) in Medicago lupulina to plant biomass, days to flowering, flower number and the fitness components of seed number and seed mass. Each arrow represents a causal relationship such that a change in the variable at the tail of the arrow is a direct cause of a change in the variable at the head. Non-significant paths are indicated by dotted arrows. The thickness of the solid arrows reflects the magnitude of the standardized SEM coefficients. Larger standardized coefficients (listed beside each significant path) indicate that the variable at the tail has a stronger effect on the variable at the head. The variance explained (R²) for each endogenous variable is listed beside that variable.