Figure 3. Path analysis diagrams for intra-group relationships between growth and ageing variables measured on chicks, in response to the hormonal treatment of the reproductive mothers.

Control (a), E₂ (b) and CORT group (c). Arrow represent causal link between variables, and standardized estimates (which can be positive or negative) are indicated along their respective paths. The total effect is the sum of direct and indirect effects. Significant paths are indicated by solid arrows while the dashed arrow represents a non-significant path remaining in the selected model. R² is indicated in the box of each exogenous variable and represents the variation of the endogenous variable (i.e. body mass gain) explained by each corresponding exogenous variables. See text for statistical details. ROMs: reactive oxygen metabolites; OXY: plasma antioxidant capacities.