Model selection results from cubic spline model fitted to female chamois body mass data.

Models are distinguished by the functional forms of α₀ and β₀. Specifically, we allowed α₀ and β₀ to be constant across years (α₀; β₀), vary linearly with year (α₀(y); β₀(y)), quadratically with year (α₀(y²); β₀(y²)) or linearly with population density (α₀(d); β₀(d)). Maximum log-likelihoods (LL) and ΔAICs are shown for each site. The most parsimonious models for each site are highlighted in bold (i.e. have a ΔAIC value that is ≤6 and lower than all simpler nested versions; see Richards [40]). n is sample size for each site.