Evolutionary paths in the Δν − ΔΠ₁ plane of stellar models from the grid presented in Sect. 3. Thick solid lines indicate periods of the evolution where electron degeneracy is strong in the core – ψ(r = 0) > 25. Dashed lines correspond to ψ(r = 0) < 25. For clarity, the nondegenerate part of the evolution is shown only for models with solar metallicity and without core overshooting.