Nonlinear Costs

The nonlinear cost function is conceptual and not a measured biochemical law. Saturating benefits and compounding costs can produce an intermediate optimum rather than favoring indefinite senescence. The nonlinear cost formulation can represent a resource cost of producing asymmetric offspring. For nonlinear cost parameter values above one, the faster daughter's benefit saturates while the slower daughter's cost accelerates. When the faster daughter gains less than the slower daughter loses, larger asymmetry lowers combined average growth.