A model for the adaptive dynamics of the maturation age

A density-dependent time-continuous model with two groups of age is considered both from the ecological and from the evolutionary point of view. In the ecological context, the maturation age is dealt with as a parameter and the existence of a non-trivial equilibrium attracting every mon-zero solution is proved under some hypotheses including that the birth rate is an increasing function of the maturation age. In the evolutionary framework, conditions for the existence and uniqueness and for the property of being convergence-stable of the evolutionarily stable value of the maturation age are given. (C) 2000 Elsevier Science B.V. All rights reserved.