Discussion
Our results show that individual generation time measured as the mean
age at reproduction summarizes the pace of an individual’s life-history
and has the potential to evolve in response to ecological pressures.
Male generation time was longer compared to females due to sex
differences in age-dependent reproduction and survival, likely caused by
differences in competitive regimes. We also found that in years where
competition was higher and average fitness was lower, recruit production
was lower and older individuals contributed relatively more to
population growth. In contrast, when populations were growing, younger
individuals contributed disproportionately more to population growth.
These results imply that fluctuations in competitive regimes associated
to population sizes, influence the mean age at reproduction, thereby
affecting the demographic characteristics of this metapopulation.