The Costs of Reproduction in a Tropical Palm, Astrocaryum Mexicanum

(1) A combined demographic and energetic approach was used to try to elucidate the possible cost associated with reproduction in the tropical palm, Astrocaryum mexicanum. (2) Survival and reproduction were recorded for about one thousand palms over a 3-yr period. (3) Dry matter allocation calculations were carried out on the annual growth rates of 140 individuals for 3 yr and from harvesting fifty palms of a wide range of ages. (4) There was an increase in reproductive effort with age and an inverse correlation between various measures of reproductive cost and fecundity. (5) The 3-60% variation in reproductive effort for different ages, years and plots seems to be mainly controlled by the probability of reproduction rather than the amount of reproductive structures produced. (6) The physiological reproductive effort appears to be constant over a wide range of environments and ages.