Variabilidade individual na dieta de Hylaeamys megacephalus (Rodentia, Cricetidae) em habitats florestais e de monocultura de palmeira de dendê na Amazônia Oriental

Abstract

In most studies on niche, occupation in individual variability to communities or populations is not taken into consideration. However, habitat differences and resource availability would also have influence on individual variations in medium and long term, causing significant effects on the diversification and speciation of animal species, since they affect the stability of the population. Individual specialization would then be a way to reduce the intraspecific competition in response to several factors, such as environmental variations, ecological pressures and resource polymorphisms. Individuals become more opportunistic when the intraspecific competition is high and preferred resources are scarce. This change should result in increased amplitude diet for individuals, since they add companies not previously used to his repertoire. As a result, the niche breadth of the population as a whole must increase are structurally less complex than natural forests, but their effects vary according to each ecological group, functional role and ecophysiological requirements. There are few studies on these environmental changes resulting from this monoculture on the tropical forest fauna. In the present study, we characterized the diet of rodent Hylaeamys megacephalus and evaluate the degree of individual variation in the function of the two diet inserted habitats in the Amazon biome. The diet of H. megacephalus specimens consists of 18 food items, 12 of which are animal-eight of plant origin, and only one unique item Forest. The items "palm fiber" (FOi% = 44%) and "whole seeds" (FOi% = 40%) have higher frequency of occurrence among individuals collected in palm plantation habitats, but "fruit squash palm "(IAi% = 85.4%) was the most important item in the diet. The observed data show that the environments, both plantation as forest affect the individual expertise of the population of Hylaeamys megacephalus.