Pimentel Lima Albertina, Magnusson William Ernest
Coordenação de Pesquisa em Ecologia, Instituto Nacional de Pesquisas da Amazônia, CP 478, 69011-970 Manaus AM, Brazil e-mail:
Oecologia. 1998 Aug;116(1-2):259-266. doi: 10.1007/s004420050587.
This study investigates hypotheses about partitioning of food resources among all species and several size classes in an assemblage of diurnal leaf-litter frogs in central Amazonia. All species in this assemblage change the type and size of prey as they grow. An ordination of diet composition was significantly associated with frog size and species-specific behaviour. However, a partial Mantel analysis indicated that species explained about 1.5 times more of the variation in diet overlap between individuals than frog size. Diet and foraging activity are correlated in juveniles, but not in adults, and this result holds whether species are considered as statistically independent observations or whether relationships are analysed using phylogenetically independent contrasts. This study showed that the partitioning of food resources between species changes with the population size structures. Thus, intraspecific and interspecific changes in diet, coupled with different patterns of juvenile recruitment, cause diet segregation among species due to temporal segregation of equivalent size classes.
本研究调查了关于亚马逊中部日间落叶蛙群落中所有物种以及几个大小类别的食物资源分配的假设。该群落中的所有物种在生长过程中都会改变猎物的类型和大小。饮食组成的排序与青蛙的大小和物种特异性行为显著相关。然而，部分Mantel分析表明，物种对个体间饮食重叠变异的解释比青蛙大小多约1.5倍。饮食与觅食活动在幼体中相关，但在成体中不相关，无论物种被视为统计上独立的观察对象，还是使用系统发育独立对比来分析关系，这一结果都成立。本研究表明，物种间食物资源的分配随种群大小结构而变化。因此，种内和种间饮食的变化，再加上不同的幼体补充模式，由于同等大小类别的时间隔离而导致物种间的饮食分离。
