Morphology and diet are key factors in the ecology of organisms, determining aspects of the natural history and evolution of the species. In this work, we evaluated the diet-morphology relationship in an anuran population, measuring the influence of morphological traits on the variation in the diet of individuals of Leptodactylus luctator. For this purpose, we collected individuals from a natural grassland habitat in southern Brazil. We analysed the stomach content of individuals and classified the consumed food items up to the classification level of order. We also measured four morphological traits per individual of L. luctator: distance between eyes, relative limb length, relative mouth width (gape) and snout-vent length. We applied Linear Mixed Effect Models to evaluate the relationship of anuran morphological traits, number of prey taxa and volume of consumed prey. We tested the hypothesis that the configuration of predator morphological traits determines variations in prey consumption patterns. Our results indicate that the body size of L. luctator was not directly related to the diet composition but the individuals’ gape is directly and positively related to the number of consumed taxa. This suggests that gape limitation could be a limiting factor in prey selection. The capacity to consume a wide variety of prey taxa could be an advantage in unpredictable environments, especially those with great daily thermal amplitudes such as the subtropical Brazilian grasslands. Keywords: Leptodactylus luctator, diet, amphibian, ecomorphology, functional ecology
Read full abstract