Trophic niche overlap decreases in related mesocarnivore species

Abstract

In natural environments, competition between species is a crucial factor for the survival or demise of populations. Therefore, understanding the mechanisms that promote species coexistence is crucial in community and evolutionary ecology. The phylogenetic limiting to similarity hypothesis (PLSH) posits that closely related species should experience greater competition due to niche conservatism, leading to higher overlap in resource use. However, studies have shown mixed results regarding the influence of phylogenetic distance and other abiotic and biotic factors on interspecific competition. This study, which is based on an extensive bibliographic review of more than 200 sources over nearly five decades, explores the role of phylogenetic relatedness, body mass differences, and environmental factors such as primary productivity, in shaping trophic niche overlap among mesocarnivores across ten global biomes. Our results suggest that phylogenetic distance and body mass differences are the most significant predictors of trophic niche overlap, while environmental factors like primary productivity also play a crucial role. These findings highlight the complexity of species interactions, emphasizing that trophic niche overlap is influenced by a combination of factors. This study contributes to a deeper understanding of the dynamics governing species coexistence and the assembly of ecological communities.