Non-native ungulates indirectly impact foliar arthropods but not soil function

One of the greatest challenges in contemporary ecology is to understand how the homogenization of biodiversity at all levels of organization and spatial scales will influence the assembly of communities and the functioning of ecosystems. Such homogenization can occur through the gain of non-native species and the loss of native species. Here, we show that by disrupting a keystone mutualistic interaction, non-native ungulates indirectly impact foliar arthropod abundance and richness, but not soil properties (soil respiration, temperature and humidity), in a temperate forest of Patagonia. The results of this study show that the gain of non-native ungulates and the loss of a key interaction can trigger unnoticed cascading effects. Our findings highlight the importance of assessing biodiversity not only as the sum of different components but also through the direct and indirect interactions among them.