Refining the stress gradient hypothesis for mixed species groups of African mammals.

ABSTRACT: Species interactions such as facilitation and predation influence food webs, yet it is unclear how they are mediated by environmental gradients. Here we test the stress gradient hypothesis which predicts that positive species interactions increase with stress. Drawing upon spatially-explicit data of large mammals in an African savanna, we tested how predation risk and primary productivity mediate the occurrence of mixed species groups. Controlling for habitat structure, predation risk by lions and primary productivity affected the frequency of mixed species groups in species-specific ways, likely reflecting distinct stress perceptions. To test whether mixed species groups indicate positive interactions, we conducted network analyses for specific scenarios. Under predation risk, dyadic asso

SUBMITTER: Kiffner C 

PROVIDER: S-EPMC9587046 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature