Predation selection impacts social information use in guppies (Poecilia reticulata)

Social information use helps animals to rapidly acquire biologically relevant information, but it can increase competition or be erroneous. The "costly information' hypothesis proposes that animals especially rely on social information in high-risk contexts such as under predation pressure. However, whether predation drives the evolution of social learning remains enigmatic. Here we use artificial selection lines of Trinidadian guppies (Poecilia reticulata) that had been selected for predation survival for 3 generations (and control lines that were visually and olfactory exposed to predation but in a secured enclosure) to test how predation selects for social information use. In our study, social information use was assessed in a low-risk foraging context, which allows us to isolate evolved differences from acute responses under high-risk. Individuals observed a demonstrator on a screen solving a color association task, correctly or incorrectly, before attempting the task themselves. We show that individuals from both treatments learned the task, but only animals from the control lines relied on the use of social information during the process, while animals from the predation lines prioritized private information. Our results challenge the assumptions that social information use has adaptive benefits under increased predation risk. On the contrary, we propose that under high-predation certain social learning mechanisms may incur excessive costs due to, for instance, extensive acquisition time. We suggest that in a high-predation environment, disregarding social information and relying on personal information can be an adaptive strategy.