Are behavioural responses to eyespots in sticklebacks influenced by the visual environment? An experimental examination

Eyespots are taxonomically widespread colour patterns consisting of large concentric rings that are commonly assumed to protect prey by influencing the behaviours of predators. Although there is ample experimental evidence supporting an anti-predator function of eyespots in terrestrial animals, whether eyespots have a similar deterring function in aquatic animals remains unclear. Furthermore, studies in terrestrial systems suggest that the protective function of eyespots depends on ambient light conditions where predators encounter them, but this effect was never been tested in aquatic environments. Here, we examine how eyespots influence behavioural responses in an aquatic environment under different visual environments, using laboratory-reared three-spined sticklebacks (Gasterosteus aculeatus) as model predators. Specifically, we experimentally examined behavioural responses of sticklebacks towards artificial prey patterns (control vs eyespots) under two different light environment tr...