Dr Iliana Medina from the University of Melbourne and Dr William Allen from Swansea University led a global experiment investigating how different colours help animals avoid predators. The study, which was conducted across six continents, used over 15,000 artificial prey in three colour patterns: orange and black as a warning signal, dull brown for camouflage, and bright blue and black.
Their research, recently published in Science, found that the effectiveness of antipredator colour strategies depends on several factors including the type of predators present, the community of prey, and habitat conditions.
Dr Allen explained: “For a long time, scientists have wondered why some animals use one defence over the other – and the answer turns out to be complicated. The predator community, prey community and habitat are all influential. This helps explain why we see camouflaged and warning coloured animals all over the world.”
The study showed that predator communities have the greatest influence on which colour strategy is successful. In regions where predators compete more intensely for food, they are more likely to take risks by attacking prey that could be dangerous or unpleasant to eat. As a result, camouflage tends to work better in these high-predation areas.
However, camouflage does not always provide protection. In well-lit environments, camouflaged prey were easier for predators to spot compared to darker settings; these prey were attacked more often than those displaying classic warning colours. Additionally, if cryptic (camouflaged) prey are common in an area, predators become better at detecting them.
The findings suggest that multiple factors together determine whether camouflage or warning coloration offers greater protection for animals in any given situation.
Dr Medina said: “Some questions in ecology involve such a wide range of variables that only global collaboration and replication can bring us closer to understanding how nature works. It was a pleasure to work with such a diverse group of colleagues who made this research possible.”
The researchers believe their results will improve understanding about how antipredator colour strategies evolve and are distributed globally among animal species.