A new study has found why some animals use bright colours to warn off predators while others opt to camouflage themselves to avoid attack.
The findings, which are published in Science, reveal when it comes to deterring predators, context is crucial and several factors play a part in determining whether a camouflage or warning strategy works best.
Evolutionary biologists and ecologists conducted the global experiment across six continents using more than 15,000 artificial prey in three different colors - a classic warning pattern of orange and black, a dull brown that blends in, and an unusual bright blue and black.
The study was led by Dr Iliana Medina, from the University of Melbourne, and Dr William Allen, from Swansea University. Dr Ylenia Chiari from the School of Life Sciences at the University of Nottingham was part of the research team who collected the data at one of the key locations for this study.
Dr. Chiari emphasized the significance of the project from its earliest stages, highlighting the transformative impact that this worldwide collaboration could have on the field.
The results we have achieved are extremely exciting in advancing our understanding of how animal coloration may have evolved,"
Her contribution to the study further reinforces the University of Nottingham's reputation as a global leader in research on animal coloration.
Lead author Dr Allen said: "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 discovered the predator community had the biggest impact on which prey colour was most successful. The team's results support the idea that when predators compete intensely for food, they are more likely to risk attacking prey that might be dangerous or distasteful. Hence, camouflage worked best in areas with lots of predation.
But, being cryptic doesn't always work. In bright environments, camouflaged prey was more visible than in darker environments and was attacked more than prey with classic warning colours. Familiarity with prey using different colour strategies is also important - in places where cryptic prey is abundant, hiding becomes less effective, as predators are better at looking for camouflage prey.
Overall the results showed how multiple mechanisms determine which strategy is more advantageous in a particular circumstance.
Dr Medina added: "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 say their findings will help now build better understanding of the evolution and global distribution of the most common antipredator color strategies in animals.
