Colorful parasites: an overlooked frontier in animal coloration research

The diverse coloration of animals has fascinated researchers over the past centuries. A growing body of evidence has documented the many functions of animal coloration, ranging from mate attraction to predator avoidance. Yet, the adaptive functions of parasite coloration have been largely neglected in this context, despite the fact that many parasites across diverse taxonomic groups exhibit colorful body patterns. In this opinion article, we discuss the potential adaptive functions of color in parasites. We first summarize some potential functions of parasite coloration based on an intensive review of the existing literature. We then propose several possible ecological, evolutionary, and biogeographical hypotheses regarding patterns in parasite coloration and outline future directions for this intriguing study frontier.