A new study led by doctoral student Akiva Topper, Dr. Yotam Ben-Oren and Dr. Oren Kolodny at the Hebrew University challenges a basic assumption in evolutionary biology: that coevolution only happens when species live in the same place. Published in Proceedings of the National Academy of Sciences, the research argues that roaming predators can connect species separated by thousands of kilometers and create shared evolutionary pressures across continents.
The work focuses on mimicry, where different species evolve similar warning signals, such as colors, sounds or behaviors, to deter predators. Traditionally, mimicry has been viewed as a local process tied to shared predators in the same area. The authors instead propose that migrating predators can carry learned or inherited avoidance behavior between regions, effectively linking distant ecosystems. Their simulations modeled two separate populations of dangerous prey connected by mobile predators.
The results showed that predators moving between the two populations can drive the evolution of shared warning signals even when the prey species never meet. “The findings suggest that species do not necessarily need to overlap geographically to undergo coevolution,” the authors said. “Migratory agents moving between different areas may effectively connect distant ecosystems, allowing evolutionary interactions to occur over large geographic ranges.”
The simulations also point to Müllerian mimicry, in which multiple protected species benefit from sharing a warning signal, as a process that migrating predators may help spread across non-overlapping ranges. The researchers said local predator pressure and the timing of migrating predators entering the system relative to the start of warning-signal evolution could either promote or limit the process. They said the same principle may apply beyond mimicry, and cited possible real-world examples including venomous snakes and migratory birds of prey, monarch butterflies and Asclepias plants, and viruses spread by migrating hosts or vectors. The authors hope the study will inspire new empirical work looking for hidden evolutionary links across traditional geographic boundaries.
