What is an evolutionary arms race?

An evolutionary arms race refers to a cycle of coevolution between competing species, where adaptations in one species lead to counter-adaptations in another. This dynamic often occurs between predators and their prey, parasites and hosts, or two competing organisms in the same ecological niche.

In this context, as one species develops a new trait, such as a more effective means of catching prey or avoiding predation, the other species is driven to evolve its own adaptations in response. This results in a continual cycle of adaptation and counter-adaptation, which can escalate over time, much like an arms race in a military context where each side seeks to outdo the other with advancements.

Such evolutionary interactions can lead to significant changes in the traits of both species involved and can have profound impacts on their survival and reproductive success. This concept is central to understanding how species influence each other's evolution through their ecological relationships.