Is predator-prey coevolutlon an arms race?

Biologists have often used simple analogies to help them think about complex processes in evolution. The mutual evolution of predator and prey has often been conceived of as an arms race. An increase in the armaments of one contestant in the race simply causes the other contestant to increase armaments in response. This analogy implies that the evolution in the predator population of improved abilities to capture prey should result in an evolutionary response in the prey that improves its abilities to avoid capture. Conversely, the evolution of improved escape abilities should result in increased capture abilities. The general applicability of this arms race analogy has not been supported by mathematical models of predatorprey interactions.