What is the primary focus of the Red Queen hypothesis?

The primary focus of the Red Queen hypothesis is the co-evolution in parasite-host relationships. This hypothesis, proposed by evolutionary biologist Leigh Van Valen, suggests that species must continually adapt and evolve in response to the changing strategies of their rivals or enemies, such as parasites or predators, in order to maintain their relative fitness. The name comes from a statement in Lewis Carroll's "Through the Looking Glass," where the Red Queen tells Alice that it takes all the running you can do to stay in the same place.

In the context of parasite-host relationships, as hosts evolve defenses against parasites, the parasites simultaneously evolve counter-defenses. This ongoing evolutionary arms race emphasizes the dynamic character of species interactions, illustrating that evolution is not a linear process, but a constant struggle for survival, leading to both species’ continuous adaptations. This highlights the importance of understanding these interactions in the study of evolutionary biology, as they can drive significant changes in the genetic and phenotypic traits of both parasites and their hosts.