Red Queen Hypothesis - the hypothesis that adaptive evolution in one The species of a community causes a deterioration of the environment of other species. As a consequence, each species must evolve as fast as it can in order to continue to survive. It comes from Lewis Carroll's Through the Looking in which the Red Queen said to you see, it takes all Glass Alice, “Now, here, the running you can do, to keep in the same The Red Queen place.” Hypothesis is used to describe three ideas based on co-evolution relationships or evolutionary arms races; one relating to extinction probability, another to the value of sexual reproduction, the third to host-parasite/pathogen relationships. The original idea, proposed by Leigh Van Valen in 1973, with the paleontological perspective, is that co-evolution could lead to situations for which the probability of extinction is relatively constant over millions of years rather than being proportional to the population's lifetime. In tightly co-evolved interactions, e.g., predator and prey, or host and parasite, or herbivore and food plant, the sudden evolutionary change by one species could lead to the extinction of other species and that the probability of such changes might be reasonably independent of species age. This is the long term paleontological macroevolutionary perspective. The other idea, advocated by W.D. Hamilton, among others, with the neontological perspective, relates to the benefit of sexual reproduction. This idea is that co-evolution, particularly in evolutionary arms races between hosts and parasites, could lead to sustained oscillations in genotype frequencies. As one genotype of host is most susceptible, its most effective parasitic genotype will prosper. However, this forms a selection pressure to favor a resistant host. When that resistant host genotype appears or merely increases in numbers, a new selection pressure forms on the original parasite genotype, which is now less infectious or virulent in the new host genotype. Thus, one host genotype will replace a former one, only to be followed by parallel replacement of genotype in the parasite. Sexually reproducing species which allow recombination of alleles among different
The Red Queen Hypothesis - the hypothesis that adaptive evolution in one species of a community causes a deterioration of the environment of other species. As a consequence, each species must evolve as fast as it can in order to continue to survive. It comes from Lewis Carroll's Through the Looking Glass in which the Red Queen said to Alice, “Now, here, you see, it takes all the running you can do, to keep in the same place.” The Red Queen Hypothesis is used to describe three ideas based on co-evolution relationships or evolutionary arms races; one relating to extinction probability, another to the value of sexual reproduction, the third to host-parasite/pathogen relationships. The original idea, proposed by Leigh Van Valen in 1973, with the paleontological perspective, is that co-evolution could lead to situations for which the probability of extinction is relatively constant over millions of years rather than being proportional to the population's lifetime. In tightly co-evolved interactions, e.g., predator and prey, or host and parasite, or herbivore and food plant, the sudden evolutionary change by one species could lead to the extinction of other species and that the probability of such changes might be reasonably independent of species age. This is the long term paleontological macroevolutionary perspective. The other idea, advocated by W.D. Hamilton, among others, with the neontological perspective, relates to the benefit of sexual reproduction. This idea is that co-evolution, particularly in evolutionary arms races between hosts and parasites, could lead to sustained oscillations in genotype frequencies. As one genotype of host is most susceptible, its most effective parasitic genotype will prosper. However, this forms a selection pressure to favor a resistant host. When that resistant host genotype appears or merely increases in numbers, a new selection pressure forms on the original parasite genotype, which is now less infectious or virulent in the new host genotype. Thus, one host genotype will replace a former one, only to be followed by parallel replacement of genotype in the parasite. Sexually reproducing species which allow recombination of alleles among different
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