红皇后假说

诺贝尔经济奖得主达龙·阿杰姆奥卢与詹姆斯·A·罗宾逊在其著作《自由的窄廊》（The Narrow Corridor: States, Societies, and the Fate of Liberty） 中用红皇后假说比喻国家与社会力量的相互制衡。

概论

此假说名字的来源于《爱丽丝镜中奇遇》（爱丽丝梦游仙境的续作）里红皇后对爱丽丝说的一句话：

Now, here, you see, it takes all the running you can do, to keep in the same place.你必须尽力地不停地跑，才能使你保持在原地。

红皇后假说着重于物种间的协同进化，却忽略了外部因素，在生物进化论上仍存有争议。

The Red Queen hypothesis is a hypothesis in evolutionary biology proposed in 1973, that species must constantly adapt, evolve, and proliferate in order to survive while pitted against ever-evolving opposing species. The hypothesis was intended to explain the constant (age-independent) extinction probability as observed in the paleontological record caused by co-evolution between competing species; however, it has also been suggested that the Red Queen hypothesis explains the advantage of sexual reproduction (as opposed to asexual reproduction) at the level of individuals, and the positive correlation between speciation and extinction rates in most higher taxa.

Origin

In 1973, Leigh Van Valen proposed the hypothesis as an "explanatory tangent" to explain the "law of extinction" known as "Van Valen's law", which states that the probability of extinction does not depend on the lifetime of the species or higher-rank taxon, instead being constant over millions of years for any given taxon. However, the probability of extinction is strongly related to adaptive zones, because different taxa have different probabilities of extinction. In other words, extinction of a species occurs randomly with respect to age, but nonrandomly with respect to ecology. Collectively, these two observations suggest that the effective environment of any homogeneous group of organisms deteriorates at a stochastically constant rate. Van Valen proposed that this is the result of an evolutionary zero-sum game driven by interspecific competition: the evolutionary progress (= increase in fitness) of one species deteriorates the fitness of coexisting species, but because coexisting species evolve as well, no one species gains a long-term increase in fitness, and the overall fitness of the system remains constant.

Van Valen named the hypothesis "Red Queen" because under his hypothesis, species have to "run" or evolve in order to stay in the same place, or else go extinct.

Examples

Positive correlation between speciation and extinction rates (Stanley's rule)

Palaeontological data suggest that high speciation rates correlate with high extinction rates in almost all major taxa. This correlation has been attributed to a number of ecological factors, but it may result also from a Red Queen situation, in which each speciation event in a clade deteriorates the fitness of coexisting species in the same clade (provided that there is phylogenetic niche conservatism).

Evolution of sex

Discussions of the evolution of sex were not part of Van Valen's Red Queen hypothesis, which addressed evolution at scales above the species level. The microevolutionary version of the Red Queen hypothesis was proposed by Bell, also citing Lewis Carroll.

The Red Queen hypothesis is used independently by multiple researchers to explain the evolution of sex, the maintenance of sex, and the role of sex in response to parasites. In all cases, sexual reproduction confers species variability and a faster generational response to selection by making offspring genetically unique.

Sexual species are able to improve their genotype in changing conditions. Consequently, co-evolutionary interactions, between host and parasite, for example, may select for sexual reproduction in hosts in order to reduce the risk of infection.

Competing evolutionary ideas

A competing evolutionary idea is the court jester hypothesis, which indicates that an arms race is not the driving force of evolution on a large scale, but rather it is abiotic factors.

The Black Queen hypothesis is a theory of reductive evolution that suggests natural selection can drive organisms to reduce their genome size. In other words, a gene that confers a vital biological function can become dispensable for an individual organism if its community members express that gene in a "leaky" fashion. Like the Red Queen hypothesis, the Black Queen hypothesis is a theory of co-evolution.

Publication

Van Valen originally submitted his article to the Journal of Theoretical Biology, where it was accepted for publication. However, because "the manner of processing depended on payment of page charges", Van Valen withdrew his manuscript and founded a new Journal called Evolutionary Theory, in which he published his manuscript as the first paper. Van Valen's acknowledgement to the National Science Foundation ran: "I thank the National Science Foundation for regularly rejecting my (honest) grant applications for work on real organisms, thus forcing me into theoretical work".