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Accordingly, the metaphor Red Queen represents the situation in nature where creatures must adapt quickly to changing environmental threats just to survive from generation to generation. In Lewis Carroll's Through the Looking Glass, from which the metaphor is originally derived, Alice complains that she has to run just to stay in the same place. The character of the Red Queen appears as a representation of a chess piece. She has become a popular object of metaphor as a result of the dream-like scene in which she seizes Alice by the shoulder in order that they can run together very fast in a desperate attempt to keep up with the landscape. She then advises Alice that in order to get anywhere else, as opposed to merely remaining in the same place, one must run at least twice as fast.
The metaphor has been found appropriate for the descriptions of arms races. These comparisons may be made in the fields of military hardware, competition in commercial product markets and competition between people in society for wealth or esteem, but, most famously, the idea was introduced by Leigh van Valen to the discussion of arms races in the biological theory of evolution by natural selection.
The recognition of a simple example of a biological arms race (from Richard Dawkins) can be achieved by considering the contrast between two adaptations of the polar bear. This animal has a coat of hair which is thick to help the bear survive the cold of the arctic and white in order that the bear can stalk seals for food. For the first case the selection pressure is likely to be constant or subject to random change, in the second case the selection pressure is likely to increase steadily as selection for cautiousness in seals makes the average seal harder and harder for the bear to stalk successfully. As a result both the bear and the seal find themselves running a red queen's race over evolutionary time, each becoming better and better adapted (to stealth and caution respectively) but neither becoming any more successful (as they are engaged in a zero sum game).
Science writer Matt RidleyMatt (Matthew) Ridley (born February 7, 1958 at Newcastle upon Tyne) is a British science writer. He received a doctorate in zoology from the University of Oxford before commencing a career in science journalism. He worked as a science correspondent for T wrote a book The Red Queen in which he discussed the debate in theoretical biology over the adaptive benefit of sexual reproduction to those species in which it appears. The connection of the Red Queen to this debate arises from the fact that the traditionally accepted theory ( The Vicar of BrayThe character of The Vicar of Bray appears in a traditional English folk song with that title. The eponymous vicar was the clergyman of the parish of Bray on Thames, Berkshire. The lyrics recount his adaptability (some would say amorality) in embracing wh) only showed adaptive benefit at the level of the species or group, not at the level of the gene. By contrast, a Red-Queen-type theory that organisms are running cyclic arms races with their parasiteA parasite is an organism that lives in or on the living tissue of a host organism at the expense of it. The biological interaction between the host and the parasite is called parasitism. Parasitism is a type of symbiosis, by one definition, although anots can explain the utility of sexual reproduction at the level of the gene by positing that the role of sex is to preserve genes which are currently disadvantageous, but which will become advantageous against the background of a likely future population of parasites.
Sex is an evolutionary puzzle. In most sexual species, males make up half the population, yet they bear no offspring directly and generally contribute little to the survival of offspring. In addition, males and females must find each other to mate, and sexual selectionThe Descent of Man and Selection in Relation to Sex by Charles Darwin showing the tufted coquette Lophornis ornatus female on left, ornamented male on right. Sexual selection is the theory that competition for mates between individuals of the same sex dri often favors traits that reduce the survival of organisms. Thus, sex is highly inefficient.
One possible explanation for the fact that nearly all vertebratePetromyzontidae ( lampreys) Placodermi extinct Chondrichthyes (cartilaginous fish) Acanthodii extinct Actinopterygii (ray-finned fish) Actinistia ( coelacanths) Dipnoi ( lungfish) Amphibia ( amphibians) Reptilia ( reptiles) Aves ( birds) Mammalia ( mammals are sexual is that sex increases the rate at which adaptationAdaptation may refer to— Adaptation in biology, an anatomical structure, physiological process or behavioral trait that has evolved over a period of time by the process of natural selection that increases the likelihood of producing larger numbers of offs can occur. This is for two reasons. First, if an advantageous mutationThis article is about mutation in biology, for other meanings see: mutation (disambiguation). Mutations are permanent, transmissible changes to the genetic material (usually DNA or RNA) of a cell. Mutations can be caused by copying errors in the genetic m occurs in an asexual line, it is impossible for that mutation to spread without wiping out all other lines, which may have different advantageous mutations of their own. Second, it mixes up genes. Some genes might be advantageous only when paired with other genes, and sex increases the likelihood that such pairings will occur.
For sex to be advantageous for these reasons requires constant selection for changing conditions. One factor that might cause this is the constant arms race between parasites and their hosts. Parasites generally evolve quickly, due to their short lifespans. As they evolve, they attack their hosts in a variety of ways. Two consecutive generations might be faced with very different selective pressures. If this change is rapid enough, it might explain the persistence of sex.