Evolutionary pressure

Evolutionary pressure

Any cause that reduces reproductive success in a proportion of a population potentially exerts Evolutionary pressure or selection pressure.Fact|date=August 2007 With sufficient pressure, inherited traits that mitigate its effects - even if they would be deleterious in other circumstances - can become widely spread through a population.

Examples

Drug resistance in bacteria is an example of the outcome of evolutionary pressure.

The Malaria parasite can exert a selective pressure on populations. This pressure has led to natural selection for erythrocytes carrying the sickle cell hemoglobin gene mutation (Hb S)—causing sickle cell anaemia—in areas where malaria is a major health concern, because the condition grants some resistance to this infectious disease. Therefore, the concept can be described as the application of Charles Darwin's principle of "survival of the fittest" (which actually should be understood as "extinction of the un-fittest") via some selection mechanism.

It is a quantitative description of the amount of change occurring in processes investigated by evolutionary biology, but the formal concept is often extended to other areas of research.

In population genetics, selection pressure is usually expressed as a selection coefficient.


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • Evolutionary history of plants — Plants have evolved through increasing levels of complexity, from the earliest algal mats, through bryophytes, lycopods, ferns and gymnosperms to the complex angiosperms of today. While the simple plants continue to thrive, especially in the… …   Wikipedia

  • Evolutionary art — exploits the process of evolution to create an artwork which continually changes according to an evolutionary algorithm. In common with natural selection and animal husbandry, the members of a population undergoing artificial evolution modify… …   Wikipedia

  • Evolutionary history of life — Although evidence of early life is scarce and often difficult to interpret, it appears that life appeared on Earth relatively soon (on the geologic time scale) after the planet had cooled enough for liquid water to be present. The dominant theory …   Wikipedia

  • Evolutionary medicine — Charles Darwin’s daughter Anne, “the joy of the household” died aged 10 due to tuberculosis …   Wikipedia

  • Evolutionary arms race — In evolutionary biology, an evolutionary arms race is an evolutionary struggle between competing sets of co evolving genes that develop adaptations and counter adaptations against each other, resembling an arms race. The co evolving gene sets may …   Wikipedia

  • History of evolutionary thought — This article is about the history of evolutionary thought in biology. For the history of evolutionary thought in the social sciences, see Sociocultural evolution. For the history of religious discussions, see History of the creation evolution… …   Wikipedia

  • Social effect of evolutionary theory — The social effects of evolutionary thought have been considerable. As the scientific explanation of life s diversity has developed, it has often displaced alternative, sometimes very widely held, explanations. Because the theory of evolution… …   Wikipedia

  • Java Evolutionary Computation Toolkit — ECJ is a freeware evolutionary computation research system written in Java. It is a framework that supports a variety of evolutionary computation techniques, such as genetic algorithms, genetic programming, evolution strategies, coevolution,… …   Wikipedia

  • biological development — Introduction       the progressive changes in size, shape, and function during the life of an organism by which its genetic potentials (genotype) are translated into functioning mature systems (phenotype). Most modern philosophical outlooks would …   Universalium

  • community ecology — Introduction       study of the organization and functioning of communities (community), which are assemblages of interacting populations of the species living within a particular area or habitat.       As populations of species interact with one …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”