Natural selection

hide

Natural selection is the process by which heritable traits that make it more likely for an organism to survive and successfully reproduce become more common in a population over successive generations. It is a key mechanism of evolution.

The natural genetic variation within a population of organisms means that some individuals will survive and reproduce more successfully than others in their current environment. For example, the peppered moth exists in both light and dark colors in the United Kingdom, but during the industrial revolution many of the trees on which the moths rested became blackened by soot, giving the dark-colored moths an advantage in hiding from predators. This gave dark-colored moths a better chance of surviving to produce dark-colored offspring, and in just a few generations the majority of the moths were dark. Factors which affect reproductive success are also important, an issue which Charles Darwin developed in his ideas on sexual selection.

Natural selection acts on the phenotype, or the observable characteristics of an organism, but the genetic (heritable) basis of any phenotype which gives a reproductive advantage will increase in frequency over the following generations (see allele frequency). Over time, this process can result in adaptations that specialize organisms for particular ecological niches and may eventually result in the emergence of new species. In other words, natural selection is an important process (though not the only process) by which evolution takes place within a population of organisms.

Natural selection is one of the cornerstones of modern biology. The term was introduced by Darwin in his groundbreaking 1859 book On the Origin of Species, in which natural selection was described by analogy to artificial selection, a process by which animals with traits considered desirable by human breeders are systematically favored for reproduction. The concept of natural selection was originally developed in the absence of a valid theory of heredity; at the time of Darwin's writing, nothing was known of modern genetics. The union of traditional Darwinian evolution with subsequent discoveries in classical and molecular genetics is termed the modern evolutionary synthesis. Natural selection remains the primary explanation for adaptive evolution.

For more information about Natural selection, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with natural selection

results timeline


Darwin's mockingbirds DNA research may help species recovery

Darwin's mockingbirds DNA research may help species recovery

Biology / Evolution

created Nov 18, 2009 | popularity 4 / 5 (1) | comments 0

(PhysOrg.com) -- New research could help protect the future of a rare bird in the Galapagos Islands that was an inspiration for Darwin’s theory of evolution by natural selection, scientists report in a paper ...


Can a plant be altruistic?

Biology / Plants & Animals

created Nov 11, 2009 | popularity 4.8 / 5 (4) | comments 0

The concept of altruism has long been debated in philosophical circles, and more recently, evolutionary biologists have joined the debate. From the perspective of natural selection, altruism may have evolved because any ...


Caught in the act: Butterfly mate preference shows how 1 species can become 2

Caught in the act: Scientists find butterflies splitting into two species

Biology / Plants & Animals

created Nov 05, 2009 | popularity 4.5 / 5 (8) | comments 5

(PhysOrg.com) -- Breaking up may actually not be hard to do, say scientists who've found a population of tropical butterflies that may be on its way to a split into two distinct species.


Culture, not just genes, can drive evolutionary outcomes

Genes drive behaviour, but culture can select genes: study

Biology / Evolution

created Oct 28, 2009 | popularity 4 / 5 (2) | comments 0

Culture, not just genes, can drive evolutionary outcomes, according to a study released Wednesday that compares individualist and group-oriented societies across the globe.


Are humans still evolving? Absolutely, says new analysis of long-term survey of human health

Biology / Evolution

created Oct 19, 2009 | popularity 4 / 5 (21) | comments 36

Although advances in medical care have improved standards of living over time, humans aren't entirely sheltered from the forces of natural selection, a new study shows.


Time in a bottle: Scientists watch evolution unfold

Time in a bottle: Scientists watch evolution unfold

Biology / Evolution

created Oct 18, 2009 | popularity 4.6 / 5 (42) | comments 13

A 21-year Michigan State University experiment that distills the essence of evolution in laboratory flasks not only demonstrates natural selection at work, but could lead to biotechnology and medical research ...


High mortality rates may explain small body size

Biology / Evolution

created Oct 05, 2009 | popularity not rated yet | comments 0

A new study suggests that high mortality rates in small-bodied people, commonly known as pygmies, may be part of the reason for their small stature. The study, by Jay Stock and Andrea Migliano, both of the University of Cambridge, ...


Why Female Water Buffalo Have Horns but Impala Do Not?

Biology / Evolution

created Sep 17, 2009 | popularity 3.7 / 5 (3) | comments 0

(PhysOrg.com) -- The reason some female hoofed animals have horns while others do not has long puzzled evolutionary biologists, even the great Charles Darwin. But now a survey of 117 bovid species led by Ted Stankowich, professor ...


Robots Reveal Insights into Evolution

Robots Reveal Insights into Evolution

Electronics / Robotics

created Sep 16, 2009 | popularity 4.4 / 5 (13) | comments 22

(PhysOrg.com) -- In an ironic twist to our understanding of life, robots may offer a greater degree of realism for studying some of the intricacies of natural selection and evolution than real organisms offer. ...


Study examines the evolutionary fate of 'useless' traits

Study examines the evolutionary fate of 'useless' traits

Biology / Evolution

created Sep 08, 2009 | popularity 4 / 5 (1) | comments 1

What happens when traits no longer give creatures a competitive edge?


Ego City: Cities organized like human brains

Ego City: Cities organized like human brains

Medicine & Health / Research

created Sep 03, 2009 | popularity 4.2 / 5 (11) | comments 0

(PhysOrg.com) -- Cities are organized like brains, and the evolution of cities mirrors the evolution of human and animal brains, according to a new study by researchers at Rensselaer Polytechnic Institute.


Anthropologist researches evolution of Darwin’s theory

Anthropologist researches evolution of Darwin’s theory

Biology / Evolution

created Sep 02, 2009 | popularity not rated yet | comments 0

(PhysOrg.com) -- New research by University of Notre Dame anthropologist Agustin Fuentes, published recently in the European journal Anthropology Today, states that although Darwin’s basic ideas still form t ...


Mice living in sandy hills quickly evolved lighter coloration

Mice living in sandy hills quickly evolved lighter coloration

Biology / Evolution

created Aug 27, 2009 | popularity 4.8 / 5 (5) | comments 9

In a vivid illustration of natural selection at work, scientists at Harvard University have found that deer mice living in Nebraska's Sand Hills quickly evolved lighter coloration after glaciers deposited ...


Researchers find first-ever 'wanderlust gene' in tiny bony fish

Researchers find first-ever 'wanderlust gene' in tiny bony fish

Biology / Plants & Animals

created Aug 05, 2009 | popularity 5 / 5 (4) | comments 0

(PhysOrg.com) -- A gene previously associated with physical traits is also dictating behaviour in a tiny fish widely regarded as a living model of Darwin's natural selection theory, according to a University ...


After dinosaurs, mammals rise but their genomes get smaller

Biology / Evolution

created Jul 27, 2009 | popularity 4.5 / 5 (2) | comments 1

(PhysOrg.com) -- Evidence buried in the chromosomes of animals and plants strongly suggests only one group -- mammals -- have seen their genomes shrink after the dinosaurs' extinction. What's more, that trend continues today, ...