A definition of the theory of evolution by natural selection

Definitions of Evolutionary Terms Adaptation: The adjustment or changes in behavior, physiology, and structure of an organism to become more suited to an environment. According to Charles Darwin's theory of evolution by natural selection, organisms that possess heritable traits that enable them to better adapt to their environment compared with other members of their species will be more likely to survive, reproduce, and pass more of their genes on to the next generation. A double stranded DNA molecule that contains a series of specific genes along its length.

A definition of the theory of evolution by natural selection

Darwin's Theory of Natural Selection The pocess is by some limited to organic beings; by others it is applied to the inorganic and the psychical. It is also applied to explain the existence and growth of institutions, manners, language, civilization, and every product of human activity.
Evolution | Define Evolution at lausannecongress2018.com See Article History Selection, in biologythe preferential survival and reproduction or preferential elimination of individuals with certain genotypes genetic compositionsby means of natural or artificial controlling factors.
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EVOLUTION NEWS Charles Darwin - Scientific analysis of fossils shows that species have changed over long periods of time.
Natural selection - Wikipedia What is natural selection, and how is it central to the theory of evolution? Natural selection is how species evolve by adapting to their environment.

British Dictionary definitions for evolution evolution noun biology a gradual change in the characteristics of a population of animals or plants over successive generations: Used in various senses in medicine, mathematics, and general use, including "growth to maturity and development of an individual living thing" s.

Modern use in biology, of species, first attested by Scottish geologist Charles Lyell. Charles Darwin used the word only once, in the closing paragraph of "The Origin of Species"and preferred descent with modification, in part because evolution already had been used in the 18c.

But Victorian belief in progress prevailed along with brevityand Herbert Spencer and other biologists popularized evolution. A continuing process of change from one state or condition to another or from one form to another.

The theory that groups of organisms change with passage of time, mainly as a result of natural selection, so that descendants differ morphologically and physiologically from their ancestors. Published by Houghton Mifflin Company.

A definition of the theory of evolution by natural selection

The modern understanding of the origins of species is based on the theories of Charles Darwin combined with a modern knowledge of genetics based on the work of Gregor Mendel. Darwin observed there is a certain amount of variation of traits or characteristics among the different individuals belonging to a population.

Some of these traits confer fitness-they allow the individual organism that possesses them to survive in their environment better than other individuals who do not possess them and to leave more offspring.

The offspring then inherit the beneficial traits, and over time the adaptive trait spreads through the population. In twentieth century, the development of the the science of genetics helped explain the origin of the variation of the traits between individual organisms and the way in which they are passed from generation to generation.

This basic model of evolution has since been further refined, and the role of genetic drift and sexual selection in the evolution of populations has been recognized. See also natural selection sexual selection. See Notes at adaptation Darwin. A process of development and change from one state to another, as of the universe in its development through time.


Show More A Closer Look: Darwin's theory of evolution by natural selection assumed that tiny adaptations occur in organisms constantly over millions of years. Gradually, a new species develops that is distinct from its ancestors.

In the s, however, biologists Niles Eldredge and Stephen Jay Gould proposed that evolution by natural selection may not have been such a smooth and consistent process. Based on fossils from around the world that showed the abrupt appearance of new species, Eldredge and Gould suggested that evolution is better described through punctuated equilibrium.

That is, for long periods of time species remain virtually unchanged, not even gradually adapting. They are in equilibrium, in balance with the environment.

But when confronted with environmental challenges-sudden climate change, for example-organisms adapt quite quickly, perhaps in only a few thousand years.

These active periods are punctuations, after which a new equilibrium exists and species remain stable until the next punctuation.

Life on Earth is thought to have evolved in three stages. First came chemical evolutionin which organic molecules see also organic molecule were formed.In , Darwin published his famous On the Origin of Species by Means of Natural Selection, a tome of over pages that marshalled extensive evidence for his theory.

Publication of the book caused a furor - ev ery copy of the book was sold the day that it was released. Darwin's theory shows that evolution is the process of natural selection acting on random variation. Darwin's theory of evolution by natural selection assumed that tiny adaptations occur in organisms constantly over exceptionally long periods of time.

Gradually, a new species develops that is . Indeed evolution by natural selection is a promising case for a counterfactual study because it is a famous case of "simultaneous discovery. Natural selection is part of Darwin's theory of evolution saying that those individuals within a species that don't adapt well to their environment will eventually die off, while those that do adapt will continue on with future generations.

These are the basic tenets of evolution by natural selection as defined by Darwin. The following is a quote from Darwin.

A definition of the theory of evolution by natural selection

"Variation is a feature of natural populations and every population produces more progeny than its environment can manage.

Natural selection - definition of natural selection by The Free Dictionary