Skip to main content Skip to Search Box
Definition: natural selection from The Penguin Dictionary of Science

A fundamental mechanism of Darwin's theory of evolution (➤Darwinism), still used by biologists to explain changes in allele frequencies in populations (➤evolution). It holds that individuals in a large population have different chances of survival determined by their genetic make-up: those with characteristics that weaken their capacity to survive (such as the inability to escape predators or obtain nutrients) will have less chance of reproducing and passing on their characteristics to succeeding generations. Evolution by natural selection can be observed directly and has been tested experimentally. It remains the central feature of modern evolutionary theory.

natural selection

From The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide
Process by which gene frequencies in a population change through certain individuals producing more descendants than others because they are better able to survive and reproduce in their environment. The accumulated effect of natural selection is to produce adaptations such as the insulating coat of a polar bear or the spadelike forelimbs of a mole. The process is slow, relying firstly on random variation in the genes of an organism being produced by mutation and secondly on the genetic recombination of sexual reproduction. It was recognized by English naturalists Charles Darwin and Alfred Russel Wallace as the main process driving evolution . Natural selection results in evolution in a way that was described by Charles Darwin: individual organisms within a particular species may show a wide range of variation because of differences in their genes ; predation, disease, and competition cause individuals to die; individuals with characteristics most suited to the environment are more…
6,439 results

Full text Article Natural Selection

From The Concise Corsini Encyclopedia of Psychology and Behavioral Science
Definitions of natural selection vary due to the long history of the discussion of this topic. According to Darwin’s theory of evolution, natural selection signifies the phenomenon that in the struggle for life only the favorable variants of a potentially much larger progeny survive. Advantageous…
| 1,191 words
Key concepts:

Full text Article natural selection

From Philip's Encyclopedia
In evolution , theory that advantageous change in an organism tends to be passed on to successive generations. Changes arise out of natural genetic variation , especially mutation . Those that give an individual organism a greater capacity for survival and reproduction in a particular environment…
| 112 words
Key concepts:

Full text Article NATURAL SELECTION

From Gaither's Dictionary of Scientific Quotations
English biologist and geneticist Natural Selection is stern, but she has her tolerant moods. In Seward, A.C. Darwin and Modern Science Heredity and Variation in Modern Lights (p. 100 ) University Press. Cambridge England . 1910. …
| 3,811 words
Key concepts:

Full text Article Natural selection

From The International Encyclopedia of Human Sexuality
adaptation evolution gene inheritance natural selection trait Natural selection is a causal process that leads to the emergence and evolution of biological traits. This process leads to some animals to survive and reproduce more effectively within their environment by enhancing or reducing certain…
| 739 words
Key concepts:

Full text Article natural selection

From Encyclopedia of Evolution
The top graphs indicate the frequency of people...
Natural selection is the process by which evolution produces adaptation . Other processes (such as genetic drift) cause evolution to occur, but in a random direction. Only natural selection guides the evolutionary process in a direction that produces adaptation to environmental and social…
| 5,047 words , 1 image
Key concepts:

Full text Article Natural Selection

From Brenner's Encyclopedia of Genetics
Dynamics of directional selection.
Natural selection occurs when differences among individuals cause differences in survival and reproduction. Evolution by natural selection occurs when these differences in survival and reproduction cause the population to evolve. In some populations of bacteria, a few cells carry plasmids that make…
| 4,365 words , 3 images
Key concepts:

Full text Article natural selection

From The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide
Process by which gene frequencies in a population change through certain individuals producing more descendants than others because they are better able to survive and reproduce in their environment. The accumulated effect of natural selection is to produce adaptations such as the insulating coat of…
| 266 words
Key concepts:

Full text Article Natural selection

From 50 Biology Ideas You Really Need to Know
Natural selection
The theory of evolution by natural selection explains how everything from birds to bacteria adapt to their environment, and ultimately helps explain biological diversity. Today, it is often associated with one man, Charles Darwin, but it could easily have been credited to Alfred Russel Wallace. …
| 1,432 words , 1 image
Key concepts:
Evolutionary approaches to the study of human behaviour are underpinned by the logic of adaptation (see s. 4 ) by natural selection. Natural selection was Charles Darwin’s great insight, although Alfred Russel Wallace came up with the same theory (see s. 8 ) almost simultaneously. It is a theory of…
| 304 words
Key concepts:

Full text Article NATURAL SELECTION, LAW OF

From Elsevier's Dictionary of Psychological Theories
This generalization, first proposed by the English naturalist Charles Darwin (1809-1882) and the British biologist Alfred Russel Wallace (1823-1913) in 1858, asserts that of the range of inheritable variations of traits in a population, those that contribute to an individual's survival will be the…
| 165 words
Key concepts:
Mind Map

Stack overflow
More Library Resources