Yahoo India Web Search

Sign In

Search results

  1. Dictionary
    natural selection
    /ˌnatʃ(ə)rəl sɪˈlɛkʃn/

    noun

    • 1. the process whereby organisms better adapted to their environment tend to survive and produce more offspring. The theory of its action was first fully expounded by Charles Darwin, and it is now regarded as be the main process that brings about evolution.

    Powered by Oxford Dictionaries

  2. www.britannica.com › science › evolution-scientificEvolution - Natural Selection, Adaptation, Genetics | Britannica

    3 days ago · Evolution - Natural Selection, Adaptation, Genetics: The central argument of Darwin’s theory of evolution starts with the existence of hereditary variation. Experience with animal and plant breeding had demonstrated to Darwin that variations can be developed that are “useful to man.” So, he reasoned, variations must occur in nature that are favourable or useful in some way to the organism itself in the struggle for existence. Favourable variations are ones that increase chances for ...

    • Genetic Drift

      The selection coefficient is a measure of the reduction in...

  3. Videos

    View all

  4. www.britannica.com › Types-of-selectionEvolution - Natural, Sexual, Artificial | Britannica

    5 days ago · Evolution - Natural, Sexual, Artificial: Natural selection can be studied by analyzing its effects on changing gene frequencies, but it can also be explored by examining its effects on the observable characteristics—or phenotypes—of individuals in a population. Distribution scales of phenotypic traits such as height, weight, number of progeny, or longevity typically show greater numbers of individuals with intermediate values and fewer and fewer toward the extremes—this is the so ...

    • Francisco Jose Ayala

  5. www.britannica.com › science › evolution-scientificEvolution - Genetic Drift, Natural Selection, Adaptation

    5 days ago · The selection coefficient is a measure of the reduction in fitness of a genotype. The selection coefficients in the example are s = 0 for A 2 A 2 and s = 0.5 for A 1 A 1 and for A 1 A 2. The different ways in which natural selection affects gene frequencies are illustrated by the following examples. Selection against one of the homozygotes

    • Francisco Jose Ayala

  6. People also ask

  7. en.wikipedia.org › wiki › SpeciationSpeciation - Wikipedia

    5 days ago · Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages. [1][2][3] Charles Darwin was the first to describe the role of natural selection in ...

  8. www.livescience.com › planet-earth › evolutionHow fast does evolution happen? - Live Science

    Sep 9, 2024 · First, let's define evolution, which is the process by which a species' genes or physical appearance changes gradually over time. The driving force is natural selection, in which individuals with ...

  9. darwinthenandnow.com › selection-the-principle-ofSelection, the Principle of Evolution • Darwin, Then and Now

    Sep 7, 2024 · For the museum’s Darwin exhibit, Eldridge uses the acronym to explain how the principles of variation, inheritance, selection, time, and adaptation drive natural selection. Selection is Charles Darwin’s foundational acting principle. In The Origin of Species, Darwin introduced the principle of selection as the pivotal action driving evolution.

  10. www.thoughtco.com › charles-darwins-finches-1224472Charles Darwin's Finches and the Theory of Evolution - ThoughtCo

    Sep 9, 2024 · Charles Darwin did not come up with the Theory of Evolution on this voyage. In fact, his grandfather Erasmus Darwin had already instilled the idea that species change through time. However, the Galapagos finches helped Darwin solidify his idea of natural selection. The favorable adaptations of Darwin's Finches' beaks were selected over ...