evolution

Table of Contents

Introduction
General overview
- The evidence for evolution
  - The fossil record
  - Structural similarities
  - Embryonic development and vestiges
  - Biogeography
  - Molecular biology
- History of evolutionary theory
  - Early ideas
  - Charles Darwin
  - Modern conceptions
    - The Darwinian aftermath
    - The synthetic theory
    - Molecular biology and Earth sciences
- The cultural impact of evolutionary theory
  - Scientific acceptance and extension to other disciplines
  - Religious criticism and acceptance
  - Intelligent design and its critics
The science of evolution
- The process of evolution
  - Evolution as a genetic function
    - The concept of natural selection
    - Genetic variation in populations
      The gene pool
      Genetic variation and rate of evolution
      Measuring gene variability
    - The origin of genetic variation: mutations
      Gene mutations
      Chromosomal mutations
  - Dynamics of genetic change
    - Genetic equilibrium: the Hardy-Weinberg law
    - Processes of gene-frequency change
      Mutation
      Gene flow
      Genetic drift
  - The operation of natural selection in populations
    - Natural selection as a process of genetic change
      Selection against one of the homozygotes
      Overdominance
      Frequency-dependent selection
    - Types of selection
      Stabilizing selection
      Directional selection
      Diversifying selection
      Sexual selection
      Kin selection and reciprocal altruism
- Species and speciation
  - The concept of species
  - The origin of species
    - Reproductive isolation
      Ecological isolation
      Temporal isolation
      Ethological (behavioral) isolation
      Mechanical isolation
      Gametic isolation
      Hybrid inviability
      Hybrid sterility
      Hybrid breakdown
    - A model of speciation
    - Geographic speciation
    - Adaptive radiation
    - Quantum speciation
    - Polyploidy
  - Genetic differentiation during speciation
- Patterns and rates of species evolution
  - Evolution within a lineage and by lineage splitting
  - Convergent and parallel evolution
  - Gradual and punctuational evolution
  - Diversity and extinction
  - Evolution and development
- Reconstruction of evolutionary history
  - DNA and protein as informational macromolecules
  - Evolutionary trees
    - Distance methods
    - Maximum parsimony methods
    - Maximum likelihood methods
    - Evaluation of evolutionary trees
- Molecular evolution
  - Molecular phylogeny of genes
  - Multiplicity and rate heterogeneity
  - The molecular clock of evolution
  - The neutrality theory of molecular evolution

References & Edit History Quick Facts & Related Topics

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evolution: Facts & Related Content

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Facts

Also Known As	descent

Did You Know?

According to 2017 Gallup polls, more Americans believe in global warming than in evolution.
Human brain size expanded with evolution and ultimately tripled.
A panda's "thumb" is a wrist bone that elongated with evolution.
Scientists speculate that hiccuping is a vestigial reflex inherited from an aquatic ancestor.

Photos and Videos

major evolutionary events

evolution of the horse

homologies of vertebrate forelimbs

Darwin: On the Origin of Species

British naturalist Alfred Russel Wallace

German biologist August Weismann

Michelangelo: The Creation of Adam

Why don't humans have tails?

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Collage showing a dog plus a saber-toothed cat equaling a prehistoric, quadrupedal creature with thick limbs and dark, hairless skin.

The video thumbnail image shows a brown-speckled bird perched on a branch, singing with an open beak.

Brian Greene asks Richard Dawkins: Does God exist?

See All Videos and Images →

Topics

convergence catastrophe theory evolutionary tree molecular clock punctuated equilibrium model synthetic theory of evolution divergence human evolution Lamarckism last universal common ancestor metabolism death biological development growth reproduction environment cell philosophy of biology coloration sex

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Key People

Hugo de Vries

Dutch botanist and geneticist

Robert Broom

South African paleontologist

Charles Darwin

Charles Darwin

British naturalist

Huxley, Thomas Henry

Thomas Henry Huxley

British biologist

Charles Lyell

Charles Lyell

Scottish geologist

Herbert Spencer

Herbert Spencer

British philosopher

Henri Bergson

Henri Bergson

French philosopher

British naturalist Alfred Russel Wallace

Alfred Russel Wallace

British naturalist

Jean-Baptiste Lamarck

Jean-Baptiste Lamarck

French biologist

Alfred Sherwood Romer, 1965

Alfred Sherwood Romer

American biologist

Dana, James D.

James D. Dana

American geologist and mineralogist

Erasmus Darwin, detail of an oil painting by Joseph Wright, 1770; in the National Portrait Gallery, London

Erasmus Darwin

British physician

Pierre Teilhard de Chardin

French philosopher and paleontologist

Konrad Lorenz

Konrad Lorenz

Austrian zoologist

Theodosius Dobzhansky

American scientist

Richard Dawkins

Richard Dawkins

British biologist and writer

Weismann, August

August Weismann

German biologist

Karl Pearson

Karl Pearson

British mathematician

Ernst Haeckel

Ernst Haeckel

German embryologist

George Gaylord Simpson

American paleontologist

Quiz

greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)

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List

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