Evolution - Species, Genetics, Trees

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

Images & Videos

How Charles Darwin developed the theory of evolution

Brian Greene asks Richard Dawkins: Does God exist?

British naturalist Alfred Russel Wallace

Watch Earth's continents move, from 650 million years ago to 250 million years in the future

For Students

evolution summary

Read Next

Spiral Galaxy type Sa-Sb or Sa/Sb in the constellation Virgo. The majestic Sombrero Galaxy Messier 104 (M104) or NGC 4594. The team took six pictures of the galaxy, stitched them together to create the final composite image. Photo from May-June 2003

9 Britannica Articles That Explain the Meaning of Life

Charles Darwin, carbon print photograph by Julia Margaret Cameron, 1868.

What Darwin Got Right (and Wrong) About Evolution

10 Animals With Evolutionary Traits Plucked Straight Out of a Nightmare

9 Animals That Look Like Leaves

Skull of Homo heidelbergensis (fossils, hominids).

Human Ancestors

Discover

Pluto. The Changing Faces of Pluto. Most detailed view to date of the entire surface of the dwarf planet Pluto, as constructed from multiple NASA Hubble Space Telescope photographs taken from 2002 to 2003.

10 Important Dates in Pluto History

Periodical Cicada, Adult, Magicicada spp. Requires 17 years to complete development. Nymph splits its skin, and transforms into an adult. Feeds on sap of tree roots. Northern Illinois Brood. This brood is the largest emergence of cicadas anywhere

Why Do Some Cicadas Appear Only Every 17 Years?

9 of the World’s Deadliest Spiders

earthquake. Heavily damaged school in the town of Yingxiu after a major earthquake struck China's Sichuan Province on May 12, 2008.

The 6 Deadliest Earthquakes Since 1950

solar eclipse, sun, moon, astronomy, space

How Do You Tell the Difference Between Total, Annular, Solar, and Lunar Eclipses?

Still from the film Deliverance, 1919. The story of Helen Keller and Anne Sullivan. View shows Keller in the cockpit/front seat of an airplane.

How Did Helen Keller Fly a Plane?

Adolf Hitler (Nazi, nazism, German leader).

9 Things You Might Not Know About Adolf Hitler

Evolutionary trees are models that seek to reconstruct the evolutionary history of taxa—i.e., species or other groups of organisms, such as genera, families, or orders. The trees embrace two kinds of information related to evolutionary change, cladogenesis and anagenesis. The figure can be used to illustrate both kinds. The branching relationships of the trees reflect the relative relationships of ancestry, or cladogenesis. Thus, in the right side of the figure, humans and rhesus monkeys are seen to be more closely related to each other than either is to the horse. Stated another way, this tree shows that the last common ...(100 of 39215 words)

Access the full article

Help support true facts by becoming a member.