Published on

On the Origin of Species by Means of Natural Selection, Or, The Preservation of Favoured Races in the Struggle for Life


On the Origin of Species by Charles Darwin

This document provides a detailed summary of Charles Darwin's "On the Origin of Species," a pivotal work in the field of natural history that introduced the theory of evolution through natural selection.


  • Key Observations: Darwin's journey as a naturalist on the H.M.S. Beagle led to profound insights about the diversity of life.
  • Evolutionary Thought: He considered the possibility that species evolved from other species, challenging the notion of immutable species.

Variation Under Domestication

  • Variability in Domestic Species: Notable differences in domestic animals and plants, often exceeding wild species variations.
  • Role of Inheritance: Emphasizes the importance of hereditary traits in these variations.

Struggle for Existence and Natural Selection

  • Malthusian Influence: Applies Thomas Malthus's principles to the natural world, suggesting a constant struggle for existence.
  • Survival of the Fittest: Introduces the concept of natural selection, where advantageous traits lead to survival and reproduction.

Divergence of Character

  • Species Divergence: Discusses how species diverge from common ancestors, leading to specialization and new species formation.
  • Environmental Influence: Highlights the role of the environment and resource competition in this divergence.

Difficulties of the Theory

  • Challenges and Counterarguments: Addresses the gradual nature of evolutionary changes and the lack of intermediate forms in the fossil record.

Geological and Geographical Distribution

  • Supporting Evidence: Examines geographical distribution and geological succession of species as evidence for evolution.

Classification, Morphology, Embryology

  • Evolutionary Relationships: Links classification, morphology, and embryological development to evolutionary history.


  • Descent with Modification: Concludes that species descend from other species, with natural selection as a primary mechanism.

This summary encapsulates Darwin's revolutionary ideas, highlighting his methodical observations, the concept of natural selection, and the profound impact of his theory on our understanding of life's diversity.