Read Pesky Details: Essays for "Left Brain" Christians Page 2

  Chapter I - Variation under Domestication

  Causes of Variability

  Effects of Habit and of the Use or Disuse of Parts; Correlated Variation; Inheritance

  Character of Domestic Varieties; Difficulty of Distinguishing between Varieties and Species; Origin of Domestic Varieties from One or more Species

  Breeds of the Domestic Pigeon, their Differences and Origin

  Principles of Selection Anciently Followed, and their Effects

  Methodical and Unconscious Selection

  Circumstances Favorable to Man's Power of Selection

  Chapter II - Variation under Nature

  Individual Differences

  Doubtful Species

  Wide-ranging, Much Diffused, and Common Species Vary Most

  Species of the Larger Genera in Each Country Vary More Frequently than the Species of the Smaller Genera

  Many of the Species Included within the Larger Genera Resemble Varieties in Being Very Closely, but Unequally, Related to Each other, and in Having Restricted Ranges

  Summary

  Chapter III - Struggle for Existence

  The Term, Struggle for Existence, Used in a Large Sense

  Geometrical Ratio of Increase

  Nature of the Checks to Increase

  Complex Relations of All Animals and Plants to Each Other in the Struggle for Existence

  Struggle for Life Most Severe between Individuals and Varieties of the Same Species