Lamarckism: The Theory of Acquired Characteristics

Jean-Baptiste Lamarck believed that an organism's environment creates a "need" for change. He thought animals could intentionally adapt during their lifetime.

Example: A blacksmith who develops large muscles through work would have babies born with naturally large muscles.

Key points of Lamarck's theory:

  • Internal Drive
  • Use and Disuse
  • Inherited Habits

Darwinism: Evolution by Natural Selection

Charles Darwin argued that evolution is a slow process that acts on populations, not individuals. It relies on genetic differences.

Example: In a drought, birds with slightly stronger beaks can crack hard seeds that others can't. They survive and pass those traits on.

Key points of Darwin's theory:

  • Genetic Variation
  • Overproduction
  • Selection Pressure

📊 Side-by-Side Comparison

Feature Lamarckism Darwinism
Who changes? The individual changes its own body. The population changes over generations.
Role of Environment Environment causes the change to happen. Environment selects existing variations.
Role of Effort Based on use, disuse, and 'need'. No effort involved; based on luck/genetics.
Scientific Proof Proven wrong (DNA doesn't work this way). Proven right (supported by modern genetics).

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