Catastrophism vs. Uniformitarianism

Jul 25, 2024

Catastrophism vs. Uniformitarianism

Overview

  • Catastrophism: Earth's features shaped by sudden, short-lived, violent events (e.g., great flood).
    • Concept popularized by James Ussher
    • Ussher calculated Earth was created on Oct 26, 4004 B.C. (6,000 years old)
  • Uniformitarianism: Earth's features shaped by continuous, long-term processes (e.g., erosion).
    • Concept developed by Charles Lyell
    • Proposed that geological processes at work today have always been at work
    • Influenced Charles Darwin's theory of evolution

Detailed Concepts

Catastrophism

  • Likened to a bar of soap: a sudden event can dramatically change its form
  • An example is the Great Flood, considered a cataclysmic event
  • Early teaching experiences recounted by the lecturer

Historical Theories

  • Isaac Newton and Georges-Louis Leclerc, Comte de Buffon
    • Newton's comet theory: a comet hitting the sun caused the separation of material that formed planets
    • Buffon's calculations: Earth older than previously thought (74,832 years by Buffon, modern science says 4.543 billion years)

Uniformitarianism

  • Charles Lyell:
    • Principles of Geology: processes like erosion have been shaping Earth uniformly over time
    • Influential work leading to the rejection of catastrophism in favor of gradualism
  • Lecturer's personal academic experience with the concept

Influence on Evolutionary Theory

  • Charles Darwin:
    • Studied under botanist John Stevens Henslow at Cambridge
    • Recommended for a global voyage (HMS Beagle)
    • Influenced by Lyell's books during the voyage
    • Observed that species evolve through natural selection over time
  • Alfred Russel Wallace:
    • Corresponded with Darwin
    • Cited economist Thomas Malthus’s principles on population dynamics
    • Independently conceived the idea of natural selection

Key Figures in Evolution

  • Jean-Baptiste Lamarck:
    • Proposed inheritance of acquired characteristics
    • Partly correct but largely flawed understanding of heredity
  • Thomas Malthus:
    • Wrote on the principle of population
    • Noted that population growth is limited by environmental constraints
    • Influenced the concept of