Which description best fits punctuated equilibrium?

• A. Gradualism
• B. Punctuated equilibrium
• C. Coevolution
• D. Abiotic factors

Answer: (B)

Evolution can unfold in long phases of little change with brief, rapid shifts that produce new species. This pattern is punctuated equilibrium. It matches the fossil record well, where new species appear abruptly with few intermediates, suggesting short bursts of change rather than a steady, gradual pace. This idea often involves the influence of environmental changes or population dynamics triggering rapid evolution during speciation. By comparison, gradualism describes slow, continuous change over time; coevolution is about two or more species evolving in response to each other; abiotic factors are nonliving parts of the environment. So the description that highlights rapid change occurring after long periods of stasis best fits punctuated equilibrium.