The Paradox of Stasis and the Nature of Explanations in Evolutionary Biology

Kaplan, Jonathan (2008) The Paradox of Stasis and the Nature of Explanations in Evolutionary Biology. In [2008] Philosophy of Science Assoc. 21st Biennial Mtg (Pittsburgh, PA): PSA 2008 Contributed Papers.

Abstract

Recently, a paper by Estes and Arnold claimed to have “solved” the paradox of evolutionary stasis; they claim that stabilizing selection, and only stabilizing selection, can explain the patterns of evolutionary divergence observed over “all timescales”. While Estes and Arnold clearly think of their work as identifying the processes that produce evolutionary stasis, close attention to their claims reveal that they do no such thing. Instead, Estes and Arnold identify a particular evolutionary pattern – stabilizing selection as a statistical descriptor – but fail to identify the processes that produce that pattern. This mistake is important; the slippage between pattern and process is common in population and quantitative genetics, and contributes to a persistent misunderstanding of the nature of explanations in evolutionary biology.