The Price Equation and the Mathematics of Selection


Fifty years ago, a small one and a half page paper without a single reference was published in the leading journal Nature. The paper laid out the most general mathematical formulation of natural selection that would work for all kinds of selection processes and under any form of inheritance (not just biological evolution and Mendelian genes), although the paper discussed the issue in a genetical framework. Written by a maverick American expatriate in England, with no prior background of studying evolution or genetics, the paper had initially been turned down by the editor of Nature as too difficult to understand. Largely ignored by the evolutionary biology community till the 1990s, the Price Equation is now widely recognized as an extremely useful conceptualization, permitting the incorporation of non-genetic inheritance into evolutionary models, serving to clarify the relationship between kin-selection and group-selection, unifying varied approaches used in the past to model evolutionary change, and forming the foundation of multi-level selection theory.

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Correspondence to Amitabh Joshi.

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Amitabh Joshi studies and teaches evolutionary biology and population ecology at JNCASR, Bengaluru. He also has serious interests in poetry, history and philosophy, especially the history and philosophy of genetics and evolution.

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Joshi, A. The Price Equation and the Mathematics of Selection. Reson 25, 495–512 (2020).

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