Unifying heritability in evolutionary theory


Despite being widely used in both biology and psychology as if it were a single notion, heritability is not a unified concept. This is also true in evolutionary theory, in which the word ‘heritability’ has at least two technical definitions that only partly overlap. These yield two approaches to heritability: the ‘variance approach’ and the ‘regression approach.’ In this paper, I aim to unify these two approaches. After presenting them, I argue that a general notion of heritability ought to satisfy two desiderata—‘general applicability’ and ‘separability of the causes of resemblance.’ I argue that neither the variance nor the regression approach satisfies these two desiderata concomitantly. From there, I develop a general definition of heritability that relies on the distinction between intrinsic and extrinsic properties. I show that this general definition satisfies the two desiderata. I then illustrate the potential usefulness of this general definition in the context of microbiome research.

Studies in History and Philosophy of Science, 91, pp. 201–210.
Pierrick Bourrat
Pierrick Bourrat
Senior Lecturer & DECRA Fellow

My research interests include the various concepts deployed in evolutionary theory, causation, and the interplay between biological and cultural evolution.