1st Edition

Beyond Lamarckism Plasticity in Darwinian Evolution, 1890-1970

By Laurent Loison Copyright 2025
    344 Pages 27 B/W Illustrations
    by Routledge

    Over the past twenty years, the role of phenotypic plasticity in Darwinian evolution has become a hotly debated topic among biologists and philosophers of science. For instance, in the Extended Evolutionary Synthesis, a new form of evolutionary theory that aims to include processes not taken into account by standard theory (the Modern Synthesis), the question of the remarkable plasticity of living beings is central.

    Beyond Lamarckism, Plasticity in Darwinian Evolution shows that the evolutionary impact of plasticity was in fact debated long before the emergence of the current debate on the limits of the Modern Synthesis. The question of how the plasticity of organisms could play a causal role in Darwinian evolution was raised on two separate occasions. First, around 1900, with the emergence of the theory of “organic selection”. Second, during the formation of the Modern Synthesis itself, in the mid-20th century. Out of these reflections came a very large number of concepts, models, and many different terms (“organic selection”, “stabilizing selection”, “genetic assimilation”, “Baldwin effect”, etc.), which were often developed independently in various research traditions and empirical contexts. This book also looks at the reasons why these conceptions have been downplayed in the standard understanding of adaptive evolution.

    Showing the extraordinary complexity of this history, Beyond Lamarckism is aimed at readers interested in evolutionary theory, whether philosophers, biologists or historians.

    Introduction.

    Part I. The rise of organic selection: thinking plasticity ecologically

    1. Framing the issue from the viewpoint of natural selection. The confusing birth of organic selection in the pre-Mendelian era.

    2. The eclipse of organic selection. The case-study of French-speaking post-Lamarckian biology.

    3. The experimental turn, from plastic change to speciation.

    Conclusion of Part I

    Part II. Waddington and Schmalhausen: thinking plasticity developmentally

    Introduction of Part II

    4. ‘Autonomization’, ‘canalization’ and ‘genetic assimilation’. Towards a developmental perspective on the relationship between adaptability and adaptation. 

    5. A problematic issue: the creativity of the developmental process.

    6. An overlooked revolution? Creativity in the evolutionary building of a new reaction norm.

    Conclusion of Part II

    Part III. (dis?)Integration into the Modern Synthesis: thinking plasticiy genetically

    Introduction of Part III

    7. The Baldwin effect: “de-ecologizing” organic selection.

    8. Re-working Waddingtonian concepts within quantitative genetics.

    9. The complex fate of Waddingtonian concepts in the subsequent history of the Modern Synthesis.

    Conclusion of Part III

    General Conclusion.

    Biography

    Laurent Loison is a CNRS researcher in history and philosophy of biology (Paris, France). A major part of his work focuses on the history of the various forms of Lamarckism in biology over the last two centuries.