Ontogeny and Phylogeny

“Ontogeny recapitulates phylogeny” was Haeckel’s answer—the wrong one—to the most vexing question of nineteenth-century biology: what is the relationship between individual development (ontogeny) and the evolution of species and lineages (phylogeny)? In this, the first major book on the subject in fifty years, Stephen Jay Gould documents the history of the idea of recapitulation from its first appearance among the pre-Socratics to its fall in the early twentieth century. Mr. Gould explores recapitulation as an idea that intrigued politicians and theologians as well as scientists. He shows that Haeckel’s hypothesis—that human fetuses with gill slits are, literally, tiny fish, exact replicas of their water-breathing ancestors—had an influence that extended beyond biology into education, criminology, psychoanalysis (Freud and Jung were devout recapitulationists), and racism. The theory of recapitulation, Gould argues, finally collapsed not from the weight of contrary data, but because the rise of Mendelian genetics rendered it untenable. Turning to modern concepts, Gould demonstrates that, even though the whole subject of parallels between ontogeny and phylogeny fell into disrepute, it is still one of the great themes of evolutionary biology. Heterochrony—changes in developmental timing, producing parallels between ontogeny and phylogeny—is shown to be crucial to an understanding of gene regulation, the key to any rapprochement between molecular and evolutionary biology. Gould argues that the primary evolutionary value of heterochrony may lie in immediate ecological advantages for slow or rapid maturation, rather than in long-term changes of form, as all previous theories proclaimed. Neoteny—the opposite of recapitulation—is shown to be the most important determinant of human evolution. We have evolved by retaining the juvenile characters of our ancestors and have achieved both behavioral flexibility and our characteristic morphology thereby (large brains by prolonged retention of rapid fetal growth rates, for example). Gould concludes that “there may be nothing new under the sun, but permutation of the old within complex systems can do wonders. As biologists, we deal directly with the kind of material complexity that confers an unbounded potential upon simple, continuous changes in underlying processes. This is the chief joy of our science.”

Table of Contents:
* *1. Prospectus * Part I: Recapitulation *2. The Analogistic Tradition from Anaximander to Bonnet * The Seeds of Recapitulation in Greek Science? * Ontogeny and Phylogeny in the Conflict of "Evolution" and Epigenesis: The Idyll of Charles Bonnet * Appendix: The Revolution in "Evolution" *3. Transcendental Origins, 1793--1860 * Naturphilosophie: An Expression of Developmentalism * Two Leading Recapitulationists among the Naturphilosophen: Oken and Meckel * Oken's Classification of Animals Linear Additions of Organs * J. F. Meckel's Sober Statement of the Same Principles * Serres and the French Transcendentalists * Recapitulation and the Theory of Developmental Arrests * Von Baer's Critique of Recapitulation * The Direction of Development and Classification of Animals * Von Baer and Naturphilosophie: What Is the Universal Direction of Development? * Louis Agassiz and the Threefold Parallelism *4. Evolutionary Triumph, 1859--1900 * Evolutionary Theory and Zoological Practice * Darwin and the Evolution of Von Baer' Laws * Evolution and the Mechanics of Recapitulation * Ernst Haeckel: Phylogeny as the Mechanical Cause of Ontogeny * The Mechanism of Recapitulation * The American Neo-Lamarckians: The Law of Acceleration as Evolution's Motor * Progressive Evolution by Acceleration * The Extent of Parallelism * Why Does Recapitulation Dominate the History of Life? * Alpheus Hyatt and Universal Acceleration * Lamarckism and the Memory Analogy * Recapitulation and Darwinism * Appendix: The Evolutionary Translation of von Baer's Laws *5. Pervasive Influence * Criminal Anthropology * Racism * Child Development * Primary Education * Freudian Psychoanalysis * Epilogue *6. Decline, Fall, and Generalization * A Clever Argument * An Empirical Critique * Organs or Ancestors: The Transformation of Haeckel's Heterochrony * Interpolations into Juvenile Stages * Introduction of Juvenile Features into the Adults of Descendants * What Had Become of von Baer's Critique? * Benign Neglect: Recapitulation and the Rise of Experimental Embryology * The Prior Assumptions of Recapitulation * Wilhelm His and His Physiological Embryology: A Preliminary Skirmish * Roux's Entwicklungsmechanik and the Biogenetic Low * Recapitulation and Substantive Issues in Experimental Embryology: The New Preformationism * Mendel's Resurrection, Haeckel's Fall, and the Generalization of Recapitulation * Part II: Heterocrony and Paedomorphosis *7. Heterochrony and the Parallel of Ontogeny and Phylogeny * Acceleration and Retardation * Confusion in and after Haeckel's Wake * Guidelines for a Resolution * The Reduction of de Beer's Categories of Heterochrony to Acceleration and Retardation * A Historical Paradox: The Supposed Dominance of Recapitulation * Dissociability and Heterochrony * Correlation and Disociability * Dissociation of the Three Processes * A Metric for Dissociation * Temporal Shift as a Mechanism of Dissociation * A Clock Model of Heterochrony * Appendix: A Note on the Multivariate Representation of Dissociation *8. The Ecological and Evolutionary Significance of Heterochrony * The Argument from Frequency * The Importance of Recapitulation * The Importance of Heterochronic Change: Selected Cases * Frequency of Paedomorphosis in the Origin of Higher Taxa * A Critique of the Classical Significance of Heterochrony * The Classical Arguments * Retrospective and Immediate Significance * Heterochrony, Ecology, and Life-History Strategies * The Potential Ease and Rapidity of Heterochronic Change * The Control of Metamorphosis in Insects * Amphibian Paedomorphosis and the Thyroid Gland *9. Progenesis and Neoteny Insect Progenesis * Prothetely and Metathetely * Paedogenesis (Parthenogenetic Progenesis) in Gall Midges and Beetles * Progenesis in Wingless, Parthenogenetic Aphids * Additional Cases of Progenesis with a Similar Ecological Basis * Neotenic Solitary Locusts: Are They an Exception to the Rule? * Amphibian Neoteny * The Ecological Determinants of Progenesis * Unstable Environments * Colonization * Parasites * Male Dispersal * Progenesis as an Adaptive Response to Pressures for Small Size * The Role of Heterochrony in Macroevolution: Contrasting Flexibilities for Progenesis and Neoteny * Progenesis * Neoteny * The Social Correlates of Neoteny in Higher Vertebrates *10. Retardation and Neoteny in Human Evolution * The Seeds of Neoteny * The Fetalization Theory of Louis Bolk * Bolk's Data * Bolk's Interpretation * Bolk's Evolutionary Theory * A Tradition of Argument * Retardation in Human Evolution * Morphology in the Matrix of Retardation * Of Enumeration * Of Prototypes * Of Correlation * The Adaptive Significance of Retarded Development *11. Epilogue * Notes * Bibliography * Glossary * Index