Last Will and Testament: Stephen Jay Gould's The Structure of Evolutionary Theory

I outline Gould's conception of evolutionary theory and his ways of contrasting it with contemporary Darwinism; a contemporary Darwinism that focuses on the natural selection of individual organisms. Gould argues for a hierarchical conception of the living world and of the evolutionary processes that have built that living world: organisms are built from smaller components (genes, cells) and are themselves components of groups, populations, species, lineages. Selection, drift and constraint are important to all of these levels of biological organization, not just that of individual organisms. Moreover, both drift and constraint are more important than orthodoxy supposes. While having some sympathy for both of these lines of argument, I argue that they are more problematic than Gould supposes, and that he understates the power and the heterogeneity of orthodox conceptions of life's evolution.