ArgumentThis paper aims to understand the emergence of comparative anatomy in the eighteenth century in the Parisian Académie Royale des Sciences. As early as the 1670s, a program centered on animal anatomy was conceived, which was a first attempt to give some autonomy to studies on animals and to link anatomy with natural history, but it declined after 1690. However, a variety of studies on animals was published in theMémoiresof the Académie during the eighteenth century. We propose a descriptive typology (...) of them in order to explore the status of animals and the significance of anatomy in each type, and to determine, in particular, which elements of Perrault's program were passed on at the Académie throughout the century. We discuss the influence of this legacy on the development of comparative anatomy after 1750, especially in Daubenton's work. (shrink)

ArgumentHere I analyze the anatomical thought of the French physician and naturalist Félix Vicq d'Azyr (1748–1794) in order to bring to light its importance in the development of comparative anatomy at the end of the eighteenth century. I argue that his work and career can be understood as an ambitious program for a radical reform of all biomedical sciences and a reorganization of this whole field around comparative anatomy, on the conceptual as well as the institutional level. In particular, he (...) recommended a close connection between anatomical and physiological studies, and a generalization of the comparative approach towards organs and functions in man and animals. This conception led him not only to reform the scope, the methods, the style of description, and the vocabulary in anatomy, but also to construct a new classification of living beings and to pursue a quest for laws of organization. This strategy was successful, since Vicq d'Azyr was able to promote his thought as well as his institutional position efficiently. The Revolution and his untimely death prevented him from achieving his program, but his attempt would serve as an example for younger scientists like Cuvier. (shrink)

The history of biological systematics documents a continuing tension between classifications in terms of nested hierarchies congruent with branching diagrams (the ‘Tree of Life’) versus reticulated relations. The recognition of conflicting character distribution led to the dissolution of the scala naturae into reticulated systems, which were then transformed into phylogenetic trees by the addition of a vertical axis. The cladistic revolution in systematics resulted in a representation of phylogeny as a strictly bifurcating pattern (cladogram). Due to the ubiquity of character (...) conflict—at the genetic or morphological level, or at any level in between—some characters will necessarily have to be discarded ( qua noise) in favor of others in support of a strictly bifurcating phylogenetic tree. Pattern analysts will seek maximal congruence in the distribution of characters (ultimately of any kind) relative to a branching tree-topology; process explainers will call such tree-topologies into question by reference to incompatible evolutionary processes. Pattern analysts will argue that process explanations must not be brought to bear on pattern reconstruction; process explainers will insist that the reconstructed pattern requires a process explanation to become scientifically relevant, i.e., relevant to evolutionary theory. The core question driving the current debate about the adequacy of the ‘Tree of Life’ metaphor seems to be whether the systematic dichotomization of the living world is an adequate representation of the complex evolutionary history of global biodiversity. In ‘Questioning the Tree of Life’, it seems beneficial to draw at least four conceptual distinctions: pattern reconstruction versus process explanation as different epistemological approaches to the study of phylogeny; open versus closed systems as expressions of different kinds of population (species) structures; phylogenetic trees versus cladograms as representations of evolutionary processes versus patterns of relationships; and genes versus species as expressions of different levels of causal integration and evolutionary transformation. (shrink)

The philosophy of pattern cladism has been variously explained by reference to the work of Louis Agassiz. The present study analyzes Agassiz's attempt to combine an empirical approach to the study of nature with an idealistic philosophy. From this emerges the problem of empiricism and of the isomorphy between the order of nature and human thinking. The analysis of the writings of Louis Agassiz serves as the basis for discussion of the reality of natural groups as postulated by pattern cladists.

The relatively late acceptance of Darwinism in German biology and paleontology is frequently attributed to a lingering of Lamarckism, a persisting influence of German idealistic Naturphilosophie and Goethean romanticism. These factors are largely held responsible for the vitalism underlying theories of saltational and orthogenetic evolutionary change that characterize the writings of many German paleontologists during the first half of the 20th century. A prominent exponent of that tradition was Karl Beurlen, who is credited with having been the first German paleontologist (...) to present a full-fledged theory of saltational evolution and orthogenetic change. A review of Beurlen's writings reveals motives and concerns far more complex, however, and firmly rooted in contemporary völkisch thought and Aryan Science. Beurlen's mature theory of evolution can indeed be understood as his own contribution to Aryan Geology and Biology, tainted as it was with National-Socialist ideology. Evolutionary biologists of the time who opposed the theories of Beurlen and likeminded authors, i.e., idealistic morphology, typology, saltational change, orthogenesis and cyclism did so on Darwinian principles, which ultimately prevailed. But at the time when the battle was fought, their adherence to the principle of natural selection was likewise ideologically tainted, namely in terms of racial theory. National-Socialist ideology was unable to forge a unity of evolutionary theory in Germany even amongst those of its proponents who endorsed this ideology. (shrink)