Over the years, research in natural history and comparative biology has used alternative ways of theorizing. This session considers several questions about these usages, for example:

• How does theorizing in natural history differ from theorizing in the mechanical-experimental tradition?
• How do the different theories of change (e.g. natural selection, inheritance of acquired characters, and internal drives) relate to one another?
• What is the relation between notions of teleology and theories of change?

Lamarck and Darwin, for example, were both natural historians who theorized, in different ways, about the dynamic properties of parts and wholes. Barker focuses on Lamarckism in order to describe the analytical requirements of an adequate teleological theory. Gerson describes the development of a new class of theories in natural history. Winther & Oyama explore three models of change that have been employed in various fields: selectional, instructional, and maturational.

Organized by: Rasmus Winther and Elihu Gerson

Gillian Barker, Bucknell University
"Feedback Structures, Causal Identity and Natural Teleology"

Lamarckian change and other natural-teleological notions such as biological function and organic agency are obviously closely related. If these notions are to be explanatory rather than being merely ways of describing phenomena that are correctly explained in non-teleological terms, then the systems that they describe must be characterized by causal or informational "feedback" structures, and these structures must themselves be genuinely explanatory rather than merely epiphenomenal. The explanatory status of feedback structures depends crucially on the distinction between subsisting entities that change over time and two kinds of pseudo-entities: aggregates of lower-level entities, and temporal series of related but distinct entities. What biological entities can we accept as being causally "real"? I explore several approaches to this question and their implications for the status of Lamarckian change and for natural teleology generally.

Elihu Gerson, Tremont Research Institute
"The Development of Mapping Theories in Natural History"

Natural history and the disciplines of comparative biology which descend from it are different in many ways from the disciplines which descend from natural philosophy. This paper considers the nature of one kind of specialized theorizing in natural history. From ancient times, the use of analogies as a means of describing and classifying played a critical part in philosophical thinking. This use of analogy became restricted and refined in certain ways during the eighteenth century. At the turn of the nineteenth century, an important invention appeared: naturalists began to construct systematic analogies among classification systems. These were called 'parallels' between the systems. The most important of these was the parallel between the taxonomic system (i.e., classification of organisms) and the morphological system (i.e., classification of body parts). In addition, there were parallels from the stratigraphic system of rocks to the organisms found fossilized in those rocks, between developmental stage and taxonomic system, and between developmental stage and morphological system. These parallels became of central importance to nineteenth century natural history. These parallels or mappings among classifications have all the properties of theories. They can be used to make predictions and they support counter-factuals. The traditional practice of natural history however, has been on the progressive restriction of descriptive possibilities and on robustness, rather than on prediction and verification.

Rasmus Winther, Indiana University, & Susan Oyama, City University of New York
"Selectional, Instructional and Maturational Theories in Evo-Devo and Behavior"

We examine three models of change that have been employed in various fields: selectional, instructional, and maturational. In evolutionary theory these have been associated, respectively, with natural selection, the inheritance of acquired characters, and different kinds of internal mechanisms. We explore the use of these models in several areas, including "evo-devo" (evolutionary developmental biology) and the psychology of learning and argue that the use of a common terminology has sometimes obscured the heterogeneity of processes involved. We also argue that the analysis of crucial but often implicit assumptions about hierarchical levels, internal and external forces, and part-whole relationships, for instance, can illuminate both the historical use of the three models and their possible usefulness to contemporary scholars.