Abstract

The central aim of the dissertation is to recommend an account of species pluralism that addresses a wide range of biological situations without resulting in theoretical tension between the pluralistic parts of the account. Species pluralism holds that more than one species concept is necessary in order to adequately address the wide variety of grouping phenomena identifiable as species. Proper assessment of an account of species pluralism requires assessing the number of biological situations the account covers as well as determining whether the account fits within a single theoretical framework. An account of species pluralism that includes a large number of species concepts appears to have the benefit of covering a large of number of biological situations. However, such an account also runs the risk of not fitting neatly within a single theoretical framework. An account that includes species concepts from different theoretical frameworks is said to give rise to disciplinary discord. ;This dissertation will defend the claim that species pluralism is necessary in order to do biology properly. In particular, an account of species pluralism offered by Kitcher will be defended. Kitcher suggests that species pluralism ought to include neo-Darwinian species concepts as well as non-Darwinian species concepts. Although Kitcher's account runs the risk of disciplinary discord, arguments will be presented which suggest that both types of species concepts can be integrated within a single theoretical framework. Some of the ways in which the species John Alan Holmes concepts might be integrated involve relaxing theoretical jargon, re-conceptualizing the types of entities picked out as species by the various species concepts so that they fit into a single hierarchy, and developing research projects, as well as institutional organizations, that are acceptable to both neo-Darwinians and non-Darwinians