- My research analyzes the use of evolutionary models for species delimitation. I show that recent accounts of scientific pluralism can make sense of debates in systematics by disambiguating empirical, methodological, and theoretical criticism of particular model-based and simulation studies. The analysis clarifies recent confusion about how practicing systematists approach the species problem(s). The account also provides rich territory for testing recent work on the appropriate role of values in science. My aims are (1) to help advance philosophy of systematics beyond the 70s-80s cladist wars, (2) to better focus scientific and philosophical criticism of particular evolutionary models, and (3) to apply philosophical, scientific, and public experiences to understand scientific objectivity and the moral responsibilities of scientists.