Abstract

Biological evolution allegedly requires a genealogical conception of species (i.e., that species are descent-based "historical entities" rather than similarity-based "natural kinds"). After considering David Hull's arguments for this view, this paper opts instead for individuating species primarily via genetic similarities, but in a way which avoids charges of "Essentialism". It is suggested that a genealogical conception of species actually derives from a biological version of Behaviorism plus an interrelated pair of confusions regarding evolution and identity. Current taxonomic method may favor the genealogical conception, but evolutionary theory-- as well as genetics and molecular biology--count against it.