Functional analysis and etiology

Cummins (1982) argues that etiological considerations are not onlyinsufficient butirrelevant for the determination offunction. I argue that his claim of irrelevance rests on a misrepresentation of the use of functions in evolutionary explanations. I go on to suggest how accepting anetiological constraint on functional analysis might help resolve some problems involving the use of functional explanations.Thanks to Bill Wimsatt, Greg Mikkelson, Dan McShea, Robert Cummins and the editor and referees of this journal for their comments on earlier drafts.