Ecologists typically invoke "law-like" generalizations, ranging over "structural" and/or "functional" kinds, in order to explain generalizations about "historical" kinds (such as biological taxa)rather than vice versa. This practice is justified, since structural and functional kinds tend to correlate better with important ecological phenomena than do historical kinds. I support these contentions with three recent case studies. In one sense, therefore, ecology is, and should be, more nomothetic, or law-oriented, than idiographic, or historically oriented. This conclusion challenges several recent philosophical claims (...) about the nature of ecological science. (shrink)