 An important study is Robert Kohler’s Lords of the Fly (Kohler 1994), a history of Drosophila genetics originating from Thomas Hunt Morgan’s laboratory at Columbia University. Kohler attributes the success of this way of doing science to the enormous output of the Drosophila system in terms of newly described and mapped mutations. The fruit fly breeds relatively fast and is easy to keep in laboratories in large numbers, which increases the chance of detecting new mutations. Kohler refers to Drosophila as the “breeder-reactor” to capture this kind of fecundity, thus, his study is not unlike an ecology of the lab fruit fly. The elaborate techniques of genetic mapping developed in Morgan’s laboratory, which assigned each mutation a physical location on one of the fly’s four chromosomes, can also be viewed as a way of organizing laboratory work and keeping track of the zillions of mutants that were cropping up continuously. A genetic map is a systematic catalogue of mutants and thus a research tool as much as it is a theoretical model of the fly’s genetic system (cf. Weber 1998). Thus, most of what went on in Morgan’s laboratory is best described as breeding, maintaining, characterizing and cataloguing (by genetic mapping) fly strains. Very little of it had anything to do with testing genetic theories, even though the theoretical knowledge about regularities of gene transmission canonically known as “Mendel’s laws” was, of course, also considerably refined in the process (Darden 1991). However, classical genetic theory was also a means of discovering mutants and genes for further study, not an end in itself (Waters 2004). This is also evident in the way in which Drosophila was adapted to the age of the molecular biology (Weber 2005; Falk 2009).