The rapid reception of Gregor Mendel's paper ‘Experiments on plant hybrids’ (1866) in the early decades of the twentieth century remains poorly understood. We will suggest that this reception should not exclusively be investigated as the spread of a theory, but also as the spread of an experimental and computational protocol. Early geneticists used Mendel's paper, as well as reviews of Mendelian experiments in a variety of other publications, to acquire a unique combination of experimental and mathematical skills. We will analyse annotations in copies of Mendel's paper itself, in early editions and translations of this paper, and in early textbooks, such as Reginald Punnett's Mendelism (1905) or Wilhelm Johannsen's Elemente der exakten Erblichkeitslehre (1909). We will examine how readers used copies of such works to reproduce the logic behind Mendelian experiments, either by recalculating results, or by retracing the underlying combinatorial reasoning. We will place particular emphasis on the emergent role of diagrams in teaching and learning the practice of Mendelian genetics.

Argument

During the early modern period, European naturalists were confronted with a rapidly growing body of new objects due to the recent geographic discoveries. According to Bruno Latour's model of “action at a distance” naturalists managed this situation by mobilizing and stabilizing specimens and inscriptions at the periphery of the known world, as well as accumulating, reshuffling, and processing that material in “centers of calculation.” This paper tries to resolve an ambiguity that lies in this model: While the work of naturalists was clearly dependent on local institutions, collections, and botanical gardens in particular, they nevertheless claimed universality for the interpretations of the natural world they propounded. Analysis will be based on a case study: In the 1730s Carl Linnaeus produced a series of manuscripts and printed books that allow us to reconstruct the sequence of translations which led from the first encounter with a “new” plant at the periphery of the known world (in the case of Linnaeus, Lapland, which he visited in 1732) to a major botanical center (the botanical garden of George Clifford, former director of the Dutch East India Company, who employed Linnaeus in 1736 and 1737 to catalog his collection). I will argue generally that the abstraction process that was constitutive of Linnaeus' universal plant taxonomy – the separation of “constant” species and genera from local “varieties”- did not take place exclusively in the centers of knowledge production. This abstraction process was rather coextensive with the global network of translation and exchange that connected such centers with each other and with their peripheries. The “map” of the plant world outlined by Linnaeus did not represent “things drawn together,” but rather “things being exchanged,” and the global circulation of specimens and inscriptions was the foundation on which its claim to universality rested.