Three Quarter-Centuries of Cytology

Friedrich Miescher's Discovery in the Historiography of Genetics: From Contamination to Confusion, from Nuclein to DNA

In 1869, Johann Friedrich Miescher discovered a new substance in the nucleus of living cells. The substance, which he called nuclein, is now known as DNA, yet both Miescher's name and his theoretical ideas about nuclein are all but forgotten. This paper traces the trajectory of Miescher's reception in the historiography of genetics. To his critics, Miescher was a "contaminator," whose preparations were impure. Modern historians portrayed him as a "confuser," whose misunderstandings delayed the development of molecular biology. Each of these portrayals reflects the disciplinary context in which Miescher's work was evaluated. Using archival sources to unearth Miescher's unpublished speculations-including an analogy between the hereditary material and language, and a speculation that a series of asymmetric carbon atoms could account for hereditary variation-this paper clarifies the ways in which the past was judged through the lens of contemporary concerns. It also shows how organization, structure, function, and information were already being considered when nuclein was first discovered nearly 150 years ago.

Method as a function of "disciplinary landscape": C.D. Darlington and cytology, genetics and evolution, 1932-1950

This article considers the reception of British cytogeneticist C.D. Darlington's controversial 1932 book, Recent Advances in Cytology. Darlington's cytogenetic work, and the manner in which he made it relevant to evolutionary biology, marked an abrupt shift in the status and role of cytology in the life sciences. By focusing on Darlington's scientific method--a stark departure from anti-theoretical, empirical reasoning to a theoretical and speculative approach based on deduction from genetic first principles--the article characterises the relationships defining the "disciplinary landscape" of the life sciences of the time, namely those between cytology, genetics, and evolutionary theory.

Cyril Dean Darlington: the man who 'invented' the chromosome

Cyril Darlington (1903-1981) was the most famous cytologist in the world in the decades preceding the molecular revolution of the 1950s. He crossed disciplinary boundaries to create a synthesis of cytology, genetics and evolution by revealing the mechanics of chromosomal recombination and the importance of its evolution. Always controversial during his lifetime, obituaries ultimately referred to him as the 'Copernicus' or 'Newton' of cytology. This article reviews Darlington's scientific contributions, the reasons for their difficult reception at the time and their continuing relevance.