Abstract
When considering the question of possible transformation and disappearance of scientific objects, it is useful to distinguish between epistemic and technical objects. This paper presents preliminary observations and offers a typology of obsolescence. It is based on several case studies drawn from the history of life sciences. The paper proceeds as follows: first, the dynamics of epistemic objects is considered through the examples of Carl Correns’ study of “xenia”, Alfred Kühn’s work on physiological developmental genetics, and Paul Zamecnik’s research on the protein biosynthesis. Second, the phasing out of technical objects is then separately discussed and illustrated by the example of radioactive tracing in biology – until recently, an established technique of visualization.