Science and representation: the case of genetic maps

At the beginning of the 20th century, the main objective of Mendelian hybridization was, through controlled crosses, to attain the expression of desired "factors", for example in crop improvement. Because of these aims, Mendel's principles were adopted faster among agronomists than academic sectors. The change from the Mendelian conception of factors to the first genetic maps consisted in looking at genes not as abstract and functional entities like in Mendelian studies, but to visualise them as dots on a line, as dots on a map in classical genetics. What genes could do wasn't any more the core interest; their localization on a map was privileged. This new conception was followed by a new way to study, interpret and represent the inheritance phenomena, also, a new way to conduct experiments different from Mendelian hybridization. The construction of the first genetic maps and their representations were a successful means to study, explain and represent different inheritance issues and was a new way in which genetic studies could be done. At the beginning, these maps were hypothetical representations that facilitated the handling of empirical data as well as the classification of mutants. Later on, the culture of mapping strongly contributed to the understanding of the mechanics of chromosomes and the hereditary transmission.