"There are many reasons to revisit the history of research on (TMV), beginning with the fact that it was the first virus to be identified and so marks the start of the field of . However, not every original example of a new biological category becomes a well-studied object in its own right ... As virology took off in the early twentieth century, TMV did become one of the best-studied viruses and remained at the forefront of the field. It was used to elucidate basic knowledge about the nature of viruses and served as a in as well as agriculture, where it had emerged. The fact that the first recognized virus came from plants—although es were rapidly identified—meant that virology was, from the outset, highly comparative ... Literature on the origins of often privileges and the contributions of the ... Yet early work with TMV inspired Max Delbrück and other early molecular biologists to take up the study of bacteriophages. Moreover, TMV itself became a prominent model system for understanding the molecular nature of heredity and the relationship between proteins and nucleic acids ... Notably, some of the main scientists involved in elucidating the double-helical structure of DNA were also studying TMV, which became a tool for cracking the ."