This article is a case study of the scientific discussions on the birth of a zoological species that eventually came to be known as Arctocephalus philippii (Peters, 1866). It also examines the movement of the remains of a sea lion specimen from Chile to Germany and the discussions that arose in regard to its taxonomic definition. The paper argues that the material properties of this mobilized specimen, the circumstances of how it was hunted, transported and stored at the different museums, as well as the material aspects that later allowed it to be compared and analyzed, influenced the international debates on its classification between naturalists in England, Germany, Chile and Argentina. The first part reconstructs the context of sea lion's capture, transportation and transformation, while the second examines the discussion around this particular specimen a controversy hinged partly upon the issue of the conditions in which it was graphically reproduced and preserved at the museum.