Kenneth Peter Aplin (1958-2019) was one of Australia's leading vertebrate systematists, well known as an anatomist, mammalogist, herpetologist, palaeontologist, and archaeologist. Of all the many groups of animals that he studied, he was most passionate about the genus Rattus, among the most diverse and successful of all modern mammalian genera. Ken developed an unusually acute 'eye' for distinguishing taxa in vertebrate groups often considered very challenging to systematists, like Rattus. This skill was borne in part of extensive fieldwork, especially in New Guinea, Australia, and across Asia. This let him encounter many different groups of animals firsthand and to develop a remarkable ability for understanding them on their own ground. Where most mammalogists would bring rat traps, Ken would bring a shovel, and he would get to work in the landscape around him, digging burrows out of the ground to uncover rats that the trapper rarely sees. Of course, his careful work as a systematist and anatomist also sprang from a career spent within the world of natural history museums and their collections, the primary resource that biodiversity scientists use to develop their skills and undertake their work. From his earliest days as a scientist, he also showed an abiding interest in archaeology, and the study of faunal remains in archaeological contexts was a major strand that wove across his career. In this volume, the Australian Museum celebrates the career of an extraordinary fieldworker and museum scientist who made enormous contributions to the study of Asia-Pacific biodiversity, present and past.