The evolutionary history of wild and domestic brown rats ( Rattus norvegicus )

The brown rat ( Rattus norvegicus ) occupies nearly every terrestrial habitat with a human presence and is one of our most important model organisms. Despite this prevalence, gaps remain in understanding the evolution of brown rat commensalism, their global dispersal, and mechanisms underlying contemporary adaptations to diverse environments. In this Review, we explore recent advances in the evolutionary history of brown rats and discuss key challenges, including finding and accurately dating historical specimens, disentangling histories of multiple domestication events, and synthesizing functional variation in wild rat populations with the development of laboratory strains. Advances in zooarchaeology and population genomics will usher in a new golden age of research on the evolutionary biology of brown rats, with positive feedbacks on their use as biomedical models.