The many lives of companion species: a zooarchaeological and isotopic research on Wari dog remains from Castillo de Huarmey, Peru

• Combining zooarchaeology and multi-isotopic analyses reveals diverse life histories of ancient dogs. • The companion species concept should be broadened to include animals living with and off humans. • Castillo de Huarmey’s dogs were involved in both mundane and ceremonial activities. • At the Castillo de Huarmey, Peruvian Hairless Dog puppies received distinct treatment compared to other dogs. The widespread belief that dogs are humans’ closest companions has led archaeologists to use their remains as indicators of human diet and mobility. However, these highly social animals also held diverse social and economic roles, and their remains offer valuable insights into the animal management systems in past complex societies. This study expands the undertheorized concept of companion species and applies it to the analysis of dogs’ roles at the ceremonial-administrative center and elite necropolis of the Wari Empire (ca. 600–1050 CE), Castillo de Huarmey. Combining standard zooarchaeological methods with multi-isotopic analyses (δ 13 C, δ 15 N, δ 18 O, and 87 Sr/ 86 Sr) reveals that the life trajectories of the tested Castillo de Huarmey dogs were anchored in the site’s immediate area but were not uniform. Their roles ranged from hunting or pastoral dogs to companions or ignored scavengers. Many were buried among humans, suggesting important ideological functions. The examined assemblage also includes three individuals tentatively identified as the Peruvian Hairless Dog, an indigenous Andean breed now recognized as part of Peru’s cultural heritage. This study argues that the osteobiographies and isobiographies of Wari dogs reveal not only their dependence on humans but also complex multi-species relationships and the Wari economic focus on local environmental resources.