Innovating to solve a novel puzzle: wild Asian elephants vary in their ability to problem solve

An animal's capacity for innovation or solving novel problems likely has important implications for how quickly they can adapt to environmental change. Asian elephants, Elephas maximus, living in zoos have previously demonstrated a capacity to innovate, but problem solving has never been studied experimentally in a wild elephant population. We installed puzzle boxes with multiple possible solutions inside a protected area in western Thailand to determine individual variation in innovation, as well as other behavioural traits associated with elephants' problem solving, including persistence, exploratory diversity and neophilia. We recorded 77 elephants approaching the puzzle box, with 44 interacting with the box in their first exposure. Individuals varied widely in their success opening the doors of the puzzle box. Such success was influenced by persistence and exploratory diversity in both the first interaction as well as across multiple interactions. However, when considering each individual's overall innovation scores, which represented how many different doors elephants were able to open across all of their interactions with the puzzle box, only greater persistence and interaction number were associated with reaching a higher innovation score. We observed that elephants who interacted with the box multiple times learned to open a door of any type more quickly as their interactions increased, but we did not see evidence of learning to open specific door types over time. Overall, this study about how innovation and its associated behaviours vary in wild elephants not only informs our understanding of how a capacity for problem solving is expressed, but also how well elephants may be able to adapt to, overcome or avoid increasingly frequent interactions with humans within their natural habitat.