Researchers using puzzle boxes, rain sticks and papier-mâché balls are studying captive gray wolves at the Oakland Zoo and the California Wolf Center to evaluate personality and problem-solving skills of the endangered animals.

The novel research out of University of California, Davis, which also incorporates hundreds of hours of video and observational surveys, is seeking to shed new light on the lives of gray wolves, how they interact as part of a pack and respond to strange, new things