What’s in a frame? Response to comments on “Bonobos and chimpanzees exhibit human-like framing effects”.

We recently reported a study where chimpanzees and bonobos faced decisions between a ‘framed’ option that provided either one or two pieces of fruit, and an alternative option that always provided a constant number of peanuts. We found that apes (especially males) chose the framed option more when it was presented as a gain—apes initially saw one piece of fruit, but sometimes got two after making a choice—than when it was framed as a loss—apes saw two fruits, but sometimes received only one. We argued that the apes showed human-like framing effects, because they judged the fruit option as more desirable when it was presented as a gain than as a loss, despite equivalent payoffs. In a commentary, Kanngiesser & Woike claimed that the apes actually exhibited a pattern opposite of that typically seen in humans. They further highlighted important differences between human and non- human animal decision-making tasks. We believe that the commentary missed a critical aspect of our methodology, as they interpreted our results in terms of risky choice framing—or the reflection effect—whereas our task was designed to probe attribute framing.