Corvids infer the mental states of conspecifics

Abstract

It is well known that humans represent the mental states of others and use these representations to successfully predict, understand, and manipulate their behaviour. This is an impressive ability. Many comparative psychologists believe that some non-human apes and monkeys attribute mental states to others. But is this ability unique to mammals? In this paper, I review findings from a range of behavioural studies on corvids, including food caching, food recaching and food sharing studies. In order to protect their caches from being pilfered, corvids successfully keep track of observing conspecifics, employ a number of caching and recaching strategies, and exploit environmental factors to reduce the amount of visual and auditory information available to observing conspecifics. When giving food items as gifts, corvids give items for which conspecifics have developed a preference. I argue that the available evidence supports the hypothesis that corvids attribute mental states to conspecifics. I further hypothesize that corvids do so through process-driven simulation and the running of non-verbal multimodal rules accomplished by a class of mental representations called semantic pointers.