The 'after you' gesture in a bird.

Gestures are ubiquitous in human communication, involving movements of body parts produced for a variety of purposes, such as pointing out objects (deictic gestures) or conveying messages (symbolic gestures)1 . While displays of body parts have been described in many animals2 , their functional similarity to human gestures has primarily been explored in great apes3 , 4 , with little research attention given to other animal groups. To date, only a few studies have provided evidence for deictic gestures in birds and fish5 , 6 , 7 , but it is unclear whether non-primate animals can employ symbolic gestures, such as waving to mean 'goodbye', which are, in humans, more cognitively demanding than deictic gestures1 . Here, we report that the Japanese tit (Parus minor), a socially monogamous bird, uses wing-fluttering to prompt their mated partner to enter the nest first, and that wing-fluttering functions as a symbolic gesture conveying a specific message ('after you'). Our findings encourage further research on animal gestures, which may help in understanding the evolution of complex communication, including language.