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Intentional communication has been studied extensively in primates, yet evidence from free- ranging non-ape species remains limited. Human-directed food-solicitation gestures have recently been described in Hanuman langurs (Semnopithecus entellus), but whether these behaviours show the behavioural markers associated with first-order intentionality remains unknown. In this work, we experimentally tested for these markers in free-ranging Hanuman langurs across six anthropogenic sites in southern West Bengal, India, conducting 30 experimental and 30 control trials at each site (360 in total) and quantifying behaviours commonly used to operationalize intentional communication. The experimental condition found audience checking, recipient-directed orientation, rapid approach responses, food-solicitation gestures and gestural flexibility, all of which were rare or absent under control conditions, with differences between the two significant at every site. Signalling also ceased once food was obtained, consistent with the stopping rule associated with an Apparently Satisfactory Outcome. Together, these findings demonstrate the presence of multiple behavioural hallmarks of first- order intentionality in the human-directed gestural communication of free-ranging Hanuman langurs. This extends the study of intentional communication beyond apes and offers new insight into the evolutionary distribution of intentionality-related traits across primates. |