Three converging lines of evidence show that variation in usage of signal forms reflects dialects. While chimpanzees are thought to have a biologically inherited set of gestural signals, our results suggest that the dialects observed are likely to be socially influenced.

Whether these signals are conventionalized (i.e., where arbitrary forms are socially learned and have a common shared meaning) within each community remains to be tested.

Finally, we uniquely documented cultural loss for over a generation, linked to demographic decline driven by human activity, emphasizing the significance of a stable social environment for cultural retention in chimpanzees. Our evidence highlights the urgent need to integrate chimpanzee cultural preservation with conservation strategies.