Document Type


Date of Degree Completion

Spring 2022

Degree Name

Master of Science (MS)


Primate Behavior

Committee Chair

Mary Lee Jensvold

Second Committee Member

Jessica Mayhew

Third Committee Member

Susan Lonborg


Large-bodied apes have a large repertoire of intentional, flexible gestures. Gestures have a distinct form, production, usage, and comprehension. Large-bodied apes use multiple gestures in sequences while communicating with other individuals. This study analyzed gesture sequences in free-living eastern chimpanzees (Pan troglodytes schweinfurthii) in Gombe National Park, Tanzania, to explore the variation of gestures. I analyzed various gesture form components to investigate if chimpanzees change the form of repeated gestures used in sequences. I described each gesture by twelve morphological form cheremes and more descriptive components. The results suggest that chimpanzees change the form of repeated gestures in sequences. I observed a pattern that some form cheremes changed more often than others. The chimpanzees changed the form of their gesture for each repetition of the gesture in sequence. Additionally, the chimpanzees changed multiple form cheremes simultaneously. The findings align with previous studies indicating chimpanzees flexibly adjust their gestural communication.

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