Mandrill visual gestures
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Mark E. Laidre
Abstract
Apes have rich gestural communication systems. But do monkeys? If so, what forms and functions do monkey gestures have, and how does the relationship between form and function originate developmentally? This chapter reports intensive observations aimed at answering these questions in the largest of all monkeys, the mandrill (Mandrillus sphinx). Nearly thirty captive mandrill groups distributed across three continents were studied over the course of a decade, some groups for three consecutive generations. Mandrills performed three visual gestures: slap ground, hand extension, and eye covering. While slap ground was distributed uniformly across individuals and groups, hand extension and eye covering – the two focal gestures of this chapter – showed restricted distributions that were consistent with their being learned rather than instinctive. Contrasting hand extension against eye covering for fifteen different signal parameters revealed that these two gestures had antithetical forms and functions but had similar developmental histories. Within each gesture the close correspondence between form and function suggested that ontogenetic ritualization contributed to both hand extension’s and eye covering’s origin. Furthermore, for eye covering the clustering of all known performers within a single group suggested this gesture was culturally transmitted. Broadly, these results suggest that multiple interacting factors, including instinct, learning, and culture may contribute to the emergence of monkey gestures. Follow-up experiments, however, remain critical for rigorously testing the developmental origins and potential cultural transmission of non-human gestures. Keywords: development; gestural acquisition; ontogenetic ritualization; cultural transmission; monkeys
Abstract
Apes have rich gestural communication systems. But do monkeys? If so, what forms and functions do monkey gestures have, and how does the relationship between form and function originate developmentally? This chapter reports intensive observations aimed at answering these questions in the largest of all monkeys, the mandrill (Mandrillus sphinx). Nearly thirty captive mandrill groups distributed across three continents were studied over the course of a decade, some groups for three consecutive generations. Mandrills performed three visual gestures: slap ground, hand extension, and eye covering. While slap ground was distributed uniformly across individuals and groups, hand extension and eye covering – the two focal gestures of this chapter – showed restricted distributions that were consistent with their being learned rather than instinctive. Contrasting hand extension against eye covering for fifteen different signal parameters revealed that these two gestures had antithetical forms and functions but had similar developmental histories. Within each gesture the close correspondence between form and function suggested that ontogenetic ritualization contributed to both hand extension’s and eye covering’s origin. Furthermore, for eye covering the clustering of all known performers within a single group suggested this gesture was culturally transmitted. Broadly, these results suggest that multiple interacting factors, including instinct, learning, and culture may contribute to the emergence of monkey gestures. Follow-up experiments, however, remain critical for rigorously testing the developmental origins and potential cultural transmission of non-human gestures. Keywords: development; gestural acquisition; ontogenetic ritualization; cultural transmission; monkeys
Chapters in this book
- Prelim pages i
- Table of contents v
- Acknowledgements ix
- About the contributors xi
- Introduction 1
-
Article
- Facial-vocal displays, gestures and language 13
-
Research Studies
- Does ontogenetic ritualization explain early communicative gestures in human infants? 33
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Non-human primates
- A mother gorilla’s variable use of touch to guide her infant 55
- Spontaneous use of gesture sequences in orangutans 73
- Handedness for manual gestures in great apes 93
- Mandrill visual gestures 113
- Gesture use in consortship 129
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New trends and debates
- A call for conformity 147
- Cognitivism, adaptationism and pointing 165
- Pointing 181
- Requesting behaviours within episodes of active sharing 199
-
Article
- Hands and faces 223
- Where next? 241
- Index 253
Chapters in this book
- Prelim pages i
- Table of contents v
- Acknowledgements ix
- About the contributors xi
- Introduction 1
-
Article
- Facial-vocal displays, gestures and language 13
-
Research Studies
- Does ontogenetic ritualization explain early communicative gestures in human infants? 33
-
Non-human primates
- A mother gorilla’s variable use of touch to guide her infant 55
- Spontaneous use of gesture sequences in orangutans 73
- Handedness for manual gestures in great apes 93
- Mandrill visual gestures 113
- Gesture use in consortship 129
-
New trends and debates
- A call for conformity 147
- Cognitivism, adaptationism and pointing 165
- Pointing 181
- Requesting behaviours within episodes of active sharing 199
-
Article
- Hands and faces 223
- Where next? 241
- Index 253
