|Appears in Collections:||Psychology Journal Articles|
|Peer Review Status:||Refereed|
|Title:||Variation and context of yawns in captive chimpanzees (Pan troglodytes)|
|Citation:||Vick S & Paukner A (2010) Variation and context of yawns in captive chimpanzees (Pan troglodytes), American Journal of Primatology, 72 (3), pp. 262-269.|
|Abstract:||Primate yawns are usually categorised according to context (e.g. as a threat, anxious or rest yawn) but there has been little consideration of whether these yawns are best regarded as a unitary behaviour that only differs with respect to the context in which it is observed. This study examined the context and precise morphology of yawns in a group of 11 captive chimpanzees. Focal video sampling was used to describe the morphology and intensity of 124 yawns using ChimpFACS, a system for coding facial movements. Two distinct forms of yawn were identified, a full yawn and a yawn which is modified by additional actions which reduce the mouth aperture. These modified yawns may indicate some degree of voluntary control over facial movement in chimpanzees and consequently multiple functions of yawning according to context. To assess context effects, mean activity levels (resting, locomotion and grooming) and scratching rates were compared one minute before and after each yawn. Locomotion was significantly increased following both types of yawn, while scratching rates significantly increased following modified yawns but decreased following full yawns. In terms of individual differences, males did not yawn more than females although male yawns were of higher intensity, both in the degree of mouth opening and in the amount of associated head movement. These data indicate that yawning is associated with a change in activity levels in chimpanzees but only modified yawns may be related to increased arousal. Different types of yawn can therefore be differentiated at the morphological level as well as context level.|
|Rights:||The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author; you can only request a copy if you wish to use this work for your own research or private study.|
|Vick and Paukner chimpanzee yawning AJP STORRE.rtf||7.38 MB||RTF||Under Embargo until 31/12/2999 Request a copy|
|Vick and Paukner chimpanzee yawning AJP STORRE.pdf||491 kB||Adobe PDF||Under Embargo until 31/12/2999 Request a copy|
Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependant on the depositor still being contactable at their original email address.
This item is protected by original copyright
Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
If you believe that any material held in STORRE infringes copyright, please contact email@example.com providing details and we will remove the Work from public display in STORRE and investigate your claim.