Mirror self-recognition in gorillas (Gorilla gorilla gorilla): A review and evaluation of mark test replications and variants
Affiliation
University of Chester; Kyoto University Graduate School of Letters; University at Albany, State University of New YorkPublication Date
2022-01-07Metadata
Show full item recordAbstract
Mirror self-recognition (MSR), widely regarded as an indicator of self-awareness, has not been demonstrated consistently in gorillas. We aimed to examine this issue by setting out a method to evaluate gorilla self-recognition studies that is objective, quantifiable, and easy to replicate. Using Suarez and Gallup’s (1981) study as a reference point, we drew up a list of 15 methodological criteria and assigned scores to all published studies of gorilla MSR for both methodology and outcomes. Key features of studies finding both mark-directed and spontaneous self-directed responses included visually inaccessible marks, controls for tactile and olfactory cues, subjects who were at least five years old, and clearly distinguishing between responses in front of versus away from the mirror. Additional important criteria include videotaping the tests, having more than one subject, subjects with adequate social rearing, reporting post-marking observations with mirror absent, and giving mirror exposure in a social versus individual setting. Our prediction that MSR studies would obtain progressively higher scores as procedures and behavioural coding practices improved over time was supported for methods, but not for outcomes. These findings illustrate that methodological rigour does not guarantee stronger evidence of self-recognition in gorillas; methodological differences alone do not explain the inconsistent evidence for MSR in gorillas. By implication, it might be suggested that, in general, gorillas do not show compelling evidence of MSR. We advocate that future MSR studies incorporate the same criteria to optimize the quality of attempts to clarify the self-recognition abilities of gorillas as well as other species.Citation
Murray, L. E., Anderson, J. R. & Gallup, G. G., Jr. (2022). Mirror self-recognition in gorillas (Gorilla gorilla gorilla): A review of mark test replications and variants. Animal Cognition, 25, 783–792. https://doi.org/10.1007/s10071-021-01592-3Publisher
SpringerJournal
Animal CognitionAdditional Links
https://link.springer.com/article/10.1007/s10071-021-01592-3Type
ArticleISSN
1435-9448EISSN
1435-9456Collections
Except where otherwise noted, this item's license is described as https://creativecommons.org/licenses/by/4.0/
Related items
Showing items related by title, author, creator and subject.
-
Video-mediated behavior in gorillas (G. g. gorilla): A stage in the development of self-recognition in a juvenile male?The anomalous position of gorillas (G. g. gorilla) in the capacity for self-recognition remains puzzling. The standard measure of self-recognition is Gallup’s (1970) mark test that assesses an individual’s ability to recognize its altered image in a mirror following the application of paint marks to visually inaccessible areas. Here, the results of a small-scale pilot study are presented, utilizing video playback through a television monitor, to examine behavioural differences indicative of developing self-recognition. The behaviors of four Western lowland gorillas at Bristol Zoo, UK were observed while watching a TV screen during five conditions: blank screen, white noise interference, footage of unfamiliar gorillas, self previously recorded, and self-live. Differences were predicted in the frequency of the gorillas’ observed behaviors when viewing each of the conditions: specifically, that there would be more visual inspection, contingent body and facial movements, and self-exploration in the self-recorded and self-live conditions compared to the other conditions. These predictions were partially supported. No agonistic or fear responses were observed and self-exploration was only seen in the self-live condition. During live playback, contingency-checking movements and self-exploration of the mouth were observed, particularly in the youngest gorilla, providing important video evidence of a close parallel to the mouth exploratory behavior witnessed in self-recognizing chimpanzees. On the basis of these preliminary findings of differentiated spontaneous behaviors, a tentative framework is proposed for categorizing gorillas according to levels of developing self-recognition along a continuum.
-
The cerebral rainforest: How the aftermath of the discovery of the gorilla influenced literature and culture, and altered evolutionary understanding and racial theory in the nineteenth and early twentieth centuries‘The Cerebral Rainforest’ is a study of the gorilla’s considerable influence in literature, culture and science in the Nineteenth and early Twentieth Centuries. It charts the gorilla’s troubled history with mankind and the thinning barriers between the two species – the title refers to the existence of a primal self, buried within in the human brain, which, in some of the works analysed in this dissertation, come to light when faced with gorillas or gorilla-like creatures, ultimately leaving us as wild and exposed as they are. It seeks to establish and understand the image built up around the gorilla during this time, and why it was – and has to some extent remained – a figure all at once terrifying and magnificent, unsettling in its proximity to us. It will engage with evolutionary and racial theories influenced by these animals. The dissertation is therefore divided into three primary chapters, along with an introduction and conclusion, which each deal with a primary focal point – the first chapter; ‘Deep Jungle’, deals with the initial discovery of the gorilla, Nineteenth Century accounts of hunting, the troubled figure of Paul du Chaillu and all those he influenced. The issues explored in this chapter will lead on to the second; ‘A World of Possibility’, which will focus on Nineteenth and early Twentieth Century speculative science fiction and fantasy. The third chapter; ‘The Inner Ape’, will explore the disturbing rise of scientific racism brought about by the breaking down of barriers between animal and human. Ultimately, the dissertation will explore the effect the gorilla had on humanity as a whole – and the unfortunate repercussions this double-edged relationship had on the gorilla.
