Revulsion in chimpanzees: health maintenance through avoidance of biological contaminants

10.7287/peerj.preprints.1851v1 ◽

2016 ◽

Cited By ~ 1

Author(s):

Cecile Sarabian ◽

Andrew J. J. MacIntosh

Keyword(s):

Helminth Parasites ◽

Health Maintenance ◽

Pan Troglodytes Troglodytes ◽

Avoidance Behaviors ◽

Behavioral Avoidance ◽

Biological Contaminants ◽

Olfactory Stimuli ◽

Tactile Cues ◽

Sources Of Infection ◽

Parasite Avoidance

Many major human infectious diseases are transmitted via bodily products such as feces, blood, semen, and saliva. Such contaminants are also known disgust elicitors among humans. From an evolutionary perspective, revulsion in humans is hypothesized to have evolved to protect us from the risk of contracting disease; sensu the Parasite Avoidance Theory of Disgust. To investigate whether chimpanzees are sensitive to these potential sources of infection, we conducted feeding-related experiments to elicit avoidance behaviors in captive chimpanzees (Pan troglodytes troglodytes, N=20-42; sex ratio=1; 27±9 years-old) at the Centre International de Recherches Médicales de Franceville, Gabon. In the first set of experiments, we tested for feces-avoidance behaviors by presenting target individuals with food rewards in conjunction with visual, olfactory and tactile cues of chimpanzee feces. In a second experiment, the same individuals were presented with olfactory stimuli of blood, semen, and rotten meat. In all experiments, chimpanzees expressed some degree of behavioral avoidance, manifest as refusals to feed, increased latencies to feeding, or maintenance of greater distances from contaminants relative to control substrates. We are now in the process of testing whether behavioral tendencies observed toward these contaminants coincide with individual health markers, including current levels as well as historical records of infection with bacterial, protozoan and helminth parasites. We predict that individuals with greater tendencies toward avoidance of such contaminants, possibly representative of revulsion, to be characterized by better general health than less sensitive individuals.

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Avoidance of biological contaminants through sight, smell and touch in chimpanzees

Royal Society Open Science ◽

10.1098/rsos.170968 ◽

2017 ◽

Vol 4 (11) ◽

pp. 170968 ◽

Cited By ~ 19

Author(s):

Cecile Sarabian ◽

Barthelemy Ngoubangoye ◽

Andrew J. J. MacIntosh

Keyword(s):

Experimental Evidence ◽

Pan Troglodytes ◽

Comparative Research ◽

Adaptive System ◽

Parasite Infection ◽

Avoidance Behaviour ◽

Pan Troglodytes Troglodytes ◽

Sensory Modalities ◽

Biological Contaminants ◽

Parasite Avoidance

Avoiding biological contaminants is a well-known manifestation of the adaptive system of disgust. In theory, animals evolved with such a system to prevent pathogen and parasite infection. Bodily products are human-universal disgust elicitors, but whether they also elicit avoidance behaviour in non-human primates has yet to be tested. Here, we report experimental evidence that potential exposure to biological contaminants (faeces, blood, semen), as perceived via multiple sensory modalities (visual, olfactory, tactile), might influence feeding decisions in chimpanzees ( Pan troglodytes troglodytes )—our closest phylogenetic relatives. Although somewhat mixed, our results do show increased latencies to feed, tendencies to maintain greater distances from contaminants and/or outright refusals to consume food in test versus control conditions. Overall, these findings are consistent with the parasite avoidance theory of disgust, although the presence of biological contaminants did not preclude feeding entirely. The avoidance behaviours observed hint at the origins of disgust in humans, and further comparative research is now needed.

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Beggars Can’t Be Choosers: Disgust as a Cue and Signal of Social Status

10.31219/osf.io/wrvgh ◽

2019 ◽

Author(s):

TCU Hill Lab

Keyword(s):

Social Status ◽

Impression Management ◽

Person Perception ◽

Disgust Sensitivity ◽

Sensitivity Functions ◽

Avoidance Behaviors ◽

Behavioral Avoidance ◽

Naturally Occurring ◽

Pathogen Avoidance ◽

The Relationship

Disgust is a costly emotion, as it prompts behavioral avoidance of stimuli and conspecifics perceived to pose a contamination threat, limiting the number of mating, caloric, or affiliative opportunities available to a person. Disgust sensitivity should vary based on the costs of reducing the potential options available for solving a given adaptive challenge, being higher for those who have more options, and lower for those who have few. Given that social status plays an important role in modulating the costs associated with pathogen avoidance behaviors, we predicted that social status would be conceptually linked to disgust sensitivity in ways that have important implications for person perception. Findings reveal that disgust sensitivity functions as an important cue to target’s social status, and that targets with naturally occurring cues of high (vs. low) social status are perceived to experience greater disgust. In addition to serving as a cue to social status, findings reveal that disgust may also be used to signal social status to others, particularly when one’s status is threatened. By establishing a conceptual linkage between disgust sensitivity and social status, the current research provides important insights regarding the relationship between these two constructs and highlights the important role these variables play in processes of person perception and impression management.

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