Periodic Reporting for period 1 - DiseaseRecognition (Selection to outsmart the germs: The evolution of disease recognition and social cognition)
Période du rapport: 2017-02-01 au 2019-01-31
Humans have an unusual strategy for dealing with infectious disease. Instead of avoiding contagious individuals, we provide them with extensive care. This enables us to control the spread of diseases through our population. Surprisingly, we know very little about how care-giving behaviours evolved. Care-giving hinges on a cognitive ability whose evolutionary origins are largely unknown: the ability to recognise disease in others. This project integrates comparative psychology, host-parasite biology, anthropology, and chemical ecology to begin to reconstruct the evolution of disease recognition in the primate order.
Primates are our closest living relatives, and like humans, are known for their social complexity, characterised by learning from others, cooperation, and coalitionary behaviour. The social pressures of managing these relationships are believed to have selected for increased cognitive abilities. However, the frequent, close proximity interactions that these behaviours require also increases the risk of disease transmission, making the ability to recognise disease highly advantageous.
The brain pathways integral to understanding social interactions (social cognition) in primates are likely to also be active in detecting disease symptoms. Subtle differences perceived in faces, voices, and odour may enable primates to not only decode others’ identities, emotions, and intentions, but also detect disease. This could include changes in facial colouration, shape and texture due to fever, rashes, weight loss, or nasal discharge, changes in vocalisations due to coughing, nasal discharge or reduced lung capacity, and changes in odour due to immune activation. Thus, if the detection of social information and disease involve the same brain pathways, then they may have evolved together.
Mandrills are ideal study subjects for this question because they are highly social and engage in complex communication, including striking facial colouration, elaborate vocalisations, and scent-marking behaviours. All of these cues have the potential to communicate health information.
This study integrates state-of-the-art methods from multiple disciplines (parasitology, digital imaging, bioacoustics, odour analysis, and cognition) to accomplish three objectives.
1: Test whether mandrill appearance, vocalisations, and odour signal parasite infections.
2: Test whether mandrills can detect disease via facial colouration, vocalisations, and scent-marks.
3: Test how disease recognition correlates with other types of cognition.
Primates are our closest living relatives, and like humans, are known for their social complexity, characterised by learning from others, cooperation, and coalitionary behaviour. The social pressures of managing these relationships are believed to have selected for increased cognitive abilities. However, the frequent, close proximity interactions that these behaviours require also increases the risk of disease transmission, making the ability to recognise disease highly advantageous.
The brain pathways integral to understanding social interactions (social cognition) in primates are likely to also be active in detecting disease symptoms. Subtle differences perceived in faces, voices, and odour may enable primates to not only decode others’ identities, emotions, and intentions, but also detect disease. This could include changes in facial colouration, shape and texture due to fever, rashes, weight loss, or nasal discharge, changes in vocalisations due to coughing, nasal discharge or reduced lung capacity, and changes in odour due to immune activation. Thus, if the detection of social information and disease involve the same brain pathways, then they may have evolved together.
Mandrills are ideal study subjects for this question because they are highly social and engage in complex communication, including striking facial colouration, elaborate vocalisations, and scent-marking behaviours. All of these cues have the potential to communicate health information.
This study integrates state-of-the-art methods from multiple disciplines (parasitology, digital imaging, bioacoustics, odour analysis, and cognition) to accomplish three objectives.
1: Test whether mandrill appearance, vocalisations, and odour signal parasite infections.
2: Test whether mandrills can detect disease via facial colouration, vocalisations, and scent-marks.
3: Test how disease recognition correlates with other types of cognition.
We collected data on approximately 50 mandrills at the International Centre for Medical Research in Franceville, Gabon. The mandrills live in large groups in huge, naturally forested enclosures. Once per year they are caught for veterinary exams and treated with anti-parasite medications. Our project piggybacked on this veterinary exam, by collecting data before and after the mandrills received the anti-parasite medications. We took photographs, recorded vocalisations, and collected odour and faecal samples before and after the treatment. We are currently analysing the data to determine if and how the mandrills’ facial colouration, vocalisations, and odour signals changed as a result of the anti-parasite medications. In the next phases of the project, we will test whether mandrills use these cues to recognise when other mandrills are infected with parasites and whether this recognition is associated with other cognitive abilities in mandrills.
We are disseminating our results as we produce them. We have shared them with the academic community through articles in well-respected scientific journals and presentations at international meetings. We have shared them with the public through public websites, talks, and media coverage of the work.
We are disseminating our results as we produce them. We have shared them with the academic community through articles in well-respected scientific journals and presentations at international meetings. We have shared them with the public through public websites, talks, and media coverage of the work.
This project opens a new line of research into how the ability to recognise disease evolved and whether this ability is associated with the ability to process social information. This knowledge can help us understand disease dynamics in wild primates. This project also enables us to better understand ourselves by exploring the evolution of disease recognition, and ultimately, how disease recognition may facilitate care-giving for the sick in humans.
This study benefitted Europe in several ways. (1) It raised Europe’s research profile by forging new and lasting international collaborations. These links put Europe at the centre of a project with global connections, including the UK, the Czech Republic, Gabon, Germany, and the US. This network facilitates a sustained exchange of ideas, stimulates new synergies, and contributes to maintaining a vibrant research environment in Europe. (2) The project increases Europe’s competitiveness by creating new multidisciplinary knowledge. This is the first study of the relationship between disease recognition and cognition. As such, it creates new knowledge at the interface of animal behaviour, parasitology, and evolutionary psychology, ensuring that Europe takes a lead role in these fields. (3) The fellowship contributed to growing the European science base. The fellow served as an ambassador for research through her websites and talks. She has also mentored students and field assistants, contributing to the development of the next generation of scientists in Europe.
This study benefitted Europe in several ways. (1) It raised Europe’s research profile by forging new and lasting international collaborations. These links put Europe at the centre of a project with global connections, including the UK, the Czech Republic, Gabon, Germany, and the US. This network facilitates a sustained exchange of ideas, stimulates new synergies, and contributes to maintaining a vibrant research environment in Europe. (2) The project increases Europe’s competitiveness by creating new multidisciplinary knowledge. This is the first study of the relationship between disease recognition and cognition. As such, it creates new knowledge at the interface of animal behaviour, parasitology, and evolutionary psychology, ensuring that Europe takes a lead role in these fields. (3) The fellowship contributed to growing the European science base. The fellow served as an ambassador for research through her websites and talks. She has also mentored students and field assistants, contributing to the development of the next generation of scientists in Europe.