Many researchers, including Haidt et al., 1997, have shown that people feel disgust mainly to animals, including people, animal waste products, items that show resemblance to any of those, and lastly, anything that has come into contact with the former. Other elicitors of disgust are sexual deviance, bodily violations, poor hygiene, as well as contact with death. The fact that something is “disgusting” means that we have a strong internal urge to avoid it, so in terms of animal and food products, this would have been partly to avoid pathogens. Fundamentally, disgust is a food rejection emotion, but over time, disgust elicitors have developed from many other cultural, social and moral domains (Rozin et al, 2008).
Why do people find insects more disgusting than bigger animals?
Insects are often found in large groups, they have 6 legs, are often wiggly and move very quickly. In other words, compared to the sight of a larger mammal like a cow or chicken, insects could be considered to look “very animal- like”. This might help explain why we would find the idea of eating them disgusting (Haidt et al.,1997).
Insects are also more similar looking to bacteria and parasites, which are known to spread filth and disease, some of the core disgust triggers. Furthermore many insects live in garbage, and the thought of cockroaches rushing out from the sewer will induce disgust in most people.
The association to sexual deviant behavior may also play a role in why we feel disgust. Insects like grasshoppers and flies can be seen in massive swarms in summer, copulating in midair. This induces the feeling of “flying orgies”, and hence, evokes feelings of disgust (Lockwood, 2013).
It has been argued by Haidt et al.,1997, that these disgust- eliciting events remind people of their animal nature. People in most cultures have a need to set themselves apart from animals, both in terms of physical and symbolic boundaries.
The origins of disgust and why it was beneficial
Unlike many animals who instinctively know what to eat, humans are omnivores and must learn what to eat. The advantage of being an omnivore is the flexibility and adaptability this brings, but on the downside, there is an increased risk of consuming toxic ingredients. An omnivore will always explore and study new foods, but apply scrutiny before they taste. This is why people are “neophobic”, meaning vigilant about new foods, in particular animal foods (Haidt et al., 1997).
Haidt et al., 1997, have tried to show how the emotion of disgust has developed from helping humans to know what to eat in the world around them, to later, what to do in the cultural context of the world (Haidt, Rozin, McCauley & Imada, 1997).
Evolutionary reasons for disgust
One factor, which might explain why we experience disgust at the sight of insects, and less so for bigger mammals, has to do with the history of our farming traditions. Traditionally, the wild animals, which would give the “biggest return” when farmed on a small scale, were bigger mammals like cows, sheep, pigs etc. These animals had a calm nature, so were easy to control, they would have a lot of meat on them, and have a herd mentality. Their skin could also be used for clothing, tools etc. (Terney, 2015).
None of this can be said for insects, which might be why the interest to farm them did not catch on initially. With increased urbanization, people also have less and less contact with nature, so are not exposed to more unfamiliar animals in their natural habitat, on a regular basis. There is a difference in seeing a beetle on a beautiful wild flower, than seeing it rushing across your kitchen table.
Secondly, we are surrounded by bacteria and parasites, which share strong resemblances to insects. The former are transmitted through contact with animals, their waste products etc. Throughout history people have died in millions from diseases transmitted this way, so it is a possibility that disgust has evolved through natural selection. In other words, people who were more sensitive to disgust, would have an evolutionary advantage as they would be less likely to be “contaminated”(Haidt et al., 1997).
Societal reasons for disgust
The theory of biological and evolutionary reasons for disgust has its limitations, as children are not born displaying feelings of disgust. Disgust develops in children during their toilet- training years, with feces being the main, as well as universal disgust trigger. The severity of toilet training, as well as the parents’ apparent revulsion displayed in response to changing the diapers etc., are likely to influence sensitivity to disgust (Rozin, Fallon & Mandell, 1984). Note how children before this age can be found curiously playing with insects and putting them in their mouth, without displaying any feelings of disgust.
Interestingly, Malson, 1964, as seen in Haidt et al., 1997, studied 50 feral children (children who have lived isolated from human contact from a very young age), and found that none of them had developed any feelings of disgust. Hence societal factors may be more important than biological factors.
Cultural differences in terms of disgust are present but very small compared to family context (Rozin, Fallon & Mandell, 1984). Rozin showed that there is a small but positive correlation for food preferences between parents and their children, within a culture. He demonstrated an even larger correlation in terms of disgust and contamination sensitivity. In fact, the children showed approximately the same attitudes and preferences to their parents in this area.
Therefore it seems that genetic as well as early environmental factors play a key role in the development and sensitivity to disgust (Rozin, Fallon & Mandell, 1984).
Trace contamination refers to a disgusting item coming in contact with an acceptable food, and therefore leaving the acceptable food unacceptable (even if the offensive object has only come into contact with the acceptable food for a brief moment). This indicates that disgust is not mainly about preventing bad tastes, but rather has to do with a more complicated idea of “offensiveness” (Haidt et al., 1997). Linking this to the idea of eating insects, people are hesitant not because they expect the insects to taste bad based on the insects’ appearance, but because of anxiety about “what it is”, or “where it has been”. Trace contamination is universal and cross- cultural across grown ups (Rozin, Fallon & Mandell, 1984).
Trace contamination does not appear in children before the age of about 7. The reason for this might be both because of a certain level of cognitive development, as well as by an earlier establishment of a category of disgust.
The moral element
People who are vegetarians for moral reasons find meat more disgusting than people who are vegetarian for health reasons. However the course of moralization is reversible. In other words, something which was previously seen as immoral can be seen as neutral or moral (Rozin, 1999). This is very interesting as it indicates that people who are vegetarian for health reasons could be more easily persuaded to eat insects.
The feelings of disgust have developed as a defense against threats in the physical, societal and moral world. Some disgust triggers like disgust to animals, other people and waste products, are universal across cultures. Other triggers of disgust have developed over thousands of years, possibly as evolutionary defense mechanism. It has been discussed why insects elicit stronger disgust emotions in many people than bigger animals, and why these emotions would have, once upon a time, been beneficial. There seem to be both biological and societal reasons for disgust. The good news however is that these emotions are reversible, so following is a brief discussion on how Psychologists could use this knowledge to achieve changes in people’s behavior and emotions in terms of eating insects.
Family context was shown by Rozin, Fallon & Mandell, 1984, to be a big factor in terms of disgust. In other words: children observing and imitating the feelings of disgust elicited by their parents. This shows the importance of parent’s behavior and parenting style towards their children, and is something that should be addressed by behavioral psychologists. Over time and with training, disgust triggers towards for example insects, could change, and the sight of insects and the thought of eating them would no longer elicit disgust responses. Once a generation has changed their conception of eating insects, the effect would be duplicated for the following generation.
Trace contamination (referring to an acceptable food having come into contact with an unacceptable food hence leaving all the food unacceptable) seems to be more about a taught, cognitive idea of “offensiveness”, rather than about the actual taste of something. The fact that the effect of trace contamination does not appear in children before the age of seven, means that it could be stopped before the child acquires it. This explains why a third of the world’s population currently eat insects, as they have never been taught that eating insects is ‘disgusting’. For adults, educating them about what insects are, how they are farmed, what their health benefits are etc., could help them overcome their fear of “what insects are”, and make them see insects in the same way they see other sources of protein.
People are very visual, and most of the meat displayed in supermarkets has been packed and processed so it does not resemble the entire animal. In the same way as many people would be put off by seeing a whole cow displayed as “meat”, whole insects induce the same uneasiness. Going forward, introducing people to ‘hidden’ and smaller amounts of insects in food products, could be a way to convince them to try the product. The same principle applies when sushi was introduced in the Western world in the 80’s, and sushi has now become as mainstream as pizza and burgers.
Lastly, the fact that even emotions of morality can be reversed, means that people who are vegetarians or vegans for moral reasons, could change their attitude about eating meat, and hence insects. Insects contain many nutrients such as all essential amino acids and have a high protein content, which many vegetarians are lacking. The fact that insects are further down the ‘food chain’ than larger animals, and don’t have the same cognitive levels, could be used as a convincing argument for vegetarians and vegans to change their attitudes towards eating insects.
To conclude, we need behavioral and cognitive psychologists to collaborate and devise educational training methods to change people’s attitudes about eating insects. The studies that have been done clearly demonstrate that this is a possible task, which poses different challenges in terms of the education needed for children compared to adults.
Haidt, Rozin, McCauley & Imada, The Relationship between Disgust & Morality, 1997, Psychology and Developing Societies 9, 1.
Lockwood, J., How to Cultivate Disgust, Oct. 29 2013, http://www.theatlantic.com/health/archive/2013/10/how-to-cultivate-disgust/280858/
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Terney, O., Bionyt Videnskabens Verden, N. 162, April 2015