How would you feel sharing a toothbrush with the postman? What about drying your hands on a towel with a yellowish stain? Or, by touching the gooey larvae of unknown insects?
Your answer will probably be the same as anyone: disgust. But why?
According to researchers at the London School of Hygiene and Tropical Medicine, this reaction may be common to the entire human species and play a key role in its evolution: disgust would be a protection mechanism against the threat of infectious diseases. The idea was presented in an article published on January 6 in the British magazine. Proceedings B, edited by the Royal Society.
To reach this conclusion, scientists tested and confirmed that situations associated with the risk of disease transmission - such as sharing a brush with the postman - would be considered more disgusting than apparently safer ones - such as using a spouse's brush or From a brother.
The study was conducted among 40,000 Internet users, who evaluated a series of images published on a website by the British media group BBC. The volunteers rated the photos according to a 'disgust scale' from 1 to 5. The reactions confirmed the initial hypothesis: the participants acted according to the logic of protection against disease risk.
Images that resembled body fluids and photos of infected wounds were considered, respectively, to be more disgusting than blue fluids (unusual in nature) and aseptic wounds, for example. "We observe a universal response pattern: People feel disgust to protect themselves from living objects and beings that pose a risk to their health and, therefore, to the very survival of the species," celebrates Robert Anger, one of the study's authors. He underscores the fact that women, "most responsible for protecting the younger generation," feel more disgusted than men: "all seven images associated with some risk of disease were considered more disgusting by women, which confirms the role evolution of that feeling. "
The researcher also stated that the study contemplated different cultural groups, because it was conducted via the internet. "As much as most of the answers came from Europe, we had access from 165 different countries."
According to him, disgust would be a behavior transmitted by society to individuals to avoid risky situations. "We can teach children to disgust a face or a bruise, for example, but we can hardly teach them to be disgusted with a flower," he explains. "Human beings would be prepared to learn certain behaviors and predisposed to reject others."
Asked about people who are disgusted by risk-free situations, such as some kind of food, for example, Anger explains that there are behaviors strongly influenced by previous experiences. "It's possible someone is disgusted with honey," he admits. "But this case does not fit the model suggested because it is probably associated with personal trauma."
Adapted from: Science Today Magazine - Julio Lobato (18/02/04)