Which animals do humans fear most, and why? To answer these questions and better understand biophobia (the fear of animals), French researchers conducted an online study with more than 17,000 participants from every continent.
The protocol was simple and effective: photos of animals were displayed and they had to choose the one they feared the most. In this way, Karl Zeller of the Éco-Anthropologie laboratory (CNRS/MNHN) and his colleagues were able to classify 184 species of mammals, reptiles, birds, arthropods, and amphibians on a "fear scale." Their study, published on March 10, 2025, in the journal People and Nature, reveals justified fears but also others, more irrational, signs of a disconnection with nature. Interview with Karl Zeller.
Sciences et Avenir: Why is it important to better understand biophobia?
Karl Zeller: A better understanding of biophobia means better understanding negative human perceptions of nature, flora, and fauna, their origins, and how they develop and persist. This is important because, by nature, they are extreme and can lead to health problems and anxiety disorders.
Then, species that generally induce these strong and negative emotions (fear, disgust, aversion) are disliked and may be less well protected than charismatic species. Better understanding biophobia therefore allows us to discuss our relationship with the world, with nature, with fauna and flora.
“A phobia is an exacerbated, irrational and disabling fear.”
From an evolutionary perspective, what does this fear achieve when it is properly directed?
By definition, biophobia cannot be properly managed. A phobia is an exacerbated, irrational, and disabling fear. It is not an adequate fear that allows one to escape threats and stay alive. It primarily reflects a growing aversion and disconnection of society from nature.
In your study, you indicate that photos of dangerous animals elicit a frequent and rapid feeling of fear. But you also explain that harmless animals also reach high levels of fear. How can you explain this result?
The fear of harmless animals is irrational; it cannot be explained by evolution. Therefore, another explanation must be found. For example, participants who were afraid of spiders reported fearing being hurt, killed, or even eaten! This clearly illustrates the absurdity of this fear.
These results stem from a lack of understanding of animals, often fueled by the media and films, coupled with a growing disconnection with the natural environment. These fears become entrenched and become realities, especially among children. These erroneous representations of nature are then passed down from generation to generation. And since there is no confrontation with an ecological reality, such as encounters with animals in their natural habitat, there is no change.
In this study, we note an irrational fear of certain non-venomous spiders or snakes, but we can also see the opposite phenomenon. Fears that could be rational about dangerous animals such as lions or tigers become imbued with socio-cultural beliefs, think of Simba from Lion King. Evolutionarily justified fears can also be influenced and weakened in this way.
"There are immediately recognizable danger signals."
Based on your results, did the most feared animals deserve their place?
Yes, indeed. Millions of years of evolution have led us to develop abilities to recognize characteristics associated with dangerous animals. There are immediately recognizable danger signals, such as geometric shapes and bright colors. Many animals, and even children, tend to avoid triangular shapes and bright colors!
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