To summarize where we are in our reflection, the presence of pathogens activates the behavioural immune system (BIM) and leads to greater rigidity in social norms (hygiene, nourishment, sexuality) as well as a greater aversion for those who break them (See blogs 1 and 2). So, does the BIM have a role to play in establishing and maintaining prejudices against certain marginalized groups? Not only is the answer yes, but the BIM has a leading role to play for prejudices with regard to people who are obese, disfigured, handicapped, seniors, foreigner and homosexuals (Aarøe& al., 2017; Ackerman & al., 2018; Fincher et al., 2008; Karinen & al., 2019; Kiss & al., 2020; Lai & al., 2014; Murray & al., 2013; Navarette & al., 2007; Terrizzi & al., 2013; Vartanian & al., 2016).


The BIM interprets the difference of these people as being possible signs of pathogens (or the non-respect of social norms), fostering a sense of aversion and therefore a desire to avoid (Ackerman & al., 2018; Schaller & al., 2011). However, if you were to tell me that these differences are far from being synonymous with diseases, you would be right. That is why they are prejudices that are spoken leading them to become a pre-reasoning intuition. The BIM has evolved partially to avoid us entering into contact with someone who carries a communicable disease. He must therefore make quick judgements on people he doesn’t know in order to determine if we can enter into contact with them or not (Ackerman & al., 2018). Moreover, he has a small trend towards avoidance (Schaller & al., 2011). He prefers to make a mistake and recommend avoidance than to make a mistake and recommend contacts leading to the transmission of a potentially fatal disease. You now understand why he is filled with prejudices, but also how we can find ourselves with avoided, marginalized or systematically excluded communities. But in this context, could the BIM lead to violence against these communities?

The BIM, violence and exclusion

Fortunately, it appears that this is unlikely. The simple explanation is that violence involves entering into contact with others, whereas aversion for others activated by the BIM encourages avoidance (Aarøe & al., 2017; Pond & al., 2012; Terrizzi & al., 2013). Therefore, activation of the BIM is less related to verbal violence, less physical violence and less domestic violence (Pond et al., 2012). Nevertheless, once the aversion for others generated by the BIM is combined with a sense of injustice or anger, it could lead to a motive for aggression (Terrizzi & al., 2013). However, in general, the BIM provokes exclusion rather than violence.

That’s not something to be taken lightly knowing that social exclusion can be as painful as physical violence, both of them activating the same neuronal circuits (Eisenberg & al., 2003). From an evolutionary standpoint, it is logical for exclusion to be as painful since for millions of years our survival depended a great deal on our ability to be included rather than excluded (Leary, 2005).  We are therefore very sensitive to exclusion which would have a negative impact on our four fundamental needs (control, belonging, self-esteem and recognition) in addition to leading to sadness, anger and a reduced sense of happiness (Sandstorm & al., 2017). There’s also the fact that among children, exclusion increases the risk of being the victim of bullying (Parent et D’amours, 2019) with the result that when they are bullied they receive less support from their peers, making them more inclined to blame themselves for the bullying that they are victims of and therefore more inclined to develop anxiety disorders and depression (Garandeau & al.,2018; Sainio & al., 2011; Salmivalli, 2018).

Now that we know that COVID-19 could favour an increase in exclusion and bullying against marginalized communities, a crucial question arises: what can we do? That will be the theme of our next and final blog. To be continued…

Alexandre Baril

Project Manager – Take action! Counter bullying in sports



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We are therefore very sensitive to exclusion which would have a negative impact on our four fundamental needs (control, belonging, self-esteem and recognition) in addition to leading to sadness, anger and a reduced sense of happiness