The Uncomfortable Link Between Animal Cruelty And Human Out-Group Prejudice

An psychological exploration of the available literature on the subject of speciesism, social identification, and outgroup prejudice

While human identity and outgroup studies have long existed at the forefront of academic discussion, it is only very recently that the relevance of the human-to-animal relationship has made its way into the conversation.

The acceptance of new research and related theoretical framework into some of the world’s top psychological journals (e.g., Amiot & Bastian, 2015; Caviola, Everett, & Faber, 2019), is a result of the initial stages of recognition that there is, indeed, more to learn when it comes to the psychological mechanisms that underpin the establishment of social identity and outgroup prejudice.

Furthermore, there is increasing evidence to suggest that by acknowledging the processes that govern the unique state of human indifference towards the suffering of animals, we may realize the comparability of our treatment of animals, with our treatment of other vulnerable members of society.

“The separation of ‘us’ and ‘them’ creates a false picture and is responsible for much suffering. It is part of the in-group / out-group mentality that leads to human oppression of the weak by the strong as in ethnic, religious, political, and social conflicts”

— Marc Bekoff

Thus, the consequences of the research discussed within this article could prove extremely valuable to a wide range of disciplines, overlapping with topics such as immigration and slavery studies, in-group-out-group relations, policy making and many, many more.


The role and importance of social identification in psychology was first discussed by psychologists Tajfel and Turner (1986) with the conclusion that people do not merely consider themselves in the context of individual people, but that group membership and social identification played a large role in self-concept, also.

What this means is that societal classifications such as being ‘American’ or ‘Muslim’ or ‘middle-class’ have a vital connection in how we perceive ourselves, others, and the interaction between the two.

McFarland, et al. (2012) suggest that our superordinate identities can include any and all possible categories, and be scaled up or down resulting in critical implications for the ways in which we treat others.

The how and why of these implications can be better understood through the work of Adler (1927) and Maslow (1954) who originally theorized that a key pillar of self-actualization involves an individual’s ability to identify with, and subsequently extend their concern for, humanity as a whole (Reysen & Katzarska-Miller, 2018).

Having a wider ‘net’ of identification, so to speak, is also associated with a range of positive qualities, including the willingness to control prejudice, and the experience of increased solidarity with animals (Stürmer, et al., 2016; Lee, et al., 2015).

Despite these findings, there is a well-observed tendency for humans to dismiss their situation within the animal kingdom, drawing a man-made line of separation between humanity and the fauna of the world (Arndt, et al., 1997).

Research suggests that it is within this widespread tendency to reject social identification with animals, that the roots for human-to-animal discrimination, namely speciesism, exist (Dhont & Hodson, 2020).

Speciesism is a concept best defined as the philosophical phenomenon of morally discriminating against individuals on the basis of their species membership, and although examples of speciesist behaviours within society are almost as numerous as the species of animals themselves, the consumption of animal products (i.e. meat, dairy, and eggs) is often the one most commonly cited within the literature (Singer, 1975).

In this context, animal consumption is to be considered an act of speciesism based on the reasoning that the individual engaging in this action would not consume other species of animals such as dogs, cats, or humans, for example, thereby discriminating specifically on the basis of species (Caviola, Everett, & Faber, 2018).

This is to say, in summary, that humans find ease of justification for eating certain animals as a result of considering themselves as existing as above, (or at the very least, separately from) animals, despite this, factually, not being the case.

“In their capacity to feel pain and fear, a pig is a dog is a bear is a boy.” — Philip Wollen

Research shows that most individuals will maintain that they love, and wish to protect most animals from inhumane treatment, while simultaneously choosing to consume their flesh (Bastian & Loughnan, 2017).

The so-called “meat paradox,” as it is often referred to, thus reveals psychological and behavioural inconsistencies that lend themselves to the notion that there exists an interesting form of cognitive dissonance taking place within the context of identification (Bastian & Loughnan, 2017).

When these results are examined in conjunction with one another, there is increasing reason to believe that participant attitude is not always an accurate indicator of biased action.

This is because prejudice and harmful behaviour do not necessarily equate as demonstrated by the meat-paradox, above.

What these theoretical explanations fail to address, however, is to what extent the same mechanisms may be implicated in the holding of discriminatory perceptions towards human outgroups, of which, the ramifications would be immense and largely unprecedented within the field of psychology.

Human Social Identification with Animals


There is a dimension identified within the literature on social identity, known as solidarity, that may prove useful in supporting the argued relevance of the human-to-animal (HTA) relationship in human-to-human (HTH) psychological application (Amiot, et al., 2017; Leach, et al., 2008).

In social psychology, an individual’s score in measures of solidarity represents their bond and commitment to fellow group members, creating a range of sociological consequences when examined in the context of wider populations and groups, similar to those previously discussed (Leach, et al., 2008).

In order to explore this concept’s explicit relatedness to the HTA relationship, eight studies involving a mixture of correlational, experimental and longitudinal designs were conducted by Amiot and Bastian (2017) using established scales and measures for solidarity.

Following the collection of data, it was found that higher levels of reported solidarity with animals predicted more positive attitudes and behaviours towards animals, even when the implied loss of human privilege or valuable resources was considered.

Typically speaking, the personal engagement in acts of speciesism is shown to result in a decreased experience of solidarity with the broader category of the animal kingdom (Dhont, et al., 2016). After all, it becomes problematic psychologically to rationalize the commodification of a group that one strongly identifies with and feels bonded to.

Instead, by creating an environment that is conducive to the increased consideration of solidarity with animals, as observed in study 7 by Amiot and Bastian (2017), it becomes increasingly difficult for a prioritization of human gratification over animal welfare to be made, thereby explaining the difference in attitudes, even at the expense of potential human pleasure and/or gain.

These studies outline more overtly the phenomena touched upon by previously established theories of speciesism, but also go the one step further in providing evidence that the relationship can go both ways.

In this sense, not only can it be argued that the discrimination of certain species of animal is perpetuated by the failure to identify with them, but that in the case of an orchestrated effort to facilitate human identification with animals by way of solidarity, species-based discrimination can be significantly reduced.

A core limitation of these findings, however, is that speciesism was operationalized solely via a scale measuring participants’ self-reported attitudes, and not by any meaningful assessment of their actions outside of the experiment, highlighting a consistent gap within the available literature.

Building onto this, study 3 by Amiot and Bastian (2017), in particular, concluded that participants who scored higher in solidarity with animals, subsequently scored lower in human out-group prejudice, the desire to dominate human minority groups, as well as the tendency to hold negative attitudes towards people they were in disagreement with.

Dhont, Hodson and Leite (2016) had previously published research in support of this inference, concluding that the desire for group-based dominance underpins biases towards both non-human animals, and human out-groups, alike.

Important to note as a potential constraint of this phenomenon, is that when humans and animals faced a conflict of needs, or a competition for resources, the link between solidarity with animals, and the increased acceptance towards out-groups, became non-apparent within the experiment (Dhont, et al., 2016).

This condition may allude to the presence of evolutionary mechanisms designed to ensure survival of individuals and the in-groups they belong to.

What’s more, is that Dhont, Hodson and Leite (2016) found that meat-eaters, when compared to vegetarians and vegans, scored significantly lower in measures of solidarity with animals, establishing a direct negative correlation whereby the more meat a participant consumed, the lower they scored on measures of solidarity, and vice versa (Dhont, et al., 2016).

Despite it being an uncomfortable idea to swallow, it is thereby suggested that there may be a link between social identification, the engagement with speciesist acts such as meat consumption, and the perception of human out-groups and minorities in the world we live in today.

Indeed, it follows, that if the way humans both view and act in the human-to-animal relationship is evidenced to have an effect on their treatment of human outgroups, then perhaps human identification as, and with, animals, reveals more about human-to-human relationships than what is currently completely understood.

This conclusion is upheld by a psychological framework that acknowledges that the locating of subgroup identities within the context of an overarching, shared superordinate identity (in this case, ‘human’ as a subgroup of the larger category: ‘animal’) allows for higher levels of social harmony and perceived oneness (Maslow, 1954; Hornsey & Hogg, 2000).

Here, the relevance of examining performance and action-based indicators of solidarity with animals, such as engaging in speciesist acts, is largely substantiated, yet not explicitly addressed.

The addition question remains as to which specific areas of human outgroup attitudes may be impacted, and in turn what cognitive processes may lie at the ideological core of these issues.

Similarity as a Second Dimension of Social Identification

In addition to the relevance of solidarity attitudes in determining human identification with animals, the concept of ‘similarity’ suggests that the greater the perception of human to animal similarities for an individual, the greater the result of a reduced desire to assert human superiority over them (Amiot, et al., 2017).

Indeed, research has shown that placing a direct emphasis on how animals are similar to humans, actually results in a significant decrease in the participants’ likelihood of endorsing acts of speciesism (i.e. the use of animals as means for human ends), subsequently indicating higher levels of social identification with animals as an entire group.

Similarity conditions have also been found to result in participants’ increased tendency to express moral concern to human out-groups, suggesting a parallel between treatment of animals and minority groups (Bastian, et al., 2012).

Researchers Costello and Hodson (2010), reported an increase in the humanization and favourable perception of immigrants when utilizing an ‘animals are similar to humans’ framing condition.

This can be theorized to have occurred as a result of facilitating key processes cognitive processes that are, in turn, responsible for the reduction of prejudicial sentiment towards immigrants.

In orchestrating individuals to perceive the similarities of animals when compared to humans, there exists, as a by-product, the promotion of a re-categorization of the participants’ established in-group classifications, whereby empathy is able to be extended to the outgroup, creating a natural reduction in negative biases towards them.

Future academic consideration of the concept of similarity existing as a second dimension of social identification, would therefore contribute to a more well-rounded understanding of how the psychological mechanisms involved in the formation of bias operate.

Out-group Prejudice

Social Dominance Orientation

The enforcement of norms by a dominant group and/or groups has been an intrinsic component of societal organization since the beginning of civilization; This phenomenon is occurring at both a higher, systemic and institutionalized level, as well as at the level of the individual, i.e. personal prejudice towards out-groups (Hodson, et al., 2017).

A concept and psychological metric known as Social Dominance Orientation, or SDO, details the ideological belief system of endorsing inequality and group-based dominance with the overarching objective of preserving a social hierarchy (Pratto, et al., 1994).

An individual who scores highly in this trait seeks to rationalize and morally legitimize the devaluing of out-groups in order to allow for the maintenance, or potential implementation, of oppressive policies that, in turn, may benefit the desired in-group(s).

What’s more, is that the scope of this research can be broadened and theoretically assessed in its ability to be applied to the human-animal relationship (Pratto, et al., 1994).

Costello and Hodson (2010) suggest that SDO is an accurate predictor of an individual’s propensity to believe humans are superior to animals, a sequitur inference of existing research on prejudice and superiority.

Further to this, Dhont, et al. (2016) found that after accounting for SDO in their study, the correlation between ethnic prejudice and speciesism became statistically non-significant, identifying SDO as the underlying connection between the two.

These results were verified in a study of a similar nature explicitly designed to determine the association between homophobia and speciesism. Once more, after accounting for scores of SDO, the significance of the relationship between the two variables became absent (Everett, et al., 2019).

By establishing SDO as the key factor that underpins multiple forms of outgroup devaluation and discrimination — including speciesism — the idea that the way humans interact with, and perceive other animals has no correspondence to the way humans interact with one another altogether loses its veracity.

In order to fully test this association, Dhont, and Hodson (2020) recently developed and proposed the Social Dominance Human-Animal Relations Model (SD-HARM).

This model accounts for the significant positive relationship between ethnic outgroup prejudice and speciesist attitudes, and implicates SDO as the trait responsible for exploitative tendencies towards both human and non-human animals.

Support for this conclusion was upheld by the subsequent meta-analytic integration that took place across the varying studies. A key limitation of SD-HARM, however, is the remaining question of whether or not individuals scoring high in SDO experience an intrinsic desire for dominion over animals, or if this outcome is perhaps merely a consequential by-product of their preference for human intergroup inequalities.

Racism, Sexism and Ageism

For as equally pervasive and ever-present as speciesism is to racist, sexist, and ageist behaviours within society, it can come as somewhat of a surprise that psychological research has only just begun to connect the dots between violence against animals and human-to-human relations.

One of the first individuals to do so was feminist theorist, Carol Adams, in, “The Sexual Politics of Meat.” In her book, Adams explores the similarities between the subordination of animals and women within Western culture, particularly where their respective reduction to mere objects of food and sex is concerned, by way of objectification, fragmentation, and consumption (1990).

Despite the controversial nature of the publication itself, its allusion to underlying psychological and socio-political factors as driving of the mechanisms upon which both human and non-human animal discrimination can occur is illustrative of the necessity for further research examining the relevance between the two.

Scientific recognition of a link between (human) outgroup attitudes was first provided by theoretical framework first established by research psychologist Allport (1954), which was later expanded upon by Hodson and Dhont (2015); this is what is conceptually known as generalized prejudice.

The concept of generalized prejudice suggests that an individual who is found to have prejudice against a single race, gender, or outgroup, is likely to have prejudice towards other races, genders and outgroups, etc., in what is considered an across-the-board outgroup devaluation.

While this theory’s applicability to outgroup studies is by no means novel, its recent extension to the human-animal relationship, is.

For the purposes of this article, it then becomes necessary to examine to what extent speciesism — both practiced, and operationally defined through measures of solidarity with animals — may also be implicated within the framework responsible for the idea that prejudice inevitably begets prejudice.

Investigations into the reason why this phenomenon occurs have pin-pointed SDO as a strong predictor of generalized prejudice, once more indicating a common thread between negative biases towards particular ethnic groups, sexualities, genders, and species (Akrami, et al., 2011; Hodson, et al., 2017; Everett, et al., 2019).

Research by Bergh and colleagues (2016) provided evidence for a stipulation in this theory, in that generalized prejudice may only apply to marginalized/low status groups.

Hence, there exists the possibility for differences across and between cultures, as minority groups differ, naturally, with the sole exception of one group: animals.

Across all societies, non-human animals represent the quintessential low-status group when the depth, duration, and systemic nature of their exploitation for human interest is taken into consideration.

That is to say that they are perhaps the ideal category of individuals upon which to draw conclusions pertaining to the wider spectrum of social dominance and discrimination.

What remains to be addressed, however, is whether or not the same process would hold true in reverse.

In other words, does the human-to-animal relationship actually translate to an increase in gender, age, and race-related biases towards human out-groups and minorities?

In order to adequately assess this, it is vital to combine what is outlined in the previous chapters and consider the implications and foundations of these prejudices more deeply.

Two key theories are explicitly needed to do so: namely, Chain of Being (Brandt and Reyna, 2011), and The Interspecies Model of Prejudice (IMP) (Hodson, et al., 2013).

While Chain of Being outlines the hierarchical system through which individuals determine societal value and consideration, IMP states that the greater the tendency to perceive animals as inferior to humans is, the greater the tendency exists to dehumanize other human outgroups.

These are the missing pieces of the puzzle, so to speak, and help to illustrate the concomitant nature of the human-to-animal and human-to-human relationship.

It was Bandura (1999) who first studied the concept of dehumanization within a sociological context.

It is in conjunction with the theory of Chain of Being — one that positions humans at the very top of the hierarchy of all sentient creatures — that Bandura’s conceptualization can be best understood.

He concluded that when people do harm to others, they experience a moral disengagement through a process called ‘dehumanization.’

Dehumanization is the perception that another individual (or group) is relatively less human than the self (or in-group)(Hodson, et al., 2014).

This perception allows for in-group members to subsequently justify the victimization of those individuals by removing a core element of ‘alikeness’ that might otherwise generate a form of cognitive dissonance/discomfort for them.

It is shown here that processes such as psychological rationalizations and dominance motives may form the center pillar upon which prejudice is formed, and subsequently performed.

“When animals do something noble we say they are behaving “like humans.” When humans do something disgusting we say they are behaving “like animals.”

— Philip Wollen

Costello and Hodson (2014) produced empirical evidence for this theory with their study whereby white children as young as 6–10 were observed to animalistically dehumanize black children.

The experiment featured the assignment of various qualities to a series of photos of both black and white children.

The result was a tendency for the participants to match human-exclusive qualities, such as feeling embarrassed or sympathetic, to the photos of white children, while attributing human non-exclusive feelings, such as being timid or happy, to the photos of black children.

Further to this, research has revealed that white children aged between 5–10 have a tendency to perceive black children as experiencing less pain than themselves (Dore, et al., 2014) not dissimilar to the way Singer (1975) characterized the human proclivity to dismiss the experience of pain in animals.

IMP uses dehumanization as an elucidative tool, in that the de-humanization, and ensuing oppression of other humans is only made possible when the assumption of animals as being lesser, is upheld.

The instance animals are no longer regarded as a subordinate category of species, the devaluing of human outgroups to the level of ‘animal’ or ‘non-human’ loses its impact, entirely.

In summary of what has been previously discussed, it is an individual’s hesitancy to socially identify with animals that acts as a precursor to their ability to liken human out-groups to animals, thereby rationalizing the discrimination, victimization, and denial of rights of these groups.

Fascinatingly, much of what has been discussed within the literature can be summarized by the incongruence present in the two true statements: ‘that humans are indeed animals,’ and ‘that animals are devalued relative to humans.’

Ultimately the cognitive mechanisms that allow for the discrepancy between human identification with other animals and human treatment of other animals alludes to the notion that our thinking about human outgroups and minorities may be implicitly and systematically connected to our thinking about animals, whereby attempting to separate the two psychologically would be a failure to acknowledge their fundamental entrenchment in social domination.


The relevance of the human-to-animal relationship on identity and outgroup prejudice in the human-to-human relationship has only very recently emerged as a subject of interest within academia.

Much of the theoretical framework that relates to the topic holds significant implications for psychology and the adjacent fields of sociology and political science, yet simultaneously falls short of providing comprehensive conclusions.

Many of the mechanisms responsible for identity formation and outgroup prejudice, especially those pertaining to animalistic dehumanization, are unequivocally rooted in the human-to-animal relationship, with an unprecedented array of psychological and sociological benefits resulting from further exploration of these complexities.

The exact extent of the interconnectedness between social dominance orientation, the cognitive mechanisms that underpin phenomena, such as the meat-paradox, Chain of Being, IMP, and the formation of negative bias towards human out-groups, remains to be concluded.

In order for human-to-human prejudice to be fully understood, we must begin to consider our social relationship with animals and the animal kingdom, as the fundamental paradigm upon which all formation of prejudice and outgroup devaluation occur.

Alexandra Walker-Jones — February 2021

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Writer and published author with an international background in psychology, nutrition, and creative writing. I’m just here to learn ;)

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