Although dogs and pigs share many similarities, including behaviors, emotions, appearances, and levels of intelligence, people in Western cultures typically favor dogs over pigs. Dogs are viewed as companion animals, while pigs are often seen as food animals. This bias, called “pet speciesism,” has moral, legal, and environmental consequences. Viewing “food animals” as lesser than “pet animals” leads to attributing lower moral statuses, lower empathy for the animals’ harm, reduced animal welfare laws, and greater meat consumption of the non-pet species. 

In this study, researchers aimed to identify the variables contributing to pet speciesism, particularly why people in Western cultures have a more favorable perception of dogs compared to pigs. A sample of 232 volunteers participated in the online study. The majority of participants were meat eaters, female, lived in the U.K. or U.S., and were white. Volunteers rated 12 different statements in order to find any significant relationships between different factors and pet speciesism.

The authors used the stereotype content model as a framework to understand the differences in perceptions between dogs and pigs. This model categorizes social perceptions based on warmth (i.e. having positive behaviors) and competence (i.e. having the capacity to perform those positive behaviors). The study found that dogs are perceived as warmer, more competent, less as “profit animals,” and more as pets — largely due to their perceived familiarity and similarity to humans. In general, greater empathy with animals increased perceptions of warmth and competence for both dogs and pigs, with a stronger effect for dogs.

The study suggests there are many variables that predict pet speciesism for both dogs and pigs. These include familiarity, similarity, pet status, empathy toward animals, and their meat consumption habits and desires. However, the research did not show that approval of using animals for human benefit (also called “animal utility”) explained pet speciesism. These findings therefore emphasize how enhancing the positive behaviors (and their capabilities to perform them) of animals can improve perceptions towards them.

The research had a number of important limitations. The study ignored the characteristics inherent to dogs and pigs. For example, dogs have humanized facial expressions, and can respond in ways similar to human infants. The study focused mainly on British and U.S. cultures, and relied on self-reports, which can lead to participants misrepresenting their views, such as underreporting their meat consumption.

This study suggests that if the aim is to encourage more positive human behaviors towards pigs, people may need to perceive pigs as being warmer and more competent than they typically do. Interacting more with pigs and highlighting their similarities with humans can foster greater empathy and concern for pig welfare. The researchers suggest that the impact of such changes in perceptions could be that people will care more about pig welfare, reduce their pig meat consumption, and even put greater pressure on organizations that use pigs as food. Therefore, efforts for animal advocates to improve the perceptions of animals can have a direct influence on how people treat those animals.