It’s become somewhat of a well-worn adage that pigs have a similar, or even greater, intelligence than dogs. This is an argument often forwarded by animal advocates as a way to show commonality among species and to try to get the general public to pause and consider that farmed animals may have a level of sentience that precludes them from being consumed. Comparing a farmed animal like a pig to a companion animal like a dog is a strategy that has been employed often, and there is increasing evidence that it is a strong comparison to make. 

In this study, a team of scientists conducted a series of basic experiments to test to what extent companion dogs and pigs defer to their human counterparts in decision-making tasks. To show differences in how each species thinks, the researchers measured the amount of time that each companion animal made or attempted to make eye contact with their human. This was meant to further capture an understanding of how non-human animals use emotions as a cognitive tool to solve problems.

The basic results of the study showed first, that dogs defer to humans to a greater extent than pigs as tasks increase in complexity. While this may reflect the relative intelligence of the two species, it also plausibly shows different adaptive strategies that have emerged through evolution. Additionally, this difference could reflect ways in which dogs and pigs communicate with other members of their respective species. While the primary outcome of interest was the distinction between dogs and pigs, the far more important point for animal welfare advocates is that in communicating with humans at all, both species exhibit profound cognitive capacities.

For the purposes of non-human animal welfare more broadly, this study is but another in the mountain of evidence for extending greater compassion and protection to non-human cohabitants of the planet, beyond the circle of compassion that includes companion animals. To communicate cooperation more clearly allows for an ability to communicate suffering. Certainly, the misery experienced by many captive animals is obvious to the naked eye—perhaps we can become better listeners as well.