Pigs show potential for a “remarkable” level of mental and behavioral flexibility in a new study

Pigs will probably never be able to fly, but new research reveals that some species in the genus Sus may have a remarkable level of mental and behavioral flexibility. A study published in Frontiers in psychology tested the ability of four pigs to play a simple joystick-enabled video game. Each animal demonstrated some conceptual understanding despite the limited skill in tasks normally given to nonhuman primates to analyze intelligence.

The study included two Yorkshire pigs named Hamlet and Trout, and two micro pigs Panepinto, Ebony and Ivory. The four animals were trained to approach and manipulate a joystick with their snouts in front of a computer monitor during the first phase of the experiment. They were then taught to play a video game in which the goal was to move a cursor with the joystick toward up to four target walls of the screen.

Each pig performed the tasks well above chance, indicating that the animal understood that the joystick movement was connected to the cursor on the computer screen. According to the researchers, the fact that these very long-sighted animals with no opposable thumbs can be successful in the task is “remarkable.”

“It’s not uncommon for an animal to understand the concept that the behavior it performs has effects elsewhere. That pigs can do it in any degree should pause us on what else they are able to learn and how this learning can affect them, ”said lead author Candace Croney, a professor at Purdue University and director of the Purdue Center for Animal Welfare Science. Sarah T. Boysen, known for her work on the cognition of chimpanzees, co-authored the study.

Scientists already know that pigs are able to learn various types, from the same type of basic obedience commands that are taught to dogs as “coming” and “sitting” to more complex behaviors that force them to change. of behavior when the rules of the game change. A study has even shown that pigs can use mirrors to find food hidden in an enclosure, Croney noted.

In the current study, the team used food to teach and reinforce behaviors, but also found that social contact could strongly influence its persistence. For example, when the candy dispensing machine did not work, the pigs continued to give correct answers using only verbal and tactile cues. And only verbal encouragement seemed to help the animals during the most difficult tasks.

“This kind of study is important because, as with any sentient being, our interaction with pigs and what we do to them impacts and matters to them,” Croney said. “Therefore, we have an ethical obligation to understand how pigs acquire information and what they are able to learn and remember, as it ultimately has implications for how they perceive their interactions with us and their environments.”

Although pigs could not match the skill level of nonhuman primates in the video task and did not meet the criteria used for primates to demonstrate complete mastery of the concept, the researchers said the shortcomings were they could be explained in part by the nature of the experiment, designed for dexterous and visually oriented mammals.

The study ended before researchers could investigate a more ambitious goal: whether a computer interface as well as symbols could be used to communicate with pigs more directly, as has been done with nonhuman primates. .

“Reporting on management practices and improving pig welfare was and still is an important goal, but really this is secondary to better appreciating the uniqueness of pigs out of any benefit we can derive from them,” Croney said.

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