After boorish behavior, pigs kiss and make up
Hogs join humans and apes as one of the few animals that console their companions after fights
Hell is other people — at least according to the philosopher Jean-Paul Sartre. If Sartre was a pig, though, he might be inclined to say that heaven is other hogs.
When left to their own devices, pigs form tight-knit herds called sounders, made up of adult females and their offspring. Sows babysit piglets that aren’t their own, even suckle them, and at night they all sleep in a communal nest made of grass and branches. Just like humans, when one sleepy pig yawns, the others will too.
Of course, conflict happens, even in the most utopian of societies. As a new Italian study has found, pigs have mastered a skill that seems to stymy many humans: making amends after a fight.
The hundred-plus pigs of Parva Domus, a free-range farm in Turin, Italy, don’t have much to bicker about. They’ve got plenty of food, and 120 acres of meadow and woodland to roam. Anthropologist Giana Cordoni, of the University of Torino, was curious what happens when conflicts do crop up. She knew from her past research that for other social species — gorillas, wolves, and wallabies — “kiss and make up” is a crucial part of group living.
As she and her colleagues would discover, pigs are no different. After an altercation, both culprit and victim will bump noses, or sit or lay in physical contact. Once apologies have been oinked, signs of stress decrease — actions such as yawning, scratching and chewing. The most remarkable finding, Cordoni says, is that bystander hogs often approach the combatants afterwards to comfort them. Until now, this sort of third-party consolation has only been observed in humans and higher primates. “In our opinion, this is very extraordinary,” she says.
Grad students did the grunt work in the study, following the herd around the sprawling farm and videotaping the pigs’ interactions. They did this every day for five months, from 7:30 AM to 5 PM. When asked if there were any stand-out episodes from this effort, Cordoni calls across the office to one of her students. The answer? Not in particular. “Hard work,” Cordoni admits. “But then research is hard work!”
For Melissa Shyan-Norwalt, an animal behaviorist at the University of Cincinnati who was not involved in the study, this hard work was worth it. “I thought it was a great study,” she says, adding that the design and interpretation of results were sound. She was particularly interested in one finding: that after an aggressive bite or push, immediate family members usually fail to make amends. Pigs recognize their mothers and siblings, and can remember them even after long periods of separation. Given how vital these connections are in swine society, why would a pig choose not to say sorry to mom?
The key, Shyan-Norwalt says, is something called the uncertainty reduction hypothesis. Pigs know that their bonds with immediate relatives are unbreakable. Like humans, they can afford to take family for granted. But with non-relatives, unresolved conflict feels uncomfortable, even scary. Not knowing whether the next interaction will be a bite or a nuzzle is stressful. And eventually, accumulated grudges can cause a group to fall apart, exposing members to predators and hostile outsiders.
That’s why reconciliation is so vital — it shows each animal that the threat has passed, and that their social circle remains intact. It’s exactly what Shyan-Norwalt found in her study of dogs in a dog park. “The ones that usually got into conflicts were ones that did not know each other,” she says. The pups reconciled to reduce “the uncertainty of whether or not another fight was going to occur.”
Most hogs raised for meat don’t get the opportunity to practice their considerable social skills. An estimated 97% of pigs in the United States spend their lives on slatted floors in dim sheds, without any way to express natural behaviors such as rooting, nesting and socializing. Breeding sows are often confined to crates so small that they can’t turn around. The animal welfare advocate Temple Grandin has compared this to a person spending their lives in an airplane seat.
Cordoni acknowledges that while large commercial pig farms are important for getting pork on the table, we can’t neglect the hogs’ needs while we’re raising them. “They are fantastic animals,” she says. But does she think any differently when faced with a plate of prosciutto? Cordoni laughs and replies that humans are omnivorous by nature. “I have to behave like my nature,” she says. “I eat salami, but with respect.”
