A Sentience Article from All-Creatures.org

Pig Intelligence

From Meghan Jones, Factory Farming Awareness Coalition
September 2022

By challenging harmful stereotypes and our commodification of these social, creative beings, we can begin to look toward a brighter future that treats animals of all species with more respect, regardless of their intellectual capacities.

Many of us who live in the United States haven’t had the opportunity to meet a pig, other than in the form of a food ingredient on our plates. While we form intimate, bonded relationships with cats, dogs, and other companion animals, we often fail to recognize that animals raised for food display many of those same loveable traits as our furry best friends. Pigs, like the cats and dogs we share our homes with, are very intelligent, communicative, and emotional beings, so it begs the question: why eat one and love the other?

Are Pigs Intelligent?

Decades of research on pigs has found that pigs are highly intelligent beings. In clinical trials, they have been shown to have abstract thoughts, use tools, recognize their own names, dream, and follow commands. Other tests have revealed that pigs can play video games and even differentiate between drawings they made over other pigs’ artwork!

Interestingly, we share about 98% of our DNA with pigs, compared to only 90% in cats and 82% in dogs. This makes us about as closely related to pigs as to chimpanzees, who also share 98% of our DNA. This similarity in DNA explains why pigs are often used as human surrogates in the medical industry—whether as models in medical and scientific research, or for use in medical training programs, due to their anatomical similarities to humans.

Do Pigs Have Emotions?

Anyone who has spent time around a pig knows that they are able to communicate their feelings fairly clearly. We know they are happy when they ask for belly rubs by flopping over at your feet, we know they are in distress when they squeal and show aversion to a subject. Multiple studies confirm that pigs are able to feel and express many of the same emotions that humans do, such as happiness, anxiety, stress, joy, fear, and anger. They can form complex relationships and bonds with other pigs, often developing friendships that can last a lifetime, and showing signs of grief when close friends or family members die. Pigs are highly social animals, but that doesn’t mean they all get along equally. In fact, introducing new pigs to a sounder, or group of pigs, often results in fights, not only because pigs can differentiate other pigs from one another, but because they also form complex interpersonal relationships and can be wary of new pigs who may disrupt these pre existing hierarchies.

How Intelligent Are Pigs?

Are Pigs More Intelligent Than Dogs?

Research shows that pigs are at least as intelligent as dogs, and in many cases even outperform dogs on tests of cognition, memory, and other measures of intelligence. For example, not only can pigs be taught how to fetch like dogs, they can also differentiate between objects, for example a ball vs. a frisbee. In fact, when it comes to problem-solving, pigs far outperform dogs.

Pigs are also similar to dogs in that they love to be around humans, and will often turn to humans first for emotional support.

How smart are pigs in human years?

Pigs have been found to outperform three-year-old human children on tests that measure cognitive skills. At three years old, a human child is focused on learning and exploring, enjoys playing, and shows self-awareness. This is also the case for pigs which demonstrate distinct likes and dislikes, enjoy playing creatively, and display a range of emotions similar to those of a child. Due to these shared capacities, pigs have been compared cognitively to three-year old humans when it comes to measuring intelligence based on human standards.

Why do we love one and eat the other?

Talk with anyone who has interacted with pigs at a farmed animal sanctuary, and you’re sure to hear tales of escape artists, charmers, belly-rub enthusiasts, and pigs with serious sass. They’ll be sure to mention their big personalities and vast intelligence and problem-solving abilities that pigs have. In the developed world, however, the vast majority of these intelligent, feeling individuals spend their entire lives intensely confined in factory farms. Why is this so, especially now that we know that pigs share many of the same loveable traits that cats and dogs do?

The species that we choose to eat are based on our complex social and cultural histories with different animals, and the lines between animals considered “food” vs. “friends” are arbitrary. The invisible forces of the societies we grow up in have conditioned us to believe that some animals are “food” while others are “friends.” This societal normalization of consuming some animals but not others is referred to by Dr. Melanie Joy as “Carnism.” We can see these social forces at play very clearly when we put different cultures in conversation with one another. Consider that different cultures draw very different lines when it comes to which animals are included in the “edible” category, especially juxtaposed with those species who may be considered “friends” by another culture. For example, people in the U.S. typically consume cows, while in many parts of India, cows are viewed as sacred beings and are even afforded legal protection under some jurisdictions’ laws. Guinea pigs are often considered “pets” in the U.S., but are consumed by some indigenous Peruvians, and have more recently become regarded as a delicacy.

What makes pigs smart?

Cognition

Animals exhibit cognition if they have the ability to learn from their past experiences, think through problems, and make informed decisions about their future. Studies that have sought to measure pigs’ cognitive abilities have revealed that they understand the passage of time, can distinguish between various objects, and use memory and the knowledge of past experience to inform their decisions. They have a concept of both the future and the past, and show self-awareness.

Communication

Pigs are highly communicative, and if you have ever met a pig you have likely discovered this very quickly. In studies that look at pig grunts, it was found that not only do pigs communicate in a variety of “tones” to signify different situations and emotions to one another, they also may be more or less “talkative” based on their personality. Pigs use acoustic signals in a variety of contexts, for example in maintaining contact with other group members while foraging, in parent–offspring communication, and when they are distressed. In some cases, it has even been found that mother pigs will “sing” to their young much like some human mothers do.

Memory

It has been proven that pigs have memory skills similar to our own, meaning that they can easily keep track of everything that happens around them for a long period of time after it happened. Pigs are able to discriminate between objects, and tend to prefer new, novel objects to those that are familiar to them. Studies that looked at pigs’ ability to remember situations have found that not only can they remember experiences, but they can also prioritize important information from memory. For example, in one study, they were able to remember which food site had more food, and used memories of food odors and color cues to navigate, using spatial features for reference, to the preferred site.

Their memories also allow them to have a concept of time, with one study showing that when given an option between crates with differing length of confinement, pigs remember which crates would result in their being confined for longer, and preferred crates that resulted in a shorter period of confinement.

Pigs are Empathetic

Pigs possess what is called emotional contagion, or the expression of an emotion after seeing that emotion expressed in others. This ability is thought to be the basis of empathy, as it demonstrates that someone can recognize emotions in others, and be affected by that emotion.

While it can be challenging to study and interpret emotions, especially in other species, the emotional experiences of pigs can be clearly seen in their play, fear and stress responses, and their sensitivity to the emotions of their companions.

Pigs are one of the cleanest animals

Despite the stereotype of pigs being dirty, covered in mud, or living in “pig styes,” pigs are actually considered to be the cleanest of all farmed animals. Pigs can smell odors as far as 5-7 miles away, and about 25 feet under the ground, and their keen sense of smell may be one reason why when given enough space, they keep their sleeping and eating areas meticulously clean. Some pigs have even been known to decorate their living areas with flowers and other found items.

Pigs are Very social

Multiple studies have shown that pigs not only have distinct personalities, but also that they form strong bonds with others. One only has to spend a short amount of time with pigs to realize that they are unique individuals with differing temperaments, personalities, and social groups! Maternal bonds are particularly strong, with many mothers preferring to stay with their young even after their young are grown. Pigs will often sleep in the same space as their families or friends, and can form lifelong bonds with other pigs. Pigs also form social hierarchies, and introducing a new pig to an existing group will often lead to fights as the new hierarchies and orders of dominance are established.

Problem-Solving Skills

Pigs have been found to be able to problem-solve better than most other animals, and are highly capable of solving problems independently. While dogs, when presented with a problem, will turn to humans for assistance, pigs will ignore humans in lieu of figuring out the problem on their own. They might even use tools or memory to assist them in their problem solving.

They Feel Pain and Suffer

As pain is a subjective, personal experience, attempts to objectively measure it scientifically in animals other than humans are particularly challenging. That being said, there are a few cues we can look for, including vocalizations, escape or avoidance behavior, and anatomical similarities to humans. In studies of the effect of various agricultural practices on pigs, it was found that many of the standard practices used in the pork industry cause acute pain, and researchers concluded that pain management (in the form of different techniques or providing pain relief such as anesthesia) should be a requirement. Examples of painful procedures include castration, tail docking, and removal of teeth (all performed without anesthesia for pain relief), all of which are standard practices in the pork industry. Injuries and disease are also common sources of pain for pigs in the pork industry.

A study from Brazil that interviewed 44 pig farmers also found that all 44 believed their pigs could feel pain and suffer.

Tool use

Studies have found that pigs, like many other vertebrates, have the ability to use tools. Tool-use is commonly seen as a sign of higher intelligence in nonhuman animals. From using bark to dig, to understanding how video games work by moving joysticks and seeing the effects on a screen, pigs have demonstrated their ability to problem solve and accomplish tasks through the use of various objects.

Pig Intelligence Facts

Pigs:

• have excellent long-term memories
• understand symbolic language
• have a sense of time, remember specific episodes in their past, and anticipate future events
• are excellent at navigating mazes and other spatial tasks
• play creatively
• live in complex social communities and easily distinguish other individuals, both pigs and humans
• have an understanding of others’ perspectives as shown in their ability to use tactical deception
• are emotional and exhibit empathy
• show a form of self-recognition and self-agency in their abilities to manipulate joysticks and use mirrors to find food
• have distinct personalities
• can dream
• are strong swimmers
• can use mirrors to find hidden objects
• sing to their young

Does Intelligence Matter?

Even if pigs didn’t possess such impressive cognitive abilities, we would still need to ask ourselves if the lack of certain types of intelligence justifies the horrific treatment and fate as food products that we subject them to. Consider the example of human toddlers, whose intellectual abilities fall below that of many other animal species, including pigs in many cases. Should we discriminate against them because of their intellectual abilities alone, or are there more meaningful measures to use instead to determine their treatment? The renowned philosopher Jeremy Bentham suggested that suffering might be a more appropriate measure to consider when thinking about how we treat other beings, reasoning “The question is not, Can they reason?, nor Can they talk? but, Can they suffer?”

It’s also important to keep in mind that there are many forms of intelligence, and comparing intelligence across species is not only incredibly difficult, but can also be problematic in multiple ways. For example, consider the many species of birds who can navigate thousands of miles every year to find a specific tree or nesting ground by using a variety of different cues, including the earth’s magnetic fields. Cows develop friendships and can identify and navigate to sources of water in their environment. Many types of fish communicate in complex ways using their fins, subtle movements, and low-frequency sounds that humans are unable to hear. All of these abilities perhaps supersede human capabilities, yet are not often thought of as signs of intelligence due to our using human intelligence as the bar to which we compare all other animals.

Conclusion

While we often think of pigs as being dirty, lazy, or unintelligent, these stereotypes couldn’t be further from the truth. Pigs are social, unique, resourceful, and voracious animals, with the ability to feel pain, empathize with one another, form lifelong friendships, experience joy, and in most cases, love a good belly scratch. Knowing what we now know about pigs, it is important to consider how our categorization of pigs as commodities impacts their treatment in factory farms, use in the medical and scientific communities, and dismissal as simply ingredients on our plates. By challenging these harmful stereotypes and our commodification of these social, creative beings, we can begin to look toward a brighter future that treats animals of all species with more respect, regardless of their intellectual capacities. After all, every species has unique capabilities that are worth celebrating!

Sharing this article helps raise awareness about the impact of factory farming on humans, animals, and the environment.

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