IT IS FASCINATING to contemplate that as increasingly social mammals evolved and notions of fairness and equality emerged, a system also evolved to punish the offenders and resolve the conflict. That was the focus of the last chapter: justice. However, justice has come to imply much more than just rules and punishments. In a progressive sense, justice is also about standing up for victims of injustice. It is about righting wrongs, defending the powerless, and refusing to ignore the suffering of others.
What we are talking about here is empathy. Empathy is the capacity to feel for others, usually when they are in pain or have been wronged. It goes beyond understanding what others are going through to actually feeling something for them, as if their emotional condition transfers over to us a little bit. Most people consider this to be a very high-level human emotion. For a long time, we thought that the capacity for empathy and compassion was one of the key endowments that separated us from the animals. We were wrong. There is a long and growing list of animal species in which at least a rudimentary sense of empathy appears to be present.
AWARENESS OF THE SUFFERING OF OTHERS
One of the most striking examples of animals displaying empathy is also one of the oldest. In an experiment that is now more than fifty years old, laboratory rats were trained to press a lever in order to get food. They learned the simple behavior quickly. Then, researchers changed the setup such that when the trained rats pressed the lever, another rat was given a painful thirty-second electric shock in full view of the first rat. The traumatic effect on the observer rats was instant and lasting. After quickly understanding the new framework, they would avoid pressing the lever as much as their hunger would allow. The rate of lever pushes per day went down dramatically. Even after the electric shocks were removed, the rats remained hesitant and pushed the lever far less often than they initially had, an effect that remained for at least ten days.1
This study with rats inspired a similar study with rhesus monkeys. The monkeys were trained to pull on a chain that released food but also gave a shock to another monkey in their group. Because monkey behavior is much easier to visually interpret than that of rats, it was even clearer how upset the monkeys became when they saw another in pain. The monkeys became very resistant to pulling the chain. In a stunning example, one monkey went twelve days without pulling the chain a single time. He pushed himself to the point of starvation rather than hurt his buddy.2
As animal behaviorist Marc Bekoff frequently puts it, these experiments about empathy prove their point so well that it calls into question whether they were ethical to perform in the first place. It is pretty hard not to conclude that the monkeys and rats on both sides of these empathy experiments were in a great deal of discomfort. They were forced to choose between their own need to eat and the well-being of a comrade. In the end, they chose to eat—to live—but they did so with great trepidation. This sounds a whole lot like what humans do in the developed world. You would have to be pretty heartless not to feel guilty sometimes, living our lives of luxury and convenience in a world full of suffering. Ultimately, we still choose to live our lives, and we accept the occasional pangs of guilt that come with it.
In a gentler but even more illuminating experiment with rats, Professor Peggy Mason and colleagues from the University of Chicago found that rats will work to free other rats that are locked in a cage.3 They do this without any reward for themselves and will help both friends and strangers. Interestingly, they are more likely to help rats of the same genetic strain, which is like a breed or race, but cross-strain empathy was also common.
Mason’s group even tempted the rats with chocolate and gave them an either-or choice: free the caged rat or get the chocolate. More than half of the time, the rats elected to pass up the chocolate in order to free a stranger. Perhaps most revealing of all, the rats that chose to let their buddies wallow in captivity while they feasted on chocolate often returned to the caged rat and shared the treat with them. On average, 30 percent of the chocolate that was taken by the free rat was actually eaten by the caged rat. While food sharing is not uncommon among rodents, this almost seems like an apology.
In 2015, scientists from Kwansei Gakuin University in Japan published a follow-up to this work.4 In this scenario, rats were also kept in enclosures and were also subjected to simulated drowning by dousing with water. (Rats have a strong aversion to water and panic when wet.) The scientists found that free rats would again pass up chocolate in order to help liberate their colleagues, and would do so much more quickly when they were in distress than when they were not. This is important because it shows that they were responding to the expressed needs of the other rat, not just the situation itself. Furthermore, rats that had been subjected to the simulated drowning themselves were even quicker to act than naive rats. These rats had “been there,” which appeared to enhance their empathy.
The scientists went further and again employed the chocolate temptation. When rats were faced with the decision to stuff their faces with chocolate or help their apparently drowning buddies, they passed up the chocolate and instead helped their fellow rats more than half of the time. It seems that even rats, considered by many to be among the most vile and unwelcome creatures, experience anxiety, tension, and vicarious suffering in the presence of a fellow rat in pain. To me, this behavior sounds like it is driven by empathy.
Another major discovery in our understanding of empathy in animals was made quite by accident. Dr. Carolyn Zahn-Waxler is a scientist interested in discovering at what point human children become aware of, and show concern for, the emotional states of others. In other words, she studies when humans become able to feel empathy. In one study, her research method was to observe families with young children in their own homes (to eliminate emotional complications caused by having children in an unfamiliar doctor’s office or psychological testing lab). Then, she asked the parents to, among other things, feign sadness by crying and just generally looking and acting despondent. Meanwhile, she observed the children to see if and how they were affected. By doing this, she was able to study the children’s reactions and make important contributions to our knowledge of when and how empathy develops in human children.
Along the way, she also repeatedly observed something unexpected. The young children were not the only ones affected by the visible sadness of the parents. The dogs were, too. Professor Zahn-Waxler observed that, if the family had a pet dog, she frequently responded to the sadness of the parents and displayed a variety of behaviors, including those that could fairly be described as attempts to console.
Like any good scientist, Professor Zahn-Waxler did not just sit on these curious findings. She documented them, explored them further, and reported them to the community.5 Of course, none of us pet lovers are surprised by what she found. We have all had the experience of our dogs or cats knowing when we are down and licking us or just being next to us. And it is not just sadness. Our pets are happy when we are happy and angry when we are angry. Try this at home. In a calm and stoic voice, ask your dog, “Who’s a good boy?” Then, try asking the same question with a lot of energy, a high voice, and a face as bright as sunshine. You will notice a big difference. They are keenly aware of our moods and emotions, and, even further, they care about them.
To be fair, noticing that dogs and, to a lesser extent, cats show empathy toward humans is not quite the same thing as observing empathy among wild animals. These pets have evolved for thousands of years as companion animals, not just domesticated livestock. As a consequence, they experienced very strong selection for behaviors and capabilities that complement us as our steady and loyal escorts. Thus, one could argue that empathy in our pets could be an artifact of their domestication. In other words, it is clear how the ability to empathize would have benefited dogs and cats. What we are really looking for is empathy among wild animals.
Wildlife conservationist CeAnn Lambert witnessed empathy in a wild animal in her own house.6 She found in her garage one morning that two baby field mice were trapped in a utility sink, unable to claw up its slippery walls. They were visibly exhausted and almost certainly suffering from intense thirst and hunger. They could possibly even have been on the brink of starvation, as mice need to eat constantly to maintain their extremely fast metabolisms.
Seeing the mice in this pitiable state, Ms. Lambert decided to help them escape. She gave them some water in a small, upturned plastic lid. However, only one mouse, the larger of the two, availed himself of the water and began to regain some strength and vitality in his movements. The smaller mouse still barely moved, appearing to be at death’s door. What happened next was quite surprising. The larger mouse found a small morsel of food in the sink. Instead of quickly gobbling it himself, he placed it in front of the smaller mouse. The smaller mouse perked up a little bit and started to move toward the nourishing crumb. Then, the bigger mouse moved the crumb a little bit. The smaller mouse kept crawling in pursuit. The large mouse moved the food again, keeping it just out of reach of the smaller mouse.
The late Ms. Lambert was at first shocked by this apparent cruelty but eventually realized that the large mouse was leading the smaller one to the water dish! Once the small mouse reached the water, he took a drink, ate the morsel of food, and slowly began to regain his strength. Ms. Lambert placed a plank of wood in the sink, and the two mice scurried up the ramp to safety.
The take-home lesson here seems to be that mammals from rats to dogs are aware of, and moved to act by, the suffering of their buddies. While we cannot know what they are feeling, their behavior indicates empathy.
Researchers in California led by Hal Markowitz trained Diana monkeys, a species of Old World monkey, to insert a token into a slot in order to obtain food. There was an elderly female in the group that did not quite get the hang of it. She fumbled with the token and was unable to put it in the slot, either because of poor dexterity/coordination or diminished capacity to understand the task. Either way, she clumsily jostled the token while the others ate. A male in the group noticed this, watched her for a few minutes, and then slowly walked over to her, took the token from her, and put it in the slot. He then walked away and allowed her to eat the food that arrived while he watched from a short distance away. This was not just a freak occurrence. The male helped his elderly mate eat on at least three occasions that the handlers were able to witness.7
What else could this have been but compassion? It certainly counts as prosocial or even altruistic behavior. The younger male went out of his way to help and received nothing in return. He saw a companion struggling, and so he helped.
Another heartwarming story of primate empathy comes from our closest relatives, the chimpanzees. At the Center for Great Apes in Florida, there is a chimpanzee troop with a member named Knuckles. Knuckles has the chimpanzee equivalent of cerebral palsy with a host of developmental disabilities. He has severe weakness on his left side and cannot swing or climb; he has a lazy eye and does not appear to see very well. He could not even feed himself for his first few years. He was transferred to his current home when he was two years old.
Ever since being introduced to Knuckles, the other chimps have treated him differently. They are always gentle with him. They do not punish him for spilling things or pushing into them like they would any of the other members. They are tolerant of any disturbance that he causes. Normally, a chimp his age would be subject to the usual chimpanzee dominance displays of pushing, grabbing, screaming, biting, and just general bullying. Nevertheless, the lead handler states that Knuckles has “never received a scratch.”8
Knuckles is not ostracized for being different, either. Other chimpanzees will cuddle with him, hug him, groom him, stroke him, and lead him around by the hand. Even the alpha male of the troop has been seen grooming and caressing him. (There are videos on YouTube of the other chimps playing with Knuckles and caring for him. Go watch them for yourself. Have a tissue handy.)
Why do the chimpanzees do this? If animals are driven purely by competition for survival, how does this behavior fit? It does not. Even if we view this through the lens of social-cooperative behaviors aimed at the good of the whole group, this tolerance and compassion for a disabled member still does not make a whole lot of sense. How would the group be better off by helping a member that can never provide service to the group? Knuckles cannot repay the kindness. He can never take his place in any division of labor, and yet, the other chimps never get angry with him for this. It is difficult to see this compassionate behavior as driven by anything other than feelings of empathy.
Would the chimps show this same compassion to Knuckles in the wild, where the survival conditions are much harsher? I suspect not. The demands on their time and energy would probably be so great that they would simply have to move on and leave Knuckles behind. I do not think there is any reason to believe that they would be deliberately mean to him, but I doubt that they would expend the energy and resources to constantly support him, either. It is a rough life out there in the wild, and Knuckles would probably be too great a burden for the group to bear. (I hope you kept that tissue handy.)
However, lest we be tempted to climb up on our anthropocentric high horses, shall we ask ourselves, “Are humans any better?”
Sure, we do OK now, but until the industrial revolution, when wealth and resources began to reach the huddled masses, human existence was pretty harsh for the vast majority of humans, much as it is for wild animals. How well do you think we cared for the physically handicapped and developmentally disabled during most of our recorded history, not to mention the prehistoric and pre-agricultural period? Imagine how a rugged band of hunter-gatherers suffering through the last ice age in Europe might have dealt with a group member with even a mild physical impairment. Do you think they would be as nice to him as the chimps are to Knuckles? It makes one shudder to think. That is, if one has empathy.
My point is that humans are really no different than the chimps in Knuckles’s troop. We have the same instincts and tendencies toward compassion for our fellow humans, especially those we accept as “one of us.” However, those instincts are tempered by what is feasible and practical given the needs of the group.
Our recent technological, industrial, and economic advancements have allowed us to more generously engage our natural compassion for the less fortunate. We care for each other much better now than we did when life was rough all around. It is the same with the chimpanzees. Out in the wild, the chimps’ compassionate instincts are balanced with the daily struggle to survive. In captivity, however, their temporal needs are met, and they are left with much more idle time. Under these conditions, their natural tendency to be gentle and generous can manifest when faced with the strange and wonderful creature called Knuckles.
Empathy has been studied extensively in chimpanzees, gorillas, capuchin monkeys, rhesus macaques, baboons, Diana monkeys, and a host of other primates. We can now confidently conclude that empathy is a universal feature of primates. Far from being unique to humans, empathy is inherited from our primate ancestors. In all primates, including humans, compassionate behaviors are balanced with selfish behaviors, and the tension between the two is dictated by the overall availability of resources. Chapters ahead will explore this tension in more detail. Further, there is great variability among individuals in a population. This is seen in animals, just as in humans. Some are more predisposed toward empathy and compassion; others are selfish jerks.
COOPERATION BETWEEN SPECIES?
In 2003 in South Africa, a group of antelope was rounded up and captured by a private game-hunting company. The antelope were not to be killed but relocated for a special breeding program. Late one night, the workers were alarmed by the approach of a herd of eleven elephants. The herd circled the enclosure slowly and in a coordinated manner. After the brief inspection, the matriarch explored the gate of the enclosure pen and found the latches. She quickly undid all of the latches and swung open the gate. She signaled to the others in her herd, and they all retreated from the opened gate, so as to leave a free path and not frighten the antelope. The elephants stood back and watched motionlessly as the antelope cautiously approached the open gate and then sprinted through to freedom. The elephants trudged off, slowly disappearing into the night.9
Helping members of your own herd is one thing, but creatures organizing a rescue effort to free animals of a totally different species? That is absurd! Nature is a savage and unforgiving place where only the strong survive! As has been shown in a variety of contexts, sometimes cooperation is even more effective than competition, and many species, especially mammals, have evolved complex cooperation behaviors. Occasionally, those cooperative behaviors pop up even among different species.
Different kinds of animals working together could just be plain ol’ cooperation for mutual benefit. The previous chapter showcased some examples, but there are more. For instance, coyotes and badgers have been known to occasionally hunt together as a team.10 This is a fruitful collaboration because together they can cover the two modes of predator escape employed by burrowing rodents, their common prey. Badgers are diggers, so they can chase prey that burrows; coyotes are pouncers, so they can chase prey that scurries. Because of this complementarity, coyotes are even more successful when hunting with badgers than they are when hunting with other coyotes.
The watchman fish and the pistol shrimp are almost totally dependent on each other. The shrimp deliberately builds a nest big enough for his much bigger fish companion, who then joins the shrimp and sets up camp, and the two work together as a hunting pair. Sometimes, the fish even brings a mate along! The partnership works well: the shrimp has a weapon to immobilize prey and the fish has good eyesight.11
Why would animals of different species help each other? Well, why not? If they are more successful together than they are apart, both individuals benefit. It is as simple as that. But how would these partnerships have started in the first place? It is important to remember that, although some species are in direct competition with one another and others are locked in the struggle of a predator-prey relationship, many more species are simply indifferent to one another. They are in no direct competition whatsoever, so there is nothing to be gained by hostility.
Animals in close proximity often grow accustomed to each other if no threat is present. Over time, trust can build and cooperation is encouraged. I am not talking about the kind of tameness that is seen with wild animals kept in a preserve—when they seem to “know” that they cannot be hunted and are much less skittish around humans. That is just a temporary general comfort level and is not genetic or adaptive. On the other hand, if two non-competing, nonpredator-prey species live together for a long enough period of time, it is conceivable—likely, even—that they will become genetically adapted to recognize each other as nonthreatening. From there, it is not such a big leap that they may learn to work together. If the arrangement is beneficial to both, it will be reinforced. In other words, if reciprocal altruism can benefit members of the same species, why does it not also benefit members of different species?
Cooperation is one thing, but empathy?
There are many anecdotes of cross-species empathy, most of them involving animal empathy toward humans since that is what really gets our attention. In 2009, a beluga whale saved a disoriented diver from drowning at a Chinese zoo in full view of lots of people and cameras.12 There are two cases of zoo gorillas protecting human children who have fallen into their enclosures: Binti Jua, a male at the Brookfield Zoo in Chicago, and Jambo, a female at the Jersey Zoo in England. Both of these gorillas rescued the injured and unconscious human children that fell, gently stroked them, and showed other gestures of consolation and comforting.13 They even aggressively stood down other gorillas that tried to approach. Why would these gorillas and this whale help humans in distress? The only reason that makes any sense is that they felt sympathy and compassion for them.
There was an elephant in India that was a trained construction helper. At one job, her task was to lift large logs with her trunk and put them into holes that had been dug. She performed this task very well with little direction until at one point, she suddenly stopped. She held the log suspended above the hole but would not drop it into place. The human workers came over to investigate the delay and found a sleeping dog in the hole. They woke it up and chased it away. Only then would the thoughtful elephant continue with her task.14
True empathy between different species that is not simply cooperation for mutual benefit does seem paradoxical, even to biologists who accept that animals are capable of empathy. Altruism that is directed toward a different species cannot possibly be self-beneficial and would thus be self-defeating, no?
I do not think there is a paradox here. Evolution can sometimes create sloppy or imprecise products, especially when it comes to something as complicated as behavior. Genes that allow an elephant to feel empathy and share resources with her fellow elephants may also predispose that elephant to feeling generous toward other kinds of animals that she does not feel threatened by. If animals have developed a sensory processing system that is designed to recognize suffering in their own herd, it is reasonable to think that it will sometimes be tripped by suffering in creatures beyond their herd.
Think of humans, for example. Nice people are nice people—usually to everyone and everything. Vegetarianism is more common among the tree-hugging gentle souls among us. Their compassion is just so abundant that it cannot be contained within the confines of their own species but extends to the birds in the sky and the fish in the sea. How often do you meet a genuinely nice person who turns around and beats his dog? When the genes for kindness are expressed in the animal brain, they do not necessarily include the neat instruction of “only to your own species.” If otherwise gentle people are threatened or harmed, it is a different story, but their tendency toward empathy clearly extends beyond just their fellow human beings. Is the same true for other animals?
EMOTIONAL CONTAGION
Human empathy is undoubtedly complex, and scientists have been studying it for many years in all sorts of ways. The human behavior that is most closely related to empathy is the yawn contagion that occurs when one person yawns and another then “catches” the yawn. Yes, you read that correctly. Empathy is similar to yawn contagion. This is because there are neural pathways in common with these two things. Think about it: empathy is the ability to identify with other people’s situations, particularly their pain and suffering. When you see or hear about another’s suffering, your brain constructs those mental images so vividly that you actually cringe and feel some sadness yourself.
For reasons unknown, when you see someone yawn, the neural functioning of this “emotion contagion” is also initiated and your own yawn sequence is activated.15 Your brain identifies with the yawner so precisely that it conjures up an actual yawn.
Empathy is kind of like that. It is as if emotional states are somehow contagious. Have you ever cried at a sad movie? Or recoiled when a boxer got clocked in the face? Or scrunched your face when someone told you about the nasty paper cut that they got? Your outward actions make it seem as though you are actually experiencing the pain yourself, even though you are not. Empathy is emotion contagion; by watching someone in pain or otherwise learning of her situation, you temporarily “catch” the pain yourself, at least outwardly.
The connection between empathy and yawn contagion was first definitively demonstrated in 2003 when researchers noticed that the higher people scored on measures of empathy, the more susceptible they were to yawn contagion.16 This landmark study does not stand alone. Others have validated this phenomenon and probed even further. It turns out that people with schizoid disorders or antisocial personality disorder and those on the autism spectrum all display significantly reduced yawn contagion.17 While those three disorders are all very different in origin and symptomology, they do share one feature: reduced awareness of (or concern for) the emotional states of others. There is no lack of compassion per se, particularly with autistic individuals. Rather, they do not “catch” others’ emotions just by observing them, the same way that they do not “catch” yawns.
It turns out that people tend to “catch” yawns more readily from family and close friends than from strangers or casual acquaintances.18 If we did not know about the connection between empathy and yawning, that would really be a mystery. Everyone knows that we empathize much more strongly with people that we know and love than we do with strangers—and it turns out that we catch yawns from them more easily as well. Furthermore, yawn contagion has been shown to involve similar areas of the brain as perspective empathy (considering things from another’s point of view).
Finally, yawn contagion is present in other animals as well and can even jump across species. Dogs catch yawns from each other; you can catch a yawn from your dog, and vice versa.19 The same goes for chimps and other apes. This yawn contagion is most pronounced in species that—you guessed it—display a pronounced sense of empathy.20 I hope that I have convinced you of the connection between empathy and yawning.
Once again, emotional contagion is at the core of empathy. When you watch someone accidentally smash his finger with a hammer, you typically gasp for air, your shoulders lift, and you may even shake your hand out quickly—almost exactly like you would have if it were your hand that got hurt. But why? If nothing painful actually happened to us, why do we act as if it did?
In the mid-1990s, scientists in Italy discovered something in the brain that they thought held the answer to empathy: mirror neurons.21 Although scientists are still studying the functions of these neurons, they appear to be an important connection between what we observe, what we feel, and what we do. These neurons are activated when you experience something and when you witness someone else experience that same thing. Then, these neurons send their information to various parts of the brain, including those that process complex emotional information.22
The mirror system is somehow involved in the relay of information from our senses to the so-called association areas. Association areas are where we compare sensory input to stored memories so that we can quickly make sense of that input. Once we have matched up what we see or hear with what we already know, we are able to almost experience something through someone else without having to witness it firsthand—that is the power of perspective-taking.
More germane to our discussion of empathy, mirror neurons appear to function somewhere in the bridge between the emotions of others and our own. Imagine you are at work, and suddenly a colleague receives news that her mother has passed away. Your mother is just fine. You never met the mother of your colleague, so you cannot miss her. And yet, you will certainly be moved to sadness. You may even tear up and cry with your colleague. Empathy does not pertain only to pain and sadness; it works for happy things, too. We cheer along when the protagonist of a movie succeeds; we feel genuinely happy when a janitor wins the lottery. If the mirror system is the connection between seeing others in a certain emotional state and our catching that emotional state ourselves, it could be the physical basis of empathy.23
What is the evidence that mirror neurons are involved in empathy? First, if mirror neurons are the key operators in human empathy, we would expect to observe some sort of malfunction in the activity of mirror neurons in individuals with autism since we know that many autistic people do not empathize as readily. Sure enough, scientists have now pinpointed some of the functional differences in people with autism, and—you guessed it—mirror neurons seem to be different.24 Similarly, remember how contagious yawning correlates with empathy in humans and other species? Once again, the underlying connection is the action of mirror neurons.25
More recently, some scientists have begun to question the centrality of mirror neurons in empathy and emotional awareness. Some scientists believe that they are merely reflective of an underlying empathy system, not the engine of it. (Please pardon the pun.) While everyone agrees that the mirror neuron system is a huge discovery, many scientists are beginning to doubt that these neurons will live up to the initial hype. For our discussion here, it does not really matter if mirror neurons are, themselves, the instruments of empathy or if they are only a part of it. They could even be casual bystanders, for all intents and purposes. The point here is that we have discovered a way to measure at least part of the neurological functioning that occurs during empathy, perspective-taking, and contagious yawning. The cloud of mystery is beginning to lift. We are getting tantalizingly close to a cellular understanding of the complex emotional quale known as empathy.
If that seems farfetched, now may be a good time to remember that we are wise not to underestimate science. Just one hundred years ago, no one had any clue how sound and hearing worked, and now we have such an incredibly detailed understanding that we can surgically implant electronic devices that replace much of the machinery of hearing and send the neural-aural information directly to the brain. Biologists are now dissecting empathy with that same resolve. They have found a neural system that helps us understand what others are feeling by “mirroring” these feelings in our own brains. With that in mind, the connections between empathy, yawning, and autism are not so mysterious. If our progress in the understanding of empathy proceeds as successfully as it did with our understanding of sound, I wonder if someone will one day invent the empathy equivalent of the cochlear implant. Will we one day be able to treat people born without empathy?
It turns out that not only do other animals have mirror neurons, but we also actually understand more about animal mirror neurons than we do about human ones. The reason is that, right or wrong, the regulatory boundaries of what is considered ethically permissible are different for humans than for animals. With animals, scientists can engage in far more invasive experimentation that would be too risky or harmful to perform on humans.
In fact, mirror neurons were first discovered in rhesus macaques in the early 1990s and only later pinpointed in humans. As noted earlier in this chapter, animal empathy was first “discovered” in rhesus macaques back in the 1960s when the monkeys refused to pull a chain for food if their friend would be shocked. I find it to be a very satisfying coincidence that the same monkey species was the subject of two totally different groundbreaking experiments, decades apart, that would end up converging around the conclusion that animals exhibit empathy.
Mirror neurons have now been discovered in whales, dolphins, mice, rats, birds, all kinds of monkeys, and many other animals. Their existence seems to be widespread in the animal world, and there is an overall correlation between intelligence/cognitive ability and the prevalence and size of these mirror systems. Whether used for empathy and emotional connection or just for understanding the simple physical actions of others, there is a system in place in “higher” animals that facilitates their ability to understand the perspective of another being. This appears to be the root of empathy and compassion, and animals certainly have it.
Given that humans have more extensive cognitive abilities and more complex emotions, our mirror system would have to be quite a bit more sophisticated to keep up with all of this. Experiments have borne this out. It turns out that, in humans, our mirror neurons are not easily fooled. For example, some of the same neural circuitry is activated when you watch someone pour a glass of water as when you pour the water yourself. However, if you know for sure that the pitcher has no water in it, and the person is just faking the action of pouring water into a glass, the mirror neuron circuitry is not activated in the same way. The “mirroring” of water-pouring in your brain does not occur.26
This shows substantial sophistication. Most animals are easily fooled by pantomime, but humans require an elaborate ruse in order to be duped. There are two possibilities here. Either our mirror system developed complexity and intelligence hand-in-hand with our cerebral cortex, or our mirror neurons receive the information from the cerebral cortex after it has been extensively processed. Neuroscientists will surely be able to answer that question soon, but in the meantime, it does not matter for our discussion here. Human brains display much more sophistication in perspective-taking than animal brains do, and this may help explain the much more complex version of empathy in humans.
THE EVOLUTION OF EMPATHY
Now that there is convincing evidence that animals experience empathy, the questions emerge about how and why it evolved in the first place. What is the advantage to an individual to feel the pain of another? What is to be gained? The best way to understand how and why an emotion has evolved is to consider it as an internal drive to engage in some behavior. To find out why empathy evolved, we must first ask, “What does empathy drive us to do?” That will help answer our question.
Think about hunger. Hunger, in itself, is pointless; it is simply a form of discomfort. The power of hunger is that it drives us to do something: to eat. Empathy, then, is clearly a drive to help others. The feeling of pain that we experience when we see others in pain is like an internal push to help that person. It is an internal feeling of discomfort that drives us to help an injured or otherwise needy colleague. Empathy leads to compassion, which is the act of actually wanting or intending to do something to help.
In its earliest forms, perspective-taking likely emerged as a brain function for understanding the actions of others. In the simplest animals like sponges, coral, and jellyfish, the neural system is nothing more than simple input-output reflexes. There is very little processing of the inputs. However, over hundreds of millions of years, species evolved increasingly more complex neural systems. Rather than activating a simple output function, the sensory input began to be processed so that more nuanced and sophisticated outputs would result. In other words, animals with more sophisticated brains gained the ability to take in various sensory inputs, integrate them with other inputs stored previously, and build an understanding of the world around them. The neurons that are neither sensory nor motor, but instead are involved in integration and processing, are called interneurons, and the human brain is filled with them.
The number and interconnectedness of interneurons increased to staggering levels over the course of evolution. Leeches, slugs, and snails have ten thousand to twenty thousand neurons in their entire bodies, while whales and elephants have about ten billion just in their cerebral cortex, the part of the brain in which higher cognitive functioning occurs. We humans have more than twenty billion neurons in our cerebral cortex. And that is just the number of neurons. The real measure of complexity is in the number of connections between neurons. Neuroscientists estimate that humans have at least ten trillion connections, and it could be much more. By far, most of these are connections between interneurons and are responsible not for simple sensory or motor functions but for advanced processing.
As animals became better and better at understanding all of the sensory information around them, their brains developed tricks to do so more efficiently. Animal brains have the ability to “fill in the blanks” when there is only partial information. We do this by comparing incomplete sensory information with information that we have already stored as memories. It is all very automatic and occurs instantly in association areas. Imagine you are looking through a dark, crowded theater for someone that you know. Way off in the distance, you might see the back of her head, and that is all you need to identify her. Your brain fills in the rest. The whole world of optical illusions and stage magic is built on the premise that our brains will fill in the missing pieces of an incomplete picture.
How does this relate to empathy? These association areas in our brain are where sensory input is compared with what we have already seen, felt, heard, or experienced. When this happens, it conjures up those experiences in our head as though we are really experiencing them. Try this. Close your eyes and picture the face of your best friend (or father, sibling, or spouse, if you prefer). You can actually conjure up a pretty vivid image of that person in your mind. Your eyes are not taking in any sensory information about her, and yet, the visual centers of your brain are registering her likeness. This process can be observed in a brain scan. The primary visual cortex of your brain lights up when you imagine things, almost as if you are seeing them live.
In regard to empathy, your brain is wired to conjure up stored sensory imagery on command. Perspective-taking, which is the action of “putting yourself in someone else’s shoes,” can involve assuming someone’s literal perspective, or it can involve taking their emotional perspective. Animal brains can do both. Initially, this was surely rudimentary, nothing more than interpreting the physical behavior of others through sight and sound. You would be a more successful lizard if you were able to interpret the behavior of other lizards. If you could figure out when they were seeking or receptive to mating, you’d have an advantage. If you could figure out when they were angry or threatened, that would help, too. If you understood when they wanted to play, kudos. And so on.
Empathy is the act of receiving communication, specifically emotional communication. In fact, when mirror neurons were first discovered, some scientists immediately believed they were the key to communication and language. That belief has waned, but some role for the mirror system in language and communication seems likely. This notion is edified by the fact that the most severe cases of autism involve a complete lack of language ability.27 Regardless, there is both a conceptual and a neurological connection between emotional contagion and basic body language and signals. The genesis of empathy was the ability of animals to understand and interact with one another.
In this light, it does not take an evolutionary biologist to figure out the value of full-fledged empathy. Imagine a pack of wolves in the wild. If one member is hungry or injured and another member notices this and is moved to help him, he might just save his life. Couple this with a little reciprocity (see chapter 2), and you have a recipe for cooperation. In a social species living in tightly knit communities, members helping one another is almost always good for the survival and success of the individuals and the group. Evolution would favor this trait.
Of course, empathy, as an internal urge to do something, is always tempered and balanced against other urges. For example, if a zebra sees his friend being taken down by a lioness, he may very well feel a strong urge to help him. This urge, however, will be overwhelmed by other urges, namely the urge to save himself by fleeing. A chimpanzee may be moved to help a hungry pal, but if she is hungry herself and has only a little to eat, she probably will not help. All animals are being bombarded by senses, urges, and drives, and depending on the relative strength of each one, different outcomes are possible.
The same is true for humans. We see and hear about fellow humans in need all the time. Of course, most of us feel empathy for the less fortunate, and we really want to help, but few of us will take all that we have and give it to the poor. Our own empathy is balanced with our other drives and desires. In addition, empathy is much stronger toward those we identify as “one of us.” We have all seen fundraising pitches from friends regarding some friend of theirs that has breast cancer. I bet you are much more likely to donate money when it is your own friend that is sick, rather than a friend of a friend. Do we think the stranger is unworthy of our help? Of course not. It just hits much closer to home when the subject is someone we know. This is how empathy works.
The subject of empathy often raises a very uncomfortable issue: there are people that seem to lack empathy altogether.28 Previously referred to as sociopaths, individuals with antisocial personality disorder, or in the extreme, psychopaths, present a difficult problem for psychologists and public safety. For our discussion of animals, this begs the question: are there psychopaths in nonhuman animals? Professor Lori Marino and her students at Emory University asked that precise question and, in the process, developed a behavioral scoring system for the detection of psychopathy in chimpanzees.29
Yes, just as in humans, empathy is not distributed equally among chimpanzees. Some are thoughtful and some are jerks. Even more interestingly for our discussion is how similar the detection of psychopathology is in chimpanzees and humans. The Chimpanzee Psychopathy Measure developed by Marino bears striking resemblance to the way that psychologists detect psychopathy in humans. The presence of empathy in chimpanzees is made even more obvious by its absence in some members.
THE FOUNDATIONS OF MORALITY
In what little documentation we have of early human history, it seems the establishment of moral and legal codes was a ubiquitous feature of civilization, and necessarily so. If fairness is important for communities of hundreds of mammals, it will be absolutely essential for cities with thousands of human mammals. But is there a difference between enforcing equity and establishing morality? This will depend on your definition of morality and, for many, will be intensely tinged by religion. Despite the many differences among the world’s religions, there is a moral common denominator: do unto others as you would have them do unto you. Christians know this as the Golden Rule, but versions of it appear in nearly all world religions and long predate Christianity.
In a purely practical sense, morality is the union of empathy and fairness. However, these two phenomena may actually be the products of the same evolutionary force—the socialization of our mammal ancestors. As Professor Frans de Waal puts it, “The two pillars of morality are reciprocity [or fairness] and empathy [or compassion].”30 I think most of us would agree with this statement, and it certainly fits the moral framework of the world’s major religions and philosophical schools of thought. (By the way, Frans de Waal is not a philosopher or a cleric. He’s a member of the U.S. National Academy of Sciences who has spent his life studying the behavior of primates.)
All major religious texts contain obvious plagiarisms of writings that came before them. Despite that, all religions claim credit for giving us the code of morality. A simple look at how animals behave discredits this claim. The truth is that animals behaved according to the two pillars of morality for hundreds of millions of years before humans evolved to a state when they could arrogantly claim authorship of rather basic social-cooperative precepts as the Golden Rule. What we now consider the human moral code was written into the genes of our ancestors eons before the first prophet or shaman took credit for it. Although recent research has given us dramatic support for this hypothesis, it is not a new one. Charles Darwin himself noted it more than a century and a half ago: “Any animal [whatsoever], endowed with well-marked social instincts…would inevitably acquire a moral sense of conscience, as soon as its intellectual powers had become as well, or nearly as well developed, as in man.”31
The study of the morality of animals is picking up steam in the field of biology.32 Ethology is the field of biology that specifically studies the evolution of animal behavior. Within this field, there are many scientists that have come to the conclusion that some species of animals often behave according to a set of norms and tendencies that mirror the moral sense of most humans. They may not actively think about morality, but they behave as if they do. I find this intriguing because it is as if moral behaviors evolved before the ability to think about our behavior in moral terms.
I offer a parallel. We have an elaborate nervous system in our gut called the enteric nervous system. It not only choreographs the elaborate muscle movements that usher food through the various intestinal compartments, but it also senses the amount and composition of our stomach contents in real time. It can respond with precise combinations of a dizzying palate of secretions and hormones. The actions of all the glands and muscles in our abdomen are carefully orchestrated and responsive to the conditions from moment to moment. And yet, we have absolutely no awareness that any of this is going on. We have only the vaguest sensations of fullness and emptiness—and occasional queasiness. The rest is completely unconscious and involuntary.
My point here is that a lack of full awareness of some neural function is not evidence against the existence of that function. This could apply to the question of animal morality. Even if animals have no conscious awareness of their own moral instincts (and good luck proving that they do not), that is not evidence against their having one. Instead, the evidence that they do or do not have some moral instincts comes from studies of their behavior. Do animals behave as if they are operating on the basic pillars of morality? At this point, I think there is far too much evidence to deny that they do. This chapter and chapter 2 are filled with examples that are resonant and telling, but there are many more out there, both in the scientific literature and the popular press.
Allchin, D. “The Evolution of Morality.” Evolution: Education and Outreach 2 (2009): 590–601.
Bekoff, Marc. “Are You Feeling What I’m Feeling?” New Scientist 194 (2007): 42–47.
De Waal, Frans B. Primates and Philosophers: How Morality Evolved. Princeton, N.J.: Princeton University Press, 2009.