'I am very curious, how can scientists possibly know whether or not humans in the past (thousands upon thousands of years of evolution) had empathy? How do we know which ones had empathy and which ones didn't? How do we know that it was the ones who had empathy that survived better?'
Why wouldn't they have had? Since it was present in some lower animals, it would have been present in humans who sprang from them.
Here is an excerpt from the new york times which discusses empathy as the foundation for morality:
One day the female was attempting to get at a tire hanging from a pole, because the tire held a reservoir of water and she was thirsty. However, there were other tires in the way of the water-filled one, and as much as she struggled to push them aside she could not get to her desired object.
After half an hour of failures, she walked away dejectedly, at which point the male, who had been watching her efforts the entire time, set to work. He pulled down the intervening tires one by one until he reached the rubber grail. Lifting the tire from the pole, he took it to the female, left it with her to drink from, and knuckle-walked away. "That whole thing tells you the chimp could put himself into her position and see what kind of problem she was trying to solve, a problem that he knew how to solve," said Dr. de Waal.
Beyond animal compassion, researchers are considering empathy's role as the foundation of human morality, its usefulness in encouraging cooperation among strangers or provoking guilt in wrongdoers. At the same time, researchers acknowledge that even a generally desirable state like empathy can have its ugly consequences. Dr. Martin L. Hoffman, a professor of psychology at New York University and author of the forthcoming book, "Empathy, Justice and Moral Internalization," pointed out that one drawback of empathy is that people tend to empathize most readily with those who are similar to themselves in appearance, social circumstances, behavior and the like. "To the degree that one is very empathic toward one's own group, that may mean one is very hostile toward another group," said Dr. Hoffman. "So you get this paradox of empathy as a source of racism." Empathy encourages group identification, and groups often persist by pitting themselves against despised others.
But empathy does not always lead to cooperative bliss even within a given social group. Dr. Leslie Brothers, an associate clinical professor in psychiatry at University of California at Los Angeles, noted that humans are so primed to watch for nonverbal social signals in others, priding themselves on their empathic ability to slip easily into another person's head, that they often overinterpret body language and facial expression and impute negative meanings and motives where none exist. "We come to conclusions about the social signals we're reading, and it's easy to overemphasize our ability to accurately perceive what others mean," she said. "As a result, there's so much misunderstanding that goes on, with paranoia being the extreme example."
Moreover, it is possible to be overempathetic, so easily troubled by another's troubles that one becomes paradoxically fixated on one's own discomfort and seeks to escape from the person in pain. "One study showed that highly empathic nurses tend to avoid terminally ill patients," said Dr. Nancy Eisenberg, a psychologist at Arizona State University in Tempe.
In tracing the roots of empathy, researchers have considered a range of affiliative behaviors that may be the substrate on which full-bodied empathy is built. On the primitive end of the scale is mood contagion, the passing of an emotion or behavior through a group of animals. Mood contagion causes a herd of antelopes to start fleeing, wolves or dogs to start howling in unison, or people to start yawning when they see (or hear or read about) another person yawning. Contagious mood may explain why pets so often seem to their adoring owners to be empathetic: a dog picks up on his mistress' sadness and begins whimpering, for example. Infants in a neonatal unit will start crying when they hear another baby crying. Nor is it the loud noise alone that is upsetting them, said Dr. Hoffman. In studies using synthesized baby cries, or white noises of the same decibel as a cry, infants did not catch the crying bug to nearly the same degree as when they heard a real infant howl.
Higher on the empathy pyramid is something akin to social smarts, said Dr. Brothers, the ability to get hints about another animal's intentions from its gestures and behaviors. In parallel with the evolution of group living, primates began developing the neural and visual equipment necessary to read one another's facial expressions and body language. As primates evolved, said Dr. Brothers, the visual system became ever more connected to the emotional centers of the brain like the amygdala, the better to link what one sees in another to what one feels. "The amygdala became more and more connected with the visual senses and less with the sense of smell, and that kept step with primates having evolved to send each other visual signals like facial expressions," she said. At the same time, the auditory pathways linked up with the brain's emotional headquarters, the better to interpret vocalizations and eventually speech.
Many types of primates, apes and monkeys alike, use facial expressions to communicate with one another. When confronted with a stranger, a rhesus monkey will open its mouth and chatter its teeth, the better to say, "I don't like you and I wish you would leave."
Going beyond a mere reading of others is a mimicking of others, a skill that Dr. Robert W. Mitchell, a psychologist and animal behaviorist at Eastern Kentucky University in Richmond, calls "kinesthetic-visual matching," or imitation. Monkey-see, monkey-do is often used as a put-down, imputing stupidity, but in fact the ability to imitate another animal's movements or expressions ranks as a mark of intelligence, and monkeys are not very good at it, while some apes often are (hence the term, to ape). For humans, at least, engaging in facial imitation can lead to an empathic experience. That is because the muscles of the face are connected to the emotional centers of the brain. If you see somebody frown and you frown in response, you will feel more negative than you had a moment before; the opposite is true with a smile.
As it turns out, one animal that is especially adept at kinesthetic-visual matching is the dolphin, said Dr. Mitchell. If a sea lion is put in a tank of dolphins, the dolphins will start attempting to mimic the body posture of the sea lion. Dolphins swimming with human divers will coordinate the rate of their air bubbles to match those percolating from the diver.
Yet it is one thing to read and react to a variety of social cues, and another to express true empathy for a comrade in crisis. Many scientists believe that to truly empathize with another demands that one perceive oneself as an individual and relate personally to another creature's plight. To test whether an animal recognizes itself as itself, scientists give an animal a mirror and see how it reacts. Among monkeys, the response is clear and consistent: they do not recognize themselves in the mirror, instead treating the mirror image as another monkey and reacting with aggression or fear.
By comparison, the great apes like chimpanzees and orangutans show intriguing indications of self-recognition when given a mirror. They preen, they open their mouths and inspect their teeth; they use the mirror to look at their backsides, they play with their genitals and delight in their exhibitionism.
To further test for self-recognition, scientists have anesthetized chimpanzees and other apes and put a dot of paint somewhere on each animal's face. When again confronted with the mirror, the primates often try to wipe the spot off, recognizing it as a blemish they did not have a little while earlier.
Dr. de Waal said his observations indicate concordance between a species' capacity for self-recognition in a mirror and its likelihood of displaying compassionate, empathic behavior toward its fellows. Monkeys do not recognize themselves in a mirror, and they would never put an arm around the shoulder of a friend hurt in a fight, he said. Chimpanzees have been shown to do just that, and they also demonstrate signs of self-recognition.
He and others emphasized, however, that the meaning and validity of mirror self-recognition tests are sharply disputed among animal behaviorists. "Not all members of a particular species will recognize themselves in a mirror," said Dr. Mitchell. "Sometimes an animal will respond, but then months later it won't. The whole field is a mess right now, with everyone claiming their experiment is better than the others."
Dolphins, for example, show some sense of mirror self-recognition, but the question remains open whether they empathize with one another. They are a highly social species, and must reach cooperative decisions about when to fish, when to sleep and went to roam, and so empathy could help cement the group bonds that ease their communal negotiations. http://www.nytimes.com/1995/05/09/science/scientists-mull-role-of-empathy-in-man-and-beast.html?pagewanted=all
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