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Recently I wrote about grief in animals showing that many animals anguish over their losses and that we're not the only animals who bereave, display deep sadness, or who engage in rituals after losing close friends or loved ones. Now let's consider love, a troubling and mysterious emotion. People don't hesitate to say they love another human or nonhuman animal and then harm them. I'm glad they don't love me.
Animals feel a wide range of emotions, including each of Charles Darwin's six universal emotions: anger, happiness, sadness, disgust, fear, and surprise. It's important to remember that there differences among species in how they express their emotions (as well as perhaps in what they feel), and that there are also differences among individuals of the same species. Not all dogs or chimpanzees experience and express joy, grief, or jealousy in the same way. Research has shown that, as with humans, each individual has his or her own "personality." Animals can be bold, shy, playful, aggressive, sociable, curious, emotionally stable, or agreeable; they can be extroverted, introverted, dominant, or submissive. Individual and species differences make the study of animal emotions more difficult and challenging, but they also more exciting. As the saying goes, it takes all kinds of people to make the world go 'round, and the same is true about the different "personalities" within the social world of animals.
It's sometimes easier to see and understand emotions in animals than in humans because animals don't filter their emotions. What they feel is clearly written on their faces, publicized by tails, ears, and odors, and displayed by their actions. Animal emotions are raw and out there for all to sense — to see, hear, smell, and feel. Anyone can tell. For some, like the people who deliver packages to my home, it's a necessity.
Humans have struggled to understand and define love since the dawn of consciousness, so what possible hope is there that we can understand and define love in animals? And yet, though we don't truly understand love, we do not deny its existence, nor do we deny its power. We experience or witness love everyday, in a hundred different forms; indeed, grief is but the price of love. Since animals grieve, surely they must feel love too.
Love is perhaps the most complex of all emotions, given its bewildering variety of forms and shadings. On this landscape, where science and poetry meet, we find love that is romantic, parental, filial, and erotic, and we see love express itself as friendship, loyalty, affection, tenderness, devotion, commitment, and compassion.
If I were to chance a definition, one that we could use to examine animal behavior in search of love, I'd say that love means preferring the close company of another individual, seeking them out, and if necessary protecting and caring for them. It means forming and maintaining strong and close reciprocal social bonds and communicating your feelings with your loved ones. Not exactly poetry, but it's a start.
There's considerable evidence that many animals are capable of feelings that run the gamut of the varieties of love, and the latest science argues for the existence of love in many different species. The brain machinery of love — the microanatomy and neurochemistry that allow us to feel love — is similar or identical to that of numerous other animals. Once again, science is catching up with what our intuitions already tell us, and in the following sections, we will look at love that is romantic (that involves selecting and keeping a mate), maternal (that involves parent-child bonding), and filial (that involves love between siblings or friends).
Helen Fisher, author of Why We Love, put forth what she calls a "immodest proposal" concerning the evolution of love: "All these data lead me to believe that animals big and little are biologically driven to prefer, pursue, and possess specific mating partners; there is chemistry to animal attraction. And this chemistry must be the precursor to human love."
The most devoted mates are not necessarily our closest kin, the great apes, or other mammals. More than 90 percent of bird species are monogamous, and many mate for life. Fewer mammals are monogamous, and the nonhuman primates appear comparatively callous when it comes to commitment. Chimpanzee males, for example, don't spend much time courting, mating, or remaining with a female whose young they've fathered. When males aren't needed to provide protection or food for their mates or their offspring, they frequently try to mate with as many females as possible. Does that sound like any human males you know?
Animals communicate in a wide variety of ways including scent. Scientists may not be very adept at using their nose, but not so other animals. Scent can be a very powerful communicator, as is made clear in the following vivid description of a male elephant experiencing what is called "musth":
He is a hot-blooded, 30-year-old male in peak physical condition. He has mucus oozing from his cheeks and green urine streaming down his legs. His penis has a green sheen to it and he gives off a smell that can be picked up half a mile away. He wafts his ears back and forth and makes a low rumble. He looks confident: after all, many females find him irresistible. Sounds familiar? Hopefully not. He is a male elephant in musth — something like a state of rut. Sexually mature bull elephants go through musth for a one to two-month period every year. They don't exactly hide it, excreting a cocktail of chemicals from a bulbous gland on their cheeks that can swell to the size of a basketball, passing more than 300 litres of urine a day (equivalent to 24 buckets), and — not surprisingly — smelling like a herd of goats. What's more, during this dramatic advertisement of his sexuality the male appears to undergo something of a personality change; indeed, the word musth is derived from a Persian word meaning drunk. They become very aggressive and obsessed with sex, probably as a result of their high testosterone levels, which can increase by up to 60 times.
A male elephant in musth isn't an animal with whom you'd want to cross paths. What's interesting here is not only are there rapid and obvious personality changes during musth, but also that a male in musth can communicate his intentions clearly and openly to females in whom he's interested and to other males. "Musth is the elephant version of expensive aftershave and a flash car. It is thought to inform males and females alike of an elephant's age, status and reproductive health, and also increases a male's chances of reproductive success."l
The chemical that does it all is called frontalin, which is secreted by sweat glands in the elephant's cheeks and also shows up in their breath and urine. A male proclaims his intentions and prowess, females assess his reproductive fitness, and other males judge how strong he is before picking a fight. The precision of this signaling seems to be unique among mammals, but it's likely that non-mammals also use odors to show their intentions.
There's also compelling evidence that fish also make choices about mating. They're not automatons. University of Louisville biologist Lee Dugatkin has identified what he calls "guppy love." Dugatkin discovered that males change their behavior and become bolder in response to a predator when there is a female around, because females find bold males more attractive. Even among fish, it seems like males will risk it all for love.
In some instances animals are seen acting with incredible devotion and care even though there's no biological advantage to be had. Several years ago, a story appeared about two Jack Russell terriers who were found, filthy and terrified, cowering on the main street of a small town. The dogs were friends, not mates. One was bleeding from both eyes; the other was standing guard, barking and snapping at anyone who approached. They were taken to a veterinarian, who determined that the one terrier had been stabbed: both eyes had to be removed and the lids sewn up. Two days after the operation, Ben, as he had been named, was reunited with Bill in the local animal shelter. From that moment on, Bill acted as Ben's guide dog; with Ben holding onto the scruff of his neck, Bill walked him around the yard until he knew the lay of the land. After a TV crew captured this amazing performance, the two dogs found a marvelous home with an elderly couple who had an old female Jack Russell. With Bill's nudges and tugs, Ben quickly learned to negotiate the little house and garden. They sleep curled up together and behave "rather like a married couple."
Incredibly, this is not the only story of a sighted animal helping a blind animal: consider the tale of Annie, a blind mule, and her constant companion and guide Charlie, a steer. Both are permanent residents of Colorado's Black Forest Animal Sanctuary (BFAS), a nonprofit rescue organization. Annie was nursing a broken shoulder and bound for the slaughterhouse when BFAS volunteers bought her in. She lived at the ranch for over a year before she met Charlie. Initially, Charlie and Annie were kept in separate pastures, but during one cold spell all the livestock was herded into a single pen for warmth. Charlie hit it off with Annie. He started nuzzling up to her and playing with her. Today, the two are inseparable. Annie used to have a hard time finding the water tank, but Charlie unfailingly leads her to it. She follows him around the pasture, avoiding bumping into the fence, and as with Bill and Ben, they sleep cuddled up together.
There are numerous stories of animals of different species who form close social bonds that resemble what we call love. A one-year old hippopotamus, named Owen by his caretakers, formed a close bond with a century-old male tortoise named Mzee (Swahili for old man) after floods in Kenya (due to a tsunami in 2004) left Owen dehydrated and alone. Owen was found by wildlife rangers near the Indian Ocean and brought to a wildlife sanctuary in Mombassa. Owen now sleeps and eats with his tortoise friend, and the two have remained inseparable, close buddies.
As we all know, dogs are "human's best friend." Their devotion to humans is undeniable. They can also be best friends to one another. I'd like to end this section on love by sharing the story of two beautiful malamutes, Tika, and her longtime mate, Kobuk, who had raised eight litters of puppies together and now were enjoying their retirement years in the home of my friend Anne, who shared their story with me. Kobuk was charming, energetic, and always demanded attention. He'd always let you know when he wanted his belly rubbed or his ears scratched. He also was quite vocal and howled his way into everyone's heart. Tika, Kobuk's mate, was quieter and pretty low-key. If anyone tried to rub Tika's ears or belly, Kobuk shoved his way in. Tika knew not to eat her food unless it was far away from Kobuk. If Tika happened to get in Kobuk's way when he headed to the door, she usually got knocked over as he charged past her.
Then one day a small lump appeared on Tika's leg. It was diagnosed as a malignant tumor. Overnight Kobuk's behavior changed. He became subdued and wouldn't leave Tika's side. Then, Tika had to have her leg amputated and had trouble getting around. Kobuk, clearly worried about her, stopped shoving her aside and stopped minding if she was allowed to get on the bed without him.
About two weeks after Tika's surgery, Kobuk woke Anne in the middle of the night the way he did when he really needed to go outside. Tika was in another room, and Kobuk ran over to her. Anne got Tika up and took both dogs outside, but the dogs just lay down on the grass. Tika was whining softly, and Anne saw that Tika's belly was huge and swollen. Anne realized that Tika was going into shock, so she rushed her to the emergency animal clinic in Boulder. The veterinarian operated on her and was able to save her life.
If Kobuk hadn't fetched Anne, Tika almost certainly would have died. Tika recovered, and as her health grew after the amputation and operation, Kobuk became the bossy dog he'd always been, even as Tika walked around on three legs. But Anne had witnessed their true relationship. Kobuk and Tika, a true old married couple, would always be there for each other, even if their personalities would never change. They were love dogs doing for each other what needed to be done.
We all have great stories of love and devotion in a wide variety of animals. We would be wise to follow our animal friends' example of commitment, devotion, and love. We shouldn't be so self-centered and arrogant to think we're the only species in which love has evolved, is openly expressed, vigorously sought, and sorely needed. (Many other examples of love can be found in The Smile of a Dolphin in which my colleagues share their own stories of animal love and other emotions based on years of research on a wide variety of species, The Emotional Lives of Animals (that contains these and other stories), The Animal Manifesto, and Pleasurable Kingdom.
