Last spring I came to know a pair of pigeons. I’d been putting out neighborly sunflower seeds for them and my local Brooklyn house sparrows; typically I left them undisturbed while feeding, but every so often I’d want to water my plants or lie in the sun. This would scatter the flock—all, that is, except for these two.

One, presumably male, was a strapping specimen of pigeonhood, big and crisp-feathered in an amiably martial way. The other, smaller bird presented a stark contrast: head and neck feathers in patchy disarray, eyes watery, exuding a sense of illness that transcends several hundred million years of divergent evolution.

She didn’t have the energy to take wing as I approached. Instead she’d take several desultory steps away. Her mate would fly to the deck railing, where he paced back and forth. He gave every impression of wanting to flee—but not without his mate, at whom he looked back with apparent concern. This caught me by surprise. I spend a fair amount of time watching animals and writing about them—not just about their populations or interactions or physiologies, but about their minds, what they might think or feel—yet I hadn’t much tried to put myself in a pigeon’s feathers, so to speak.

Moreover, I slipped into that easy habit of interpreting behaviors through a narrowly evolutionary lens, assuming their decisions to be coldly calculated to maximize reproductive success. From which perspective the male’s loyalty made little sense: Better for him to fly off and find another, healthier mate with whom to pass on his genes, than to stick around with this sick bird.







Also in Animals Parasites Are Us By Robert V. Levine Jerry Coyne is an evolutionary biologist at the University of Chicago. His research on population and evolutionary genetics has been widely published in professional and trade journals and his 2009 book, Why Evolution Is True, established him as a leading...READ MORE

Of course, I wouldn’t frame my own life that way. Where I have meaningful feelings, they would have imperatives. Yet as I watched Harold and Maude, as I so unoriginally named them, their drama unfolding beside murals my girlfriend and I had painted as expressions of our own feelings, I began to wonder. Harold behaved in a manner expressive of devotion, tenderness, and affection: the foundations of what in humans we call love.



“I’ve known mourning doves who were more in love than a lot of the people I’ve known.”

It’s a word not often associated with pigeons, or even other animals. “Our highest esteem is accorded romantic love, which is considered the most suspect to ascribe to animals,” writes Jeffrey Moussaief Masson in When Elephants Weep: The Emotional Lives of Animals. Indeed, science for most of the last several centuries would have found the suggestion risible, suggesting instead that Harold felt—if pigeons could even be said to feel—some instinctive, unconscious urge to stay nearby, an urge with no more emotional resonance than an itch.

Love, after all, is central to the human condition. How could a creature with a brain the size of a bean possibly feel something so profound? Something that gave rise to Romeo and Juliet and “Unchained Melody” and the Taj Mahal?

Part of the reluctance to talk of bird love, I suspect, is rooted in our misgivings about our own love’s biological underpinnings: Is it just chemicals? A set of hormonal and cognitive patterns shaped by evolution to reward behaviors that result in optimal mating strategies? Perhaps love is not what defines us as human but is something we happen to share with other species, including the humble pigeon.





City dwellers often see pigeons as an eyesore and a nuisance. The more nature-inclined regard them as marvels of natural history and urban adaptation. Descended from birds bred by European hobbyists, Columba livia now nest on building ledges rather than their ancestral cliffs. They scratch out sustenance from refuse, handouts, and the seeds of weeds, become symbols of a certain indomitability.

But can pigeons be in love? Considering the possibility, it’s worth stepping back and looking at where society and its knowledge-defining practices now stand in regard to the notion of nonhuman thoughts and feelings.

The old habit of treating other animals as so many furred and feathered automata—Descartes famously likened animals to clocks—is in fast recession. Scientists talk regularly about animal intelligence. But that automatic habit shaped scientific discourse and public imagination. Every assertion of complex experience could be met by the default rebuttal of anthropomorphism: Might we merely be projecting human qualities onto something much simpler, even alien?

Its legacy is still felt. Animal consciousness tends to be most appreciated in a select class of animals: big-brained creatures like great apes or whales, or domestic companions like cats and dogs, who can’t be ignored. As a class, birds receive comparatively little attention. And when they do, it tends to focus on intelligence, on easily quantifiable feats of problem-solving and cognition, rather than emotion. Most anyone who follows science knows about brainy crows using tools and high-level reasoning. But avian love remains beyond the pale.

Part of the reluctance to talk of bird love is rooted in our misgivings about our own love’s biological underpinnings: Is it just chemicals?

A telling example is Partnerships in Birds: The Study of Monogamy, a collection of studies published in 1996 with the express intent of explaining why birds are monogamous, which makes not a single mention of emotion. Affection appears once, in connection to a brief mention of attachment in so-called pair bonds between mates; attachment, readers are reminded, need not be understood in potentially loaded terms of strength or weakness, but rather measurements of “proximity and synchrony of behaviours which may influence fitness.” It’s a fascinating book, but also slightly ridiculous, like watching old video of lawn tennis matches, in which custom dictates the players wear white slacks and not run too hard.

The conservatism is understandable: Feelings are hard enough to measure in humans, much less animals, and “you can’t think of birds as little humans,” says Kevin McGowan, a Cornell University ornithologist who specializes in the social behavior of crows. Yet evolution is conservative too, notes McGowan, shaping the animal kingdom’s diversity from common biological elements. Of emotions, McGowan says, “there’s no reason to think that we humans have some brand-new thing.”

Indeed, love’s essential biology is evolutionarily ancient. Oxytocin and vasopressin, the hormones most closely associated with mammalian bonding, have the near-identical avian analogues of mesotocin and vasotocin, which shape the interactions of zebra finch couples. Birds likewise possess the basic reward-system neurotransmitters serotonin and dopamine. Birds might not have much in the way of easily recognizable facial expressions, but their biochemistry’s symphonic chain reactions play out in neurological structures that evolved early in life’s history, long before the cerebral cortex itself.



That alone is no guarantee of romance. Jane Goodall, the legendary primatologist who so powerfully described the abiding love of chimpanzee mothers for their children, has written that she cannot conceive of our closest living relatives as experiencing anything comparable to romantic love. To Goodall, chimp courtship is too brief to permit deep feelings. Their proclivities, she has noted, were not shaped by evolutionary circumstances conducive to love, namely long-term relationships with single partners, which are the norm for modern humans.

In this respect we diverge markedly from chimpanzees—but not from birds, in whom monogamy is found in some 90 percent of all species, including pigeons. Neither their nor our monogamy is a pure, idealized sort, exclusive of infidelity or a succession of partners. Extra-pair copulation, or what we call cheating, can be quite common. But monogamy is the baseline and pigeons, who frequently mate for life, are among the more fidelitous of birds. Within the evolutionary context of monogamy, a capacity for love makes perfect sense.

Monogamous couples share food, information, and offspring-rearing duties, especially in species whose young are born requiring constant care—as is the case with pigeons, their helpless chicks so carefully hidden that few city-dwellers have ever seen one. Love—an attentiveness to the needs of another being, reinforced by emotional rewards—should enhance cooperation and improve a couple’s chances of raising healthy offspring. And as noted by Claudia Wascher, a zoologist at Anglia Ruskin University, whose Ph.D. research described how mated greylag geese have lower levels of stress hormones than single birds, there’s no question that pair bonds are powerful.

“Social bonds in general seem to be terribly important for birds,” says Wascher, “and the most important social bond for most birds is the pair bond.” Monogamy, then, should be fertile evolutionary ground for love’s blooms.





McGowan and Wascher readily recognize emotion in birds. “I would suspect they do have affection for each other,” says McGowan, who has observed crow couples stay together for more than a decade. “It’s not going to be the same as what humans have, but I suspect it’s close enough that we’d recognize it,” she says. Yet McGowan stops short of love: Science describes behaviors easily, but is in murkier terrain with complex states of mind.

Indeed, it might seem a flight of fancy to equate pair-bonding’s neurobiological rewards with love, no matter how much evolutionary sense it makes. Pigeons have the necessary pieces and life history, but can their experiences of bonding really compare to what in humans inspired eighth-century poet Chang Chi’s lamentation of the unrequited: “So I must give you back your pearls / with two tears to match them”? Can pigeon-brained attachment manifest in love’s full spectrum, from butterflies-in-the-stomach infatuation to the ecstasy of consummation?

It’s still possible, however, to imagine that avian love is more than a mindless itch. Perhaps human love is unusually complex, invoking not just physiology but our unique cognitive sophistication. Still, many species display a cognitive complexity—awareness of self and others, long-term memory, a capacity for abstract concepts—comparable to primates. The gentle social courtship of “allopreening,” in which birds groom one another’s feathers, is especially sophisticated. Just as I can think fondly of my lover while she’s away, so might a pigeon think fondly of its absent mate.

Ubiquitous and unappreciated, typically ignored or regarded as dirty, annoying pests, pigeons mean something else to me now.

We can consider observational evidence to buttress the biological. About a decade ago, Rita McMahon found a pigeon with a broken leg on her deck in New York City’s upper west side. The pigeon was otherwise quite fortunate. McMahon would go on to cofound the Wild Bird Fund, which cares for some 3,500 sick and injured birds every year. A veterinarian amputated the pigeon’s leg; while it recovered, it would rest on a cushion in McMahon’s apartment window. On the other side stood her mate, day after day, keeping her company until she was released and the couple rejoined.

“They were devoted to each other,” says McMahon, who also recalled how one of her volunteers once found a broken-winged robin in a depression in a snow bank, his mate nearby. The volunteer picked up the injured bird and put him in a bag for transport to the hospital. With little fuss she then gathered the mate—which was quite unusual, as healthy wild birds are uniformly skittish. “I understand being able to pick up a broken-winged robin easily, but not one who’s intact,” MacMahon says. At the hospital, they learned that the break wasn’t fresh. The robin was in surprisingly good health. His mate, believes MacMahon, had been taking food to him on the snowbank, “and decided to stay with her man.”

Love is as love does. “There’s no reason to think it would be much different for humans than nonhumans,” says Marc Bekoff, author of The Emotional Lives of Animals. “I’ve known mourning doves”—a species closely related to pigeons—“who were more in love than a lot of the people I’ve known.” To Bekoff, love’s ultimate measure is the presence of its converse, grief.







Apparent grieving exists in the avian world, most notably among greylag geese, in whom individuals who’ve lost a partner display the classical symptoms of human depression: listlessness, a loss of appetite, lethargy lasting for weeks or even months. The same applies to pigeons. On Pigeon Talk, a website of pigeon-breeding hobbyists, anecdotes abound of birds sinking into a funk after losing their mates, and sometimes refusing to take another mate for up to a year afterward—no small time for a species that typically lives for less than a decade.



One of the most moving stories involves mourning doves. After a dove was eaten by a hawk in the backyard of a forum member called TheSnipes, the mate stood beside the body for weeks. “I finally couldn’t stand to watch it any more and picked up every feather and trace of remains that was left there and got rid of it,” wrote TheSnipes. “The mate continued to keep a vigil at that spot though, for many months, all through the spring and summer.”





McMahon noted something I hadn’t considered: There are good and bad pigeon couples. Some are attentive and physically affectionate, constantly stroking one another’s feathers. Others appear distant and peckish. As human love varies, so might theirs. Not every pigeon’s tale need be so romantic as Fly High, Fly Low, Don Freeman’s delightful children’s book about the search of Sid for his mate Midge, lost to him—though only for a while—when workers take down the sign in which they’ve made their nest. Others might better resemble Maud and Claud of Patricia Highsmith’s “Two Disagreeable Pigeons,” regarding each other with pique and scorn, kept together by inertia and habit.

It’s also worth considering whether pigeons might experience aspects of love that we don’t. Could a bird whose basic physiology adapts to changing seasons, who can perceive atmospheric infrasound, and see Earth’s magnetic field, have emotional capacities beyond our own? Including, perhaps, forms of love that are not merely analogues of our cherished feelings, but something unique to them?

It’s something to imagine. “Love among animals might appear as mysterious and baffling as human love has over the centuries,” writes Masson.

At risk of sounding unromantic, though, I’m not convinced that love is so mysterious. It just feels good.

As for Harold and Maude, I don’t know how their story ended, or indeed whether it continues. They roosted in a partially abandoned building on my fast-gentrifying block. It’s now being turned into condos, making them victims of Brooklyn’s rising real estate prices, albeit with a better chance than most humans at finding a decent place to live nearby.

Their example stayed with me, though, and now colors the way I think of my winged neighbors. Ubiquitous and unappreciated, typically ignored or regarded as dirty, annoying pests, pigeons mean something else to me now. Perched on building ledges, chasing scraps of food, taking to the skies at sunset: Each one is a reminder that love is all around us.





Brandon Keim is a freelance journalist who writes about nature, science, and technology. His work has appeared in Wired, Aeon, Scientific American Mind, and other publications.