Tamed and Untamed

by Sy Montgomery

  Harris Center for Conservation Education Science Director Brett Amy Thelen told me about the black bear who ransacked campers’ coolers and, with teeth and claws, punctured and drank thirty-six cans of Rainier beer before passing out in a tree at the Baker Lake Resort in Washington State. (He drank one can of Busch but then went back to his favorite brand.) His preference was so strong that when the fish and wildlife department had to relocate him, they baited the trap with the usual doughnuts and honey but also added—you guessed it—Rainier beer. And they caught him.

  When I spoke with her, Thelen had been researching intoxication in the animal kingdom in preparation for a talk as part of the center’s popular series, Nature on Tap, at our local inn. (“What better topic for a happy hour talk?” she reasoned.) Some of the stories she’s heard are apocryphal: Elephants don’t get drunk on rotting fruit lying on the ground. (That one was debunked by a University of Bristol study: Elephants eat the fruit off the tree before it has time to ferment.) But birds can and do get drunk from eating fermenting fruit, she told me. The problem was so severe among Bohemian waxwings feasting on rotting mountain ash berries one year that in the capital of Canada’s Yukon Territory, the local environmental agency had to set up a drunk tank (actually a plastic hamster cage) where people could bring birds who needed to safely sleep it off.

  Why would vulnerable birds purposely impair their nervous systems in this way? They aren’t getting drunk on purpose. They’re just trying to eat a lot of fruit to prepare for winter, and that winter there was a glut of berries. The birds were essentially poisoned by what looked like good, healthy food.

  But interestingly, other animals seem to seek out intoxicating substances for the same sometimes complex, sometimes stupid, and occasionally edifying reasons we do. Thelen and I traded more stories. I had a few of my own.

  Ever hear of courage in a bottle? Apparently the colorful baboons known as mandrills know just where to find it. In Animals and Psychedelics, researcher Giorgio Samorini reports that in Gabon, a male mandrill will often prepare for combat with another male by eating the root of the iboga plant. He waits two hours for the drug to take effect before attacking his rival. “The fact that the mandrill waits like this,” the author writes, demonstrates “a high level of awareness of what he is doing.”

  Feeling rejected by the opposite sex? Certain fruit flies respond by drowning their sorrows in booze. University of California neuroscientists allowed some male flies to mate with females, but placed others with females who had already mated so would reject new suitors. Those who were sexually rejected were four times more likely to choose food vials containing alcohol than flies who had had scored with the ladies.

  And then some animals may simply be experimenting with intoxication to experience an alternate reality. A BBC team filmed groups of young bottlenose dolphins playing with a particular species of poisonous puffer fish. Each dolphin would gently squeeze the fish in his or her mouth, causing the fish to release a hallucinogenic toxin. Then the dolphin would pass the fish to a neighbor, almost like a person passing a joint. Afterward the dolphins would stare at the water’s surface as if mesmerized by their reflections.

  Do Animals Dream?

  — Sy —

  The electric eel exhibit at the New England Aquarium has a feature that makes it a favorite. Whenever the eel is hunting or stunning prey, the charge powers a voltmeter above his tank. It lights up when the eel is using his electricity, and allows you to see the invisible—like magic.

  One day I saw another magical thing happen in the tank. Thanks to the voltmeter, I was able to watch the eel dream.

  It happened when I was standing in front of the exhibit with Scott Dowd, the lead aquarist for the freshwater gallery, watching the eel resting motionless at the bottom of the tank.

  “I think he’s asleep,” I said to my companion.

  “Yes, that eel is catching some serious z’s,” he agreed.

  Being hard-core fish enthusiasts, we continued to watch transfixed while the electric eel slept. And that’s when it happened: A big flash shot across the voltmeter display—and another and another.

  Electric eels hunt while swimming forward, wagging their heads to and fro, sending out electric signals that bounce back to them, sort of like a dolphin’s echolocation. But he was still motionless. So what was the flash for?

  “I thought the eel was asleep!” I said to Dowd.

  “He is asleep,” he replied.

  We realized at once what we were almost surely witnessing. The electric eel was dreaming.

  “It would appear that not only do men dream,” Aristotle wrote in History of Animals, “but horses also, and dogs, and oxen; aye, and sheep and goats. . . .” It was obvious: Like most of us, Aristotle had watched sleeping dogs twitch their ears, paddle their paws, and bark in their sleep. Surely other animals dreamed as well.

  But since Aristotle’s day, more “modern” thinkers denied that animals could dream. Complex and mysterious, dreams were considered the exclusive province of so-called higher minds. As brain research advanced, however, researchers were forced to concede that Aristotle was right. Animals do dream. And now we are even able to glimpse what they dream about.

  Since the 1960s scientists have understood that our dreams happen during the rapid eye movement (REM) phase of the sleep cycle. During this time our muscles are normally paralyzed by the pons of the brain stem, so that we don’t act out our dreams. In 1965 researchers removed the pons from the brain stems of cats. They discovered the cats would get up and walk around, move the head as if to follow prey, and pounce as if on invisible mice—all while asleep.

  By 2007 we would get an even more vivid picture of animals’ dreams. Massachusetts Institute of Technology scientists Matthew Wilson and graduate student Kenway Louie recorded the activity of rats’ brains while the animals were running a maze. Neurons fire in distinct patterns while a rat in a maze performs particular tasks. The researchers repeatedly saw the exact same patterns reproduced while the rats slept—and they saw this so clearly they could tell what point in the maze the rat was dreaming about and whether an individual rat was running or walking in his dreams.

  The rats’ dreams arose from the hippocampus, the same area in the brain that seems to drive humans’ dreams. It’s an area known to record and store memories, and that supports the notion that one important function of dreams is to help us remember what we have learned.

  Of course, it’s important to a lab rat to remember the right way to run a maze. So if rats dream of running mazes, what do birds dream about? Singing.

  University of Chicago professor Daniel Margoliash conducted experiments on zebra finches. Like most birds, zebra finches aren’t born knowing their songs; they learn them, and young birds spend much of their days learning and rehearsing the song of their species. While awake, neurons in the forebrain known as the robustus archistrialis fire when the bird sings particular notes. The researcher was able to determine the individual notes based on the firing pattern of the neurons. While the birds were asleep, their neurons fired in the same order—as if they were singing in their dreams.

  Much less work has been done on fish than on mammals and birds. No one has found REM sleep in fish—yet. But that does not mean they don’t dream. Interestingly, no one has discovered REM sleep in whales, either. But whales almost surely dream. They are long-lived, social animals with very big brains much like our own, and for whom long-term memory consolidation is crucial. And if you were looking for rapid eye movement in sleeping owls, you’d never see it—because owls’ eyes are fixed in their sockets. That’s why they need to turn their heads around, Exorcist-style. Yet owls’ brain waves show they dream, too.

  Fish do sleep, however—that much is well known. It’s been carefully documented that if zebra fish are deprived of sleep (because pesky researchers keep waking them up), they have trouble swimming the next day—just as a person
would have trouble concentrating after a dreamless night.

  What might an electric eel dream about? The voltmeter at the New England Aquarium showed us the answer: hunting and shocking prey.

  Window to the Wild

  — Sy —

  We couldn’t figure it out. Many nights a week—sometimes at midnight, sometimes 2:00 or 4:00 a.m.—our border collie, Sally, who slept all night in our bed with us, suddenly erupted into explosive barking. Since she slept with her head on our pillow, her voice was directly in our ears. Naturally we longed to discern the cause of her excitement. But her voice was so loud we couldn’t hear anything else.

  One cold night I got up and went outside to look around. There was a fox standing in the street, looking up at our bedroom window and screaming.

  Now I understood. This was a dispute about the Smell Lane.

  The Smell Lane is what I call the route of Sally’s and my morning walk together. It runs through a neighbor’s backyard, crossing a footbridge over Moose Brook, though a woods of ferns and hemlocks before going over a second footbridge and circling back toward home. Lots of animals use this route, and I always look for signs: the paw prints and tail drags of mice, the scales of pinecones left by red squirrels, the half-moons of deer hooves, the dino-prints and black-and-white scats of turkeys (you can even tell the sex of the individual who left it—the males’ are J-shaped).

  But it’s Sally who knows them all. A dog’s sense of smell has been estimated to be 10,000 to 200,000 times as acute as our own. Experts have likened dogs’ scenting superpowers to being able to taste a half teaspoon of sugar in an Olympic swimming pool of water (per Barnard College dog researcher Alexandra Horowitz), or being able to see an object three thousand miles away (per James Walker, formerly of Sensory Research Institute). Sally stops many dozens of times on our half-hour walk to carefully smell who was there. How I wish she could tell me what she knows!

  All dogs are interested in smelling the world, and some—coonhounds, search-and-rescue dogs—are professionals. But I had never met an amateur who was as interested as Sally, especially a female. It may have had to do with her past. Before she came to us, we were told, Sally came from a “bad neighborhood.” Did this mean she came from a town known for crime or drug use? Low test scores in the schools? No, we were told: The neighborhood was bad because it was full of coyotes. We learned Sally had often run away from her previous owners. But she was lucky to return, because there were so many coyotes where she lived that not only cats but also dogs were known to have fallen prey to these wild canids—actually crosses between western coyotes and northern wolves, combining the adaptability and smarts of the coyote with the strength and group culture of the wolf.

  For Sally, knowing all the individuals of different species in her old neighborhood may have been a matter of life and death. Hence, perhaps, her unusual preoccupation with the comings and goings along the Smell Lane. The fox screaming beneath our window was surely somebody she knew. And who knew her. Though they had never met, they had been carrying on a meaningful correspondence.

  Foxes, who like wolves and dogs are canids, hold territories (one hundred acres or more); in summer they may be protecting their dens, and in winter, when their diet changes from mainly berries and insects to birds and small mammals, they are probably posting keep out on their hunting grounds. They mark the boundaries of their territory by spraying urine on prominent rocks and trees and, less frequently, leaving piles of their small-dog-like feces. The scent of fox urine is so strong even I could detect the sweet, skunky scent along our walk. And I had noticed that Sally made a point of marking over these keep out signs. (She marks more than any female of any species I have ever known.)

  So this, I suspect, is what brought the fox to scream at our dog from under our bedroom window those nights: Sally had been wrecking the fox’s keep out signs, and the fox was having none of it.

  Our domestic animals can straddle two worlds: those of their human families, and those of their animal neighbors. Sometimes they can tell us about the larger, wilder world outside our walls and windows. Once, avian intelligence researcher Irene Pepperberg, now of Harvard University, took her famous talking African grey parrot, Alex, home with her from the lab. Alex had been taught to speak English meaningfully and knew hundreds of words. From his trainer’s picture window, Alex looked out and saw, for the first time in his life, an owl. He began to scream, “Want to go back! Want to go back!” Alex knew, from instincts stretching back millions of years, to the ancestors of parrots and the ancestors of owls, that owls are dangerous predators. He was telling his trainer about his ancient, instinctual knowledge in a human language he learned in a twenty-first-century university laboratory.

  And this is one of the many miracles of living with even the most common of pets. Once in a while they can give us a glimpse of the unseen lives of our unknown neighbors—wild animals who are near at hand but, at least by humans, are little understood.

  As for our Sally, foxes no longer wake her in the night; she’s gone deaf with old age, not uncommon with border collies. But she doesn’t miss much. Every morning she and I still walk the Smell Lane, where, with her exquisite nose, she reads the morning mail.

  Different Information

  — Liz —

  It’s difficult to summarize how any individual animal perceives the world, but it’s extra difficult to do this for dogs in general. No other species, not even our own, can approach the dog in physical variety—a big Great Dane can be over three feet tall at the shoulder and weigh about two hundred pounds, yet it belongs to the same species as the Chihuahua, six inches at the shoulder and weighing maybe nine pounds.

  So to start with vision, your height makes a difference. Just as you can see farther when up on a ladder than when standing on the ground, so can a Great Dane see farther than a Chihuahua, a fact I notice every day when outdoors with my Chihuahua, whose visual world doesn’t go beyond the lawn, or even much beyond his little nostrils when we’re in long grass. If you lie on your side with your head on the ground, you’ll get an idea of his range. He therefore isn’t informed by vision as much as are those who are taller.

  How about hearing? Here he does better. When he hears a meaningful sound, he turns to face it just as we would, as if to see what made it, and he’s sensitive to sound even when he’s sleeping. At night he sleeps in my bed under the covers, and if he hears a suspicious noise he leaps up barking.

  Of course, dogs are best informed by scent, and as we all know their sense of smell is vastly better than ours. What’s interesting about this little dog, therefore, is his realism about scent information. When he’s in my office and hears something, he jumps up to look out the window, sniffing as he does. Thus he opens his eyes, his ears, and his nose to any evidence he can collect about what he’s just heard.

  This changes when we go outside. There the world of odors is readily available, and he runs here and there with his nose to the ground, or, because he grew up in a city and is a city dog at heart, he also goes to my car and sniffs the tires.

  It makes sense if you think about it. A sight or sound can vanish in an instant, but a scent will cling. A sight or sound may be experienced quickly and tends to transmit just a tiny, very specific amount of information—often more than enough to tell you what you need to know. But it doesn’t compare to a scent, as a scent remains available for a long time, and just one sniff can load you with all kinds of information.

  Let’s say you look out the window and think you glimpse a mountain lion in your field. You gasp and run out the door and around the house to see it better. The dog runs with you. But by then nothing is there. You, the human, see and hear nothing, the ground is dry and hard, and if in fact there was a mountain lion, it left no tracks.

  For all you know, the whole thing was an illusion. But while you stand there, looking around and wondering, the dog learns that a very large cat has just passed by, a female
about four years old with kittens for whom she was lactating; that she had eaten recently, not fresh meat but carrion from a carcass, probably a small animal; and that she moved her bowels not long before you saw her, so there’s a scat in the woods, maybe five hundred feet from where you’re standing.

  You are (in this case) a mature human being with a college degree, and your dog is just a little nobody, utterly dependent on your care. But in the end, who knows more about your surroundings? You or him?

  My favorite story about the power of scent involves our marvelous veterinarian, Chuck DeVinne. He’s also my neighbor, and once when he was away on a trip, his dog went missing. Now and then his dogs escape, and usually they come by my house, but since I hadn’t seen them I was afraid that Chuck’s dog was lost. The entire neighborhood went on high alert, but our vision and hearing gave us nothing.

  But Chuck knew what to do. As soon as he got home he collected the clothes from his trip that were to be laundered and bundled them into his car. He ran the motor with the heat on until the car was hot and the contents were warmed, then he opened the windows and drove slowly through the area where the dog was last seen. His scent poured from the car for the wind to carry. It clung to the bushes along the road that led to his house, and his dog found her way home quickly.

  Does Anybody Know What Time It Is?

  — Sy —

  As I write this, I am preparing to leave on a two-week book tour—sadly, without our elderly border collie, Sally. She loves our shared husband, and he loves her, but as a formerly neglected rescue who now rules the roost, she prefers that both of us stay home to staff her empire. Will the two weeks we’re apart feel like an eternity to her?