In 1958, as part of a research project on wolves, David Mech, a graduate student in wildlife ecology at Purdue, was flying over Isle Royale National Park, on Lake Superior. From above, he saw a wolf pack capture and kill a moose. This was rare. More than nine times out of ten, he had witnessed the wolves’ prey escape. “I wanted to see how old this moose was, and to see if it was ill,” Mech told me recently. He had the pilot drop him off some distance away, and snowshoed in. “I remember arriving to the edge of this clearing, and there were these fifteen wolves feeding on this moose,” he said. He didn’t know how the wolves would react when they saw him. “Long ago, when I started, we knew very little about wolves in the wild. We knew that they lived in packs, that they preyed on large animals, and that they howled. And the standard things from storybooks.” Upon spotting him, the wolves ran off, leaving behind the moose carcass. “They could have attacked me,” he said. “They could have had something more to eat!” The wolf, as he later described it in print, is “one of the wildest and shyest of all the animals in the northern wilderness.”
The Isle Royale study, which was started by Durward Allen, a celebrated biologist, was one of the earliest major studies of wolves in their natural setting. (It was inspired in part by “The Wolves of Mt. McKinley,” a monograph published by Adolph Murie, in 1944. Murie had been asked by the National Park Service to look at the relationship between timber wolves and Dall sheep in the area; Murie, after walking thousands of miles over three summers, concluded that the various fauna populations—including caribou and grizzly bears—were keeping one another in balance. A decade later, the Park Service instituted protections against wolf-eradication efforts there.) Moose had been known to have come to Isle Royale in the early twentieth century; the wolves had first arrived in the late nineteen-forties, having crossed an ice bridge from Canada. The island was only two hundred and ten square miles, and the wolves tended to follow waterways and shorelines, which made it easier to keep track of them. Scientists flying overhead in winter could see their footprints in the snow.
In 1970, Mech published “The Wolf: The Ecology and Behavior of an Endangered Species.” The book assembled an enormous amount of research on wolves, covering aspects including wolf habits, wolf society, and the relations of the wolf to prey, to non-prey, to disease, and, of course, to humans. The book became a best-seller and a foundational text, one that was read both by scientists and by laypeople. In time, however, Mech became less than pleased with the book’s ongoing success. “That was what we knew at the time, but I’d say we’ve learned more about wolves since that book’s publication than we had in all of previous history,” he told me. The book remained in print, even though Mech asked many times that it no longer be published. What bothers him most is the section he wrote on pack order.
Mech had relied on research done on captive wolves. The main study at the time was by Rudolph Schenkel. “It was logical to pick up Schenkel’s work,” Mech said, which laid out the terms “lead wolf” and “bitch wolf,” the antecedents of “alpha male” and “alpha female.” Schenkel wrote, “Every mature wolf has an ever ready ‘expansion power,’ a tendency to widen, not his personal territory, but rather, his own social behaviour freedom.” He added, “The maintenance of a not-quite-classless status requires constant self-assertion.” Schenkel also believed that wolves needed an outlet for aggressive energy, typically “released at the weakest individuals of the society.”
“It turned out all that stuff was mostly wrong,” Mech said. In 2022, his publisher agreed to stop printing the book. Yet, although field biologists no longer use the terms “alpha” and “beta,” they have proved too useful for humans to drop—now we use them in relation to our own groupings and conflicts.
Mech, a senior research scientist for the United States Geological Survey, has now been studying wolves for sixty-three years. “It was the next study, in Minnesota, that the whole field of radio-tracking started up,” he said. Researchers were able to follow wolves individually. “Each collar had its own radio frequency. So you could ‘tune in’ to an individual wolf, see where they were.” This level of detail opened up the field to all sorts of new research questions. “It wasn’t until the early seventies, after we’d put those radios on wolves and we could follow each individual that we realized, Oh, a pack is a family.” It began to make more sense, in general, to think of the heads of the packs as the breeders—the parents.
Different wolf populations have packs of different sizes, but the basic structure is the same: a mom, a dad, and their offspring. Sometimes the one-year-olds set out on their own, hoping to find a mate and start their own pack; sometimes they stick around and, as yearlings, help raise the next set of pups. As Kira Cassidy, an associate research scientist with a National Park Service research program in Yellowstone, explained, “The wolves generally in those dominant positions are not there because they fought for it. It’s not some battle to get to the top position. They’re just the oldest, or the parents. Or, in the case of same-sex siblings, it’s a matter of personality.” Cassidy specializes in wolves’ sociality, both within and between packs. Wolves do fight one another—in Yellowstone, where humans can’t hunt them, fights are the primary cause of mortality—but most fights are between packs, for territory. “In Yellowstone, maybe because there’s a lot to eat and it’s a protected area, our packs are larger, more complex family units,” she said. Where conditions are harsh, a wolf pack might number four—two parents, two pups—because so few pups survive. In Yellowstone, a pack often includes aunts, uncles, and sometimes even more than one breeding pair.
Cassidy said that one finding that surprised her came when she looked into battles between packs. She suspected that pack size would be important in determining victors. “We found that even more important than pack size was whether a pack had an old individual, male or female,” she said. At six years old, a Yellowstone wolf is considered an elder—only about one in five lives to that age. “If they have one or two older individuals, they are more likely to win—which was not what we’d expected to find.”
After that, she looked into the literature on other animals, and discovered similar findings. In times of droughts, elephant herds with a matriarch older than thirty-five do better. When there’s a salmon shortage, orcas follow the grandmother. “In the pack fights, we see that the elders don’t panic,” Cassidy said. “It seems to match up with this idea of them having past knowledge that helps the pack. They can ease their pack mates and bring them together. Or maybe the older ones help the pack avoid fights that they know they can’t win—which brings up their winning rate over all.”
When Mech published his book, even after more than a decade of field research, he had only once come within fifteen feet of a free-range wolf. On that occasion, he had accurately predicted the progress of a pack along a winter route, and had hid, along with others, in an old fish house nearby. One of the wolves calmly stared at the crack through which the researchers were taking photographs, and Mech was struck by the wolf’s countenance, “like that of a big friendly dog.” The close encounter was not particularly valuable, scientifically, but it inspired him to learn more.
“I had heard that there was one place on earth where wolves were unafraid of people,” he said. This was on Ellesmere Island, in Nunavut, Canada, just south of the North Pole. The pale wolves of the area are sometimes called white wolves, sometimes polar or Arctic wolves. In 1986, he got a contract from National Geographic to go there for a story. “I ended up going up there for twenty-four summers,” he said. He would usually be there in June or July, when the sun is always up. Mech and his team were able to live very close to the wolves, see their dens, follow them on hunts. In writing up his work, he often found that there were experiences that didn’t belong in his scientific publications but which still seemed important, like they were teaching him something. “I had a pup come and untie my bootlace,” he told me. “I had an adult come up and sniff my glove. It was that close.” He was able to visit dens of cubs while the parents were away hunting, “though they usually left a babysitter, an older sibling, with the cubs.” Mech says that it was while he was on Ellesmere that “it dawned on me the need to tell the world about this alpha stuff. Because it’s nonsense. It makes no sense up here.”
The Schenkel study that gave rise to the terminology began in 1934, looking at wolves living at the Basel Zoological Garden. The conditions, as described in the study, were rough: “Up to ten wolves were kept together in a small area with a floor space of approximately 10 metres by 20 meters.” Not only were the wolves in captivity but they had been brought in from different zoos, and were unrelated to one another. This might be the equivalent of studying the human family by observing the culture of prisoners in a holding cell. Schenkel noted that “this space as a whole was regularly defended against the zookeeper by the whole pack.”
The story of Romulus and Remus, the founders of Rome, who were suckled by a she-wolf, hinges on the Latin term “lupa”—which at the time was used to refer both to a she-wolf and to a prostitute. European wolf myths often have this quality, of the wolf and the human as being in some ways the same. The figure of the wolf, in tales, has often been related to want and to struggle. In the Middle Ages, periods of famine were referred to as “the wolf.” Landlords sometimes earned the name, too. The wolf was a creature that threatened humans’ well-being. Highwaymen, for example, were said to come back as wolves. Wolves were the creatures, lurking in the shadows outside town, who might waylay or harm us. Or cure us. The wolf also appears in the names of the plants found in the storied woods: wolf’s milk, wolf apple, wolf’s thistle, and the small, poisonous purple-flowered wolfsbane. Wolf teeth were considered a panacea for teething; powdered wolf liver eased birth pains. Wolf skin would keep your shins from getting sore. That the wolves were viewed perhaps unfairly also comes through in lore. One folktale tells of a wolf seeing a group of shepherds enjoying a meal of mutton; the wolf complains that if he behaved as the shepherds did—eating a lamb!—he would be attacked with sticks and stones.
The Ojibwe people, a North American Indigenous group, say that the wolf was given to the first human as a companion. They see wolves as mentors to humans, modelling how to behave in a social group, and how to behave while hunting. Among the Pawnee, wolves are revered. In their belief system, the first death in our world was that of a wolf killed by humans—and this was what brought mortality to a previously immortal world. The Inuit have a giant wolf spirit named Amarok; he attacks hunters foolish enough to go out on their own at night. Wolves hunt in packs, and Amarok rewards the humans who do so, too.
If the idea of dominance through aggression doesn’t accurately illuminate wolf leadership, then what might? Which wolves are more likely to set off on their own (a process known as dispersal), find a mate, and start their own pack? Wolves are complex animals, with complex societies, but a recent finding shows how one factor is eerily simple, or at least well-defined—and affects humans, too. In a study published in Nature last November Kira Cassidy collaborated with Connor Meyer, as lead authors, on a project looking at the effects of infection by the toxoplasmosis pathogen in wolves. “In the back of my head somewhere, I remembered learning about toxoplasmosis in undergrad, just the basics, like, that it makes rats do weird things and get killed by cats,” Meyer told me. Meyer is a doctoral student in wildlife biology at the University of Montana. The idea that an infection could have an effect on behavior had stayed with him. (Toxoplasmosis infection has also been studied in humans, and some studies suggest that toxoplasmosis makes humans more aggressive, or more likely to get into a car crash or a motorcycle crash.)
The wolves in Yellowstone were introduced to the park in 1995, and have been studied continuously. “That means we have twenty-seven years of serology,” meaning blood samples, Meyer said. One of Meyer’s colleagues, Ellen Brandell, had done her Ph.D. on wolf diseases; she had sent more than a hundred samples of blood to be tested for toxoplasmosis, and knew that it was present in the park.
Toxoplasma gondii is a single-celled parasite. In Yellowstone, it multiplies in the small intestine of cougars, comes out in their feces, and then is ingested by wolves. The researchers looked at how infection in a wolf affected its decision to disperse and its assumption of leadership roles. Toxoplasmosis proved to be a strong predictor for both actions. “We were both pretty shocked not just by the results but by the strength of the results,” Cassidy said.
“It’s a fantastic paper,” Mech said of the work. (Cassidy was a master’s student under Mech.) I observed to him that, at first glance, the research almost gives one the impression that T. gondii is an amazing evil mastermind, affecting the behavior of these creatures that are so much more powerful than it—the cougar, the wolf—in order to serve its own ends; it was as if the parasite were the real alpha! “I know, it sounds so wild. But that’s just how evolution works,” he said with a smile. “That’s pretty fascinating, when you think about this parasite—it has no brains to be able to do this, and yet it appears to be driving the wolf to do its bidding.”
Mech said that he’d observed a similar parasite cycle on Isle Royale. This was a tiny tapeworm, about a quarter of an inch long: Echinococcus granulosus. “It lives in the gut of wolves, but, in order to complete its life cycle, the tapeworm’s offspring have to live in a hoofed animal”—such as a moose, a deer, or a caribou. The tapeworm lays its eggs in the gut of the wolf, which come out in the wolf feces and get into the water and on vegetation—which the moose, say, ingests. The parasite then makes its way into the moose’s lungs, where it lays eggs that reproduce asexually; eventually, the eggs together form a cyst. “Enough of those cysts form in the lungs of the moose—some cysts are as large as golf balls—and soon the moose can’t breathe as well as it once could.” Then come the wolves. “They eat the moose, and its lungs,” and the tapeworm makes it back to the wolf gut.
Cassidy and Meyer both noted that they had chosen their fields of study in large part in order to get to spend a lot of time outside. “I had thought as a kid that I would be a veterinarian, because I loved animals, especially dogs,” Cassidy said. “I grew up in Illinois, with no wolves, though we had coyotes, white-tailed deer, foxes.” She remembers learning, in the fifth grade, that wolves would be reintroduced to Yellowstone. “I felt sad, thinking, Why weren’t wolves already there?” (The U.S. government finished programmatically eradicating wolf packs in 1926; in 1978, it was proposed that they be returned; in 1995, the proposal began to be effected.) “Once I did make it out West, I really just fell in love with the mountains. I’m glad I came around to studying wildlife, and especially to studying a canid.” ♦
