Millions of years ago, a variety of creatures lived in North America. The landscape was very different than the one we have today. Canidae, the biological family that includes dogs, wolves, foxes, and coyotes, emerged around 40 million years ago. Canidae, nicknamed canids, later diverged into three subfamilies, which include the earliest members of the gray wolf species Canis lupus.

Wolves and domesticated dogs are represented in art, literature, archaeology, and fossil evidence, suggesting they have lived in close proximity with people for thousands of years.

Today, gray wolves are found in North America, Eurasia, and even North Africa.

Prehistoric to Ancient times | Middle Ages to the Enlightenment | Nineteenth & Twentieth Centuries | Turn of the 21st Century

Date Event

40 to 15/10 million years ago (mya)

The most ancient group of canids was the Hesperocyoninae. This subfamily later gave rise to two other subfamilies, Borophaginae and Caninae, before eventually going extinct.

34 to 2 mya

There were around 66 species of Borophaginae. Scientists think some members of this subfamily were scavengers, since their jaws were so powerful they could crack bones of prey, much like modern-day hyenas. Some Borophaginae can be characterized as hypercarnivores, meaning they depended on meat for more than 70% of their diet, while others could have been hypocarnivores, eating much less meat.

34 mya to Present

Caninae were living in North America at the same time as their cousins Borophaginae. Some scientists think this group physically adapted to a changing environment when its front and hind toes became smaller and smaller over time until they completely lost any functionality. Losing those toes gave Caninae an advantage when the landscape in North America became more open and less forested—the toes were no longer needed for climbing trees.


Caninae is the only living subfamily of Caninae, and includes all wolves, foxes, coyotes, and dogs.

30 to 28 mya

There were around 25 species of canids living in North America.

10 mya

The canid family diverged into numerous species. The North American canids most like modern wolves appear in 10 million-year-old fossils.

6 to 4 mya

The climate started becoming cooler and cooler as glaciers began to spread. This initiated what scientists call an Ice Age, which set in about three million years later. This allowed some groups of Caninae to move into Europe, then Asia, through multiple migrations. A fox-sized member of the genus Eucyon lived among the larger canids and early members of this genus migrated from North America to what is now Eurasia and Africa where it began to develop into an early version of the modern-day gray wolf.

3 to 2.8 mya

The Isthmus of Panama formed, connecting the continents of North and South America. This allowed creatures on both continents to cross over and mingle in ways never possible before. Scientists call this the Great American Biotic Interchange.

3 million to 10,000 years ago

Early gray wolves coexisted with a creature called the dire wolf (Canis dirus), in both North and South America.


Scientists speculate there may have been two types of dire wolves, one that was smaller and one that was larger. These creatures had a more robust skull and smaller brain than their gray wolf cousins, and had larger upper slicing teeth. Scientists suspect dire wolves relied on slow-moving prey, such as giant glyptodonts (related to modern-day armadillos), ancient llamas, tapirs, and sloths. Reliance on slow-moving prey or inability to capture swifter prey native to open grasslands may have ultimately led to the demise of dire wolves. Dire wolves disappeared, along with a saber-toothed cat and some bear species, about 11,700 years ago.

400,000 years ago

Early people and wolves were living in close proximity with one another, long before people established settled communities and agriculture.



Throughout North America, wolves have acquired a mythic status, both feared and revered. This legendary position may have contributed to many communities’ fear and hatred of wolves. Though wolves rarely approach people, the eerie sound of their howling at night may have helped perpetuate their dark reputation. However, most historic and contemporary fear of wolves is rooted in their preying on livestock. Wolves threaten sheep, goats, and even cattle. Entire industries and species of dogs were developed to combat the economic threat posed by wolves.

Date Event


Native Americans lived with and hunted wolves long before European settlers arrived. Different native communities included wolves in their mythologies, depicted them as characters in stories, and integrated them into spiritual beliefs.


The Pawnee, for instance, recognized Sirius, the brightest star in the night sky, as the "Wolf Star." Its yearly pattern represented a celestial migration along the "Wolf Road" of the Milky Way.


Many colonists who established roots in New England had left European communities that encouraged wolf extermination. These European colonists brought their folklore and biblical references that color wolves as untrustworthy and dangerous.


Folktale: Full of symbolism and imagination, fairy tales such as “Little Red Riding Hood” and “The Boy who Cried Wolf” cast wolves as threatening villains.


Bible: “Beware of false prophets, who come to you in sheep's clothing but inwardly are ravenous wolves.” (Matthew 7:15, King James Version (1611))

1630 to 1645

New England colonies considered wolves pests and a danger to livestock, so they passed laws offering rewards (such as cash, wine, or other goods) to those who killed them.



Oral histories, published accounts, art, and literature were the most accessible sources of information about wild wolf populations in North America. Many of these accounts were provided by hunters, traders and travelers exploring the American West. The iconic American naturalist and illustrator John James Audubon hunted wolves and refers to them as cowardly, rapacious, ravenous beasts.

Date Event

1850 to 1880

The period before, during, and after the American Civil War is described by some as the era of the “Wolfers.” The term refers to wolf hunters who systematically killed wolves by by poisoning and baiting the wolves’ with favorite prey such as elk and bison.


The Homestead Act allowed settlers to move into areas that encompassed traditional wolf territories.


In less than one decade, some estimates suggest around 700,000 wolves were killed in the U.S.


Congress established Yellowstone National Park in the territories of Montana and Wyoming. The park included several wolf packs.


People moving into the American West killed off most native deer, elk, bison, and turkeys—wolf prey—as well as wolves.


Call of the Wild, by Jack London, was published. Buck, the hero of the novel, is a sled dog who ultimately heeds the “call of the wild” to join a wolf pack.


The U.S. government commissioned wolf hunters to remove wolves from public lands in the West. As part of this program, wolf extirpation began in Yellowstone National Park.


The last Yellowstone wolves were killed by commissioned government agents.


After wolves were killed off in Yellowstone, the elk population exploded. Park officials had to cull them by the thousands. Elk ate and destroyed trees that had been preventing erosion along streams, causing a decline in aquatic species and bird populations. Elk ate new sprouts, preventing new trees from growing. The coyote population increased, which caused a decrease in small mammals such as squirrels—driving out prey for foxes and raptors, among other species. In spite of ecological imbalance following the removal of wolves, the government continued to eradicate them for years to come.


During the Great Depression, the Walt Disney Company released the blockbuster cartoon The Three Little Pigs. In the story, the Big Bad Wolf threatens to destroy the hard work of the pigs. The wolf becomes a symbol of the economy, government, and threats to the working class.


The wolf archetype again hit the big screen when cinemas started showing what are now considered horror classics, such as Werewolf of London.


While some government agencies focused on removing wolf populations from federal lands, researchers collected useful data on the species. The most common scientific method for studying wild wolf populations was to track them by following a pack’s footprints in the snow or mud, and then measuring the length and width of paws, pace, and strides. Travel patterns such as walking in a single file-line were documented, with photographs and in handwritten notebooks.


The U.S. government claimed 24,132 wolves were killed by commissioned hunters.


The only remaining wolves in the lower 48 states of the U.S. were now found in part of Minnesota and Michigan.


Telemetry became standard for tracking wild animals, allowing scientists to get a better census of the wolf population. Telemetry involves using a hand-held antenna to find the very high frequency (VHF) transmissions from a transmitter placed in a collar that is attached to an animal. Scientists looking for the transmitter/animal find the signal in three different locations then triangulate the position.


This system is still in use today. Information about wild wolves is often collected by putting radio collars on a few representative individuals in the pack. To get a collar on a wolf, the animal must be trapped and sedated. Sometimes this is done in an actual cage trap, or with a foot trap that keeps the animal in place until the scientists can get to their location. Other times this is done by tranquilizing the animal using medicated darts. While the wolf is sedated, researchers only have a few minutes to take their temperature, measurements, blood tests, and any tissue samples for DNA testing. This information gives biologists an idea of how healthy the pack is, what they eat, and if there are diseases like Lyme disease. Once the collar is attached, researchers leave and the animal wakes up and re-joins the pack.


Learning more about pack activity, migration, and health began to give people a better understanding of wild wolves. This may have initiated a change in attitude that began to favor conservation over eradication.


A federal Endangered Species Preservation Act offered limited protection for wolves on federal lands.


In Europe, the Argos system was developed to monitor the environment and track highly mobile animals. The technology, still in use today, involves a device that sends signals to satellite receivers in polar orbits. The device, attached to the animal with glue, suction cups or bolts, allows researchers to capture acoustic information, daily GPS locations, and chemical information such as pesticide use. Some devices even include a digital camera.


The Endangered Species Act was established.


The gray wolf becomes federally protected in the lower 48 states and Mexico.


Ways of studying and tracking wild populations evolved as new technology was developed and GPS becomes more commercially viable.


The first known pair of wild Canadian wolves, dubbed the “magic pack,” moves into Glacier National Park, where wolves had previously been eradicated. A female wolf named Phyllis was outfitted with a radio collar and her movement followed by researchers. When signals were sent from the same place over a period of two weeks scientists assumed she was whelping (giving birth) and staying near a den. The “magic pack” reared five pups.


The U.S. Fish and Wildlife Service captured 66 Canadian wolves and released them in Yellowstone National Park and Central Idaho. This type of federal action spurred hope among those concerned with the conservation of the species. It also provoked fear, resentment, and even lawsuits among people concerned about their livestock and livelihoods.



Multiple lawsuits were filed by ranchers and environmental groups at odds with each other over the status of wolves. An unusually emotional and heated discourse erupts over the conservation of an animal. The significant amount of media attention, policies, laws, and public opinion surrounding this species is a testament to the iconic stature the species holds. The attention also reflects a broader discourse about predator management, animal-human conflict, and the value our society places on wilderness conservation.

Date Event

21st Century

An estimated 65,000 wolves live in North America, mostly concentrated in Canada and the U.S. state of Alaska.


The U.S. Fish and Wildlife Service continues to protect the Mexican gray wolf (Canis lupus baileyi), a struggling sub-species indigenous to the Southwest. The agency has proposed to remove the gray wolf from the list of threatened and endangered species. We encourage older students to further review the issues surrounding this species, and specifically to look at policies, laws and science—both proposed and in effect—in order to more fully grasp conservation status of this national icon.

    • "We reached the old wolf in time to watch a fierce green fire dying in her eyes. I realized then, and have known ever since, that there was something new to me in those eyes—something known only to her and to the mountain. I was young then, and full of trigger-itch; I thought that because fewer wolves meant more deer, that no wolves would mean hunters' paradise. But after seeing the green fire die, I sensed that neither the wolf nor the mountain agreed with such a view."
      —Aldo Leopold, A Sand County Almanac

    • Streptococcus bacteria are responsible for most tooth cavities and are a leading cause of oral infections.
    • "We have doomed the wolf not for what it is, but for what we deliberately and mistakenly perceive it to be—the mythologized epitome of a savage ruthless killer—which is, in reality, no more than a reflected image of ourself."
      —Farley Mowat, Never Cry Wolf

    • "Everyone knew there were wolves in the mountains, but they seldom came near the village—the modern wolves were the offspring of ancestors that had survived because they had learned that human meat had sharp edges."
      —Terry Pratchett, Equal Rites

    • "Getting a handle on why wolves do what they do has never been an easy proposition. Not only are there tremendous differences in both individual and pack personalities, but each displays a surprising range of behaviors depending on what's going on around them at any given time. No sooner will a young researcher think, 'That's it, I've finally got a handle on how wolves respond in a particular situation,' than they'll do something to prove him at least partially wrong. Those of us who've been in this business for very long have come to accept a professional life full of wrong turns and surprises. Clearly, this is an animal less likely to offer scientists irrefutable facts than to lure us on a long and crooked journey of constant learning."
      —Douglas W. Smith, Decade of the Wolf: Returning the Wild to Yellowstone

    • "A vast silence reigned over the land. The land itself was a desolation, lifeless, without movement, so lone and cold that the spirit of it was not even that of sadness. There was a hint in it of laughter, but of laughter more terrible than any sadness—a laughter that was mirthless as the smile of the Sphinx, a laughter cold as the frost and partaking of the grimness of infallibility. It was the masterful and incommunicable wisdom of eternity laughing at the futility of life and the effort of life. It was the Wild, the savage, frozen-hearted Northland Wild."
      —Jack London, The Call of the Wild

  • Term Part of Speech Definition Encyclopedic Entry
    animal migration Noun

    process where a community of animals leaves a habitat for part of the year or part of their lives, and moves to habitats that are more hospitable.

    controversy Noun

    disagreement or debate.

    culture Noun

    learned behavior of people, including their languages, belief systems, social structures, institutions, and material goods.

    endangered species Noun

    organism threatened with extinction.

    Encyclopedic Entry: endangered species
    Endangered Species Act Noun

    (1973) U.S. legislation that protects endangered species when they are threatened by human activity.

    evolution Noun

    change in heritable traits of a population over time.