The Coywolf Is Part Dog, Part Wolf, Part Coyote

Wolflike coyote standing in snow, looking at the camera — This eastern coyote is party coyote, part gray wolf, part domestic dog — and yet this hybrid is not a new species. Fiona M. Donnelly / Shutterstock

The coywolf sounds like something out of a science fiction, but it's just part coyote (Canis latrans), part gray wolf (Canis lupus) and part domestic dog (which is technically a subspecies of the wolf, Canis familiaris). The hybrid has popped up in Canada and the U.S. over the past century.

It's possible CoywolfFinalInPrint.pdf" title="http://www.easterncoyoteresearch.com/downloads/GeneticsOfEasternCoywolfFinalInPrint.pdf">they emerged when coyote populations entered Ontario as wolves were being extirpated from the Great Lakes region during the early 1900s, and they simply bred with the remaining wolves. Based on genetic analyses, they mated with dogs sometime in the mid-1900s.

Coywolves — since that's what we've decided to call them — seem to thrive in cities and suburbs just like genetically straight-forward Canis latrans.

However, they look a bit different from most coyotes and display some behavioral and physiological differences. They have a reputation for being a bit bold, can be more cooperative with each other, are stronger and larger-bodied and reach sexual maturity later.

Coywolves Aren't Like Other Hybrids

When is a species a species, and when is it not? It used to be we considered two animals the same species if they could mate and produce viable offspring (babies that could grow up to have their own babies). But despite being a hybrids, coywolves give birth to viable offspring.

On the contrary, a horse and a donkey are not the same species, even though they can produce offspring because the hybrid created by the two — the mule — is sterile. But sometimes hybrids are produced that are not sterile. What then?

Well, turns out making a new species takes a hot minute (hundreds of thousands — if not millions — of years, usually), so a fertile hybrid is still just a hybrid.

Why then, aren't coywolves sterile like mules? It turns out this whole species thing isn't as black-and-white as we've always believed.

Genetics

Because all dog species all have 76 chromosomes and coyotes and wolf genes only diverged from one another within the past 100,000 years or so, they are in the process of evolving away from each other, and can therefore still produce viable young.

Yet, when we look at a coywolf's genome, we can tease out what percentage is coyote and wolf and domestic dog. They're different, and yet not that different.

The percentage of each species in the genetic admixture present in any one coywolf differs depending on where it's found, yet they all seem to be a hybrid of the wolf, coyote and domestic dogs. (It's called a coydog if it has only coyote and dog DNA.)

Adaptation of the Eastern Coyote

According to one 2011 genetic study on a population of hybrid canid living in the eastern North America, the percentage of coyote DNA is between 60 and 84 percent, with between 8 and 25 percent wolf and around 10 percent dog.

The farther south and east you go, the percentage of wolf gets smaller and the percentage of dog increases. By the time you reach the Deep South, the coyote-wolf-dog percentage ratio is more like 91:4:5.

Another article published in 2015 using research conducted by North Carolina State University showed that basically all eastern coyotes in the country showed some degree of hybridization in their genetic makeup.

In short, anywhere that their populations overlapped with either eastern wolves or feral dogs, some interbreeding was bound to occur. "Pure coyotes" are now much rarer than what we would consider coyote-wolf hybrids.

Coywolves are not a unique species; it would take a lot longer than one century for that to happen.

It is interesting to scientists, however, to witness the hybridization in real-time — to watch the coyote-eastern wolf hybrids spreading over the landscape and to see how coyotes are taking the DNA of other dog species and using it to make them better at their job as top predators in human-centered landscapes.

Hybridization in Western Coyotes

Although the vast majority of research on coywolves has been conducted on eastern canid breeds, there is plenty of reason to believe that interbreeding has also occurred between the western coyote and nearby wolf populations.

A 2013 experiment conducted by the Northern Prairie Research Center artificially bred captive western gray wolves with western coyotes and found that the young produced were in good health, living long enough to reach sexual maturity and produce viable offspring of their own.

Since these two breeds encounter each other in the wild, it's likely that hybridization has also occurred without human intervention.