Return of the extinct dire wolf? Not so fast…

Editor’s note: The author, Bob Zink, examines how modern science meets ancient legend – but has Colossal Biosciences really brought back an Ice-Age super-predator?

Darkness has fallen, and you’re about to climb down from your deer stand on a freezing November night. Suddenly out of nowhere you hear an eerie howl… close, in the direction of your truck.

Your gut tells you this is no normal coyote or wolf. You’d heard about these reintroduced “extinct” dire wolves with oversized teeth and jaws that can weigh up to 200 pounds. Twelve thousand years ago they ate horses, bison, and maybe mammoths. You wonder if this howl is one of those wolves.

Suddenly, given how far away the truck is, you wish you’d have brought more than your bow. And your second thought is: “Can dire wolves can climb trees?”

OK, dear readers, it is highly unlikely the above scenario could ever happen. At least I hope so.

As media reports shared extensively this week, a Texas-based company called Colossal Biosciences partnered with a high-profile scientist, Dr. Beth Shapiro, who’s into “ancient DNA” to reconstitute what they are calling a dire wolf, a species that disappeared from our landscape about 12,000 to 13,000 years ago.

At that time, much of the “megafauna” of North America disappeared, including saber-toothed cats, mammoths, giant ground sloths, camels, short-faced bears, and native horses, to name some.

Debate continues as to whether this die-off was a result of hunting and food-chain disruption by humans (the so called Pleistocene overkill hypothesis), or climate change that accompanied the end of the last Ice Age. I tend to lean towards the cause of the extinctions being a bit of both.

The process of creating a dire wolf was not trivial.

First, DNA was extracted from a 13,000-year-old tooth and a 72,000-year-old skull. This sounds easy, but it’s tricky because there’s very little DNA and it’s “degraded” so all the DNA that is harvested are just tiny bits. But these bits can be amplified and superimposed on each other to make a complete copy of the genome.

DNA is the genetic code that comes in just four letters, G, C, A, and T, and it’s the sequence of these letters that contains the blueprint for making an animal; DNA is the language of heredity. A super computer and AI look for areas of nonrandom overlap in these short sequences and determines how to line them up.

When aligned to each other, the gray wolf and dire wolf genomes were 99.5% similar. That sounds like an awful lot of similarity, like maybe a gray wolf is just a dire wolf. But if the genomes contain 2 billion bases, the 0.5% difference means that there are millions of bases that differ.

However, DNA is organized into genes, which make things, and there are only about 20,000 to 25,000 functional genes in this myriad of DNA bases.

The researchers settled on 15 genes that they thought were important differences between dire wolf and gray wolf, and then genetically engineered a gray wolf genome with these changes, put into a dog ovum in which the DNA was removed, and implanted it presumably in a gray wolf to develop.

Voila, three pups have been born, two males and one female. There are pictures of them all over the media as well as recordings of the young wolves howling. Whether this is what dire wolves sounded like is totally unknown – part of their allure is that they’re still puppies, and who doesn’t love puppies no matter what they do or sound like?

The newly engineered wolves exist in an undisclosed sanctuary where they’re looked after night and day. They were hand-reared, but some think they’ll learn to hunt. But given that they have no parents or pack members to learn from, and no natural prey, will whatever they do be indicative of what dire wolves were really like?

The many social media discussions of these dire-like wolves mostly focus on issues or problems, not the success of the breeding experiment. The first is what I just mentioned, that they are not 100% dire wolves, and hence, saying the dire wolf has been “de-extincted” is erroneous.

What we have is a genetically modified organism (GMO) that is a gray wolf with some, but not many, of the genetic tweaks that were in the genetic blueprint of dire wolf. One of my paleontologist colleagues remarked “making a GMO wolf larger and white doesn’t make it de-extinct.”

Second, the habitat in which they roamed, and the species they preyed upon, are long gone. So, there’s no way to envision their re-introduction into the wild, an idea called “re-wilding.”

We have enough issues with gray wolves, and a different species that is at least 25% larger would create only more problems. That said, they might kill off gray wolves, which replaced dire wolves after they disappeared.

Consider these newly reconstituted wolves: They’d be an issue, not just because they’d eat deer, but they don’t belong in the current ecosystem.

It wasn’t just the dire wolves and their prey that went extinct, but plant and insect communities also have changed. Our environment today is a totally different place than it was when dire wolves roamed the continent. Are we going to bring back the thousands of now-extinct plants and animals and create a veritable Pleistocene Park?

Because it hasn’t belonged to any ecosystem for 10,000-plus years, dire wolves might be considered an invasive species. Or maybe they’d be listed under the Endangered Species Act, or the Endangered de-Extincted Species Act?

I can’t begin to imagine what a poached dire-like wolf would bring on the black market. Speaking of invasive species, a colleague mentioned that the dire wolf is part of a South American radiation that “invaded” North America.

It matters then what you think de-extinction is, and according to Shapiro, how you define a species. If genetically engineering some genes from an extinct wolf into modern wolves creates something that looks different, which is her definition of a species, then de-extinction has been achieved.

If that’s the case, then a pug and a Dalmatian are unquestionably different species. Most professional biologists, myself included, do not think they have brought dire wolves back from extinction by any definition of species.

Authentic de-extinction would entail making an animal with an entire dire wolf genome, which has not been achieved, and that end-game appears a ways off. These new pups are a partial replica of a wolf-like animal that lived in a bygone era, and although we might long to know what a dire wolf looked like, we still don’t truly know.

Given that they can’t be released back into the wild, I see this accomplishment as more of a curiosity. However, the technology could be used to recover species that are on the brink of extinction like the red wolf, or species that became extinct more recently, like passenger pigeons.

Of course, like the dire wolf, the environment that supported a few billion passenger pigeons also is gone.

As a caution, it would be a unparalleled misuse of the science to suggest that we do not need to continue the Endangered Species Act because we can “de-extinct” species, because we cannot.

The scientific feat that Colossal and Dr. Shapiro accomplished is nothing short of amazing, but no, the dire wolf has not been de-extincted, it is still very much extinct.

Fortunately, the deer-stand scenario I envisioned at the start of this piece will only be in our (bad) dreams.

The author is a professor at the School of Natural Resources and School of Biological Sciences at the University of Nebraska-Lincoln, and curator of the Nebraska State Museum. He’s the former Breckenridge Chair of Ornithology at the University of Minnesota’s Bell Museum of Natural History.