I'm not sure exactly how new this information is, but it dates to 2021, at least, and if I just heard about it, chances are people who are even more casually interested in paleontology than I am haven't yet.
The history of the dog family, Canidae, is an interesting one. Like the camel family and the horse family, the dog family originates in the Americas before crossing the Berengian land bridge relatively late, and then becoming more well-known through specimens that developed in the Old World. In some cases, these Old World developments then crossed back into the New World and are better known as natives to the New World in this form that underwent Eurasian development first, like the horse and the wolf, for instance. The actual wolf, Canis lupus, is a rather late-appearing Eurasian development that later spread into the New World. While they were common to North America as the first Americans knew it, they are now rather more rare, having come between Americans and their domesticated animals like cattle and sheep, and been seen as competitors. (And Mexicans—let's not forget that they've made their wolf subspecies locally pretty much extinct, which we notably did not completely do. And it was the efforts of American conservationists who prompted the "save the Mexican lobo" movement.) Their range and numbers are now rather more restricted, obviously. In addition to this, they never seem to have moved south of central Mexico in the New World, however—the canid species of South America are somewhat diverse and divergent, while the northern canids are mostly fairly closely related species within the Canis genus: various species of wolves (gray wolf, eastern wolf, red wolf), the coyote. Among them were several extinct species, such as America's dire wolf (Canis dirus), Arbruster's wolf (Canis armbrusteri) which was seen as ancestral to the dire wolf, and China's Canis chihliensis, which may have been ancestral to both Arbruster's wolf and the gray wolf, making the gray wolf and the dire wolf sister lineages of sorts. (And, of course, the domestic dog and the Australian dingo are believed to be descended from domesticated wolves as well.) Closely related to these lineages are animals like the jackals, especially the golden jackal, and slightly more distantly, the African hunting dog and the Indian dhole.
All of these together make up a lineage of "wolf-like" dogs, which is believed to have originated in Africa and spread to the rest of Eurasia from there, and from Eurasia back into North America where, ironically, the greater dog family initially was from. This "wolf-like" lineage is contrasted with the "fox-like" lineage (which naturally enough, includes most of the foxes that we know of. Also with the more diverse South American lineages with it's bush dogs and maned wolves, and finally there a number of other animals that don't fit neatly into these three bigger lineages, like the raccoon dog of Japan, Africa's bat-eared fox, and curiously, the familiar American gray fox. That fourth group is a bit of a puzzler, though, and some recent cladograms integrate them in to one or more of the existing three monophyletic lineages. It does appear that at least a few of them may not pass muster as one of those lineages though (the gray fox being the most likely) and stand as an independent free agent of sorts.
If I can be permitted a paragraph or two of digression—and of course I can, because it's my blog—all of these three (or four) lineages belong to a greater lineage within the dog family that goes back ~34 million years to the early Oligocene. None of them left the Americas before ~7 million years ago. For much of that time, and they were kind of in the shadow of another dog-family lineage, the Borophagines, which are now extinct. These were various sized and quite diverse animals, and include the largest of the canine species—big, burly nearly bear-sized critters like Epicyon being among the most notable. They are sometimes called "bone-crushing" dogs because many of their species had hyena-like adaptations for better carcass utilization, i.e. very strong jaws and molars that would break bones and thus enable at least parts of the bones to be eaten and digested, especially the marrow. It's curious that this diverse and broad group of animals played the cursorial hunting role in the New World where the hyena-family played the same role in the Old World, and this niche protection was pretty well established prior to the Berengian land bridge formation. The first dogs to cross over were primitive fox and wolf-like creatures, not Borophagines, however, where they were able to develop into today's wolves, foxes and more before returning "home" to the Americas. The so-called "hunting hyena" was an example of fauna going the other way. While we think today of the dogs, especially the wolf-like lineage, as being very similar animals and wide-spread and successful, things were considerably different until quite recently; the dog family was much more diverse, with the remnants of a totally different lineage of canines still putting forth some of its best efforts as recently as the late Pliocene, in the form of Borophagus diversidens for example, and hyenas weren't limited to being an odd animal or two in Africa; they were a much more diverse and widespread group until the very end of the Ice Age. With the disappearance of the mammoth steppe ecosystem, the cave hyenas' population crashed and they finally went extinct shortly after the ice retreated and the boreal forests extended over much of what was mammoth steppe. This allowed the wolves to spread out from their formerly smaller forested homes and become more widespread across Eurasia. The cave hyenas successfully kept them from spreading until ecological change made their own numbers take a nose-dive. They may even have been successful at limiting the spread of paleolithic man for a time, although that's a bit more speculative.
None of these extinctions should be seen as anything other than the kind of cyclical bad luck that comes up from time to time, though. Neither the hyenas and the borophagines, although drastically limited in the case of the former or extinct in the case of the latter, were unsuccessful in any meaningful way. They corresponded morphologically very closely to each other in an interesting way, and even some members of the modern dog lineages have mimicked their body plan and morphology, specifically the dire wolf, which also had much larger and stronger jaws and teeth than today's wolf. If the hyenas and borophagines weren't successful, why is that body plan being imitated over and over again? Rather, what we see right now is a kind of "post apocalyptic" scenario, where only the most generalist animals among the cursorial hunters remain. The wolf-like lineage just isn't all that specialized, and we can assume that the way things are going, in a few million years they'd be imitating the hyena and borophagine adaptations again, because they're just that good. They just haven't done so yet because they're still the "early" generalist examples of their lineages. Anyway... tangent over.
Recent DNA evidence is tearing up our old morphological models of descent of the modern canines, however. We now believe that all of the African lineages diverged separately from the Eurasian lineages, for instance, and many of the African species have been "promoted" to sister species rather than subspecies or regional morphs. The entire wolf-like lineage is now seen to be likely rooted in Africa originally, where there's more diversity of the lineage even today. Although that's less important than the big news; while sequencing a few dire wolf samples from which DNA evidence was able to be extracted, it was discovered that the dire wolf's last common ancestor with the gray wolf was much older than we thought; in fact, the dire wolf is the most distantly related to all other wolf-like lineage animals. It is basically a sister-group to everyone else combined. That's the technical term; more flippantly yet also more accurately, it's the fifth or sixth cousin group; the one that's so distantly related you're not quite sure why they're even at the family reunion at all because they're right on the verge of being too distant to be invited. The dire wolf probably developed from Armbruster's wolf, but Armbruster's wolf did not likely develop from the Chinese Canis chihliensis at all, but was rather a completely and totally home-grown alternative that was native to the Americas and always was. All of this in spite of a morphologically very similar skeleton.
A side effect of this is that the restorations that we usually see where the dire wolf just looks like a little bit beefier wolf, are almost certainly wrong. The soft tissue model of the wolf; shape of the ears, fur, etc. should not be assumed to be a good model to use for the dire wolf, given that the dire wolf is not really all that closely related to the gray wolf after all. The African hunting dog is more closely related to the gray wolf than the dire wolf, and yet it has a completely different ear shape and pelage. The dire wolf was probably as divergent physically. This very recent artwork by the king of mammal age paleoart, Mauricio Anton takes this idea with a totally different take on how dire wolves might have looked. This piece shows two familiar-looking gray wolves getting into a bit of conflict with a pack of morphologically distinct dire wolves over the carcass of an Ice Age buffalo (Bison antiquus. Antique bison?) in the oak savanas of the late Pleistocene southern California that are probably now chaparral or even desert today. In fact, exactly that ecological change is what likely caused the dire wolf's downfall, opening up the possibility for the gray wolf to expand over the territory. Very similar to what happend in the Old World with the cave hyena.
Compare that to a piece he did a few years earlier below. The focus is really on the La Brea Smilodon's more than the dire wolves, but the dire wolves in the back chasing the "antique buffalos" are what you get when you assume that they are a closely related sister-group to the gray wolf; at a casual glance, you can't tell the difference between that interpretation of a dire wolf and an actual gray wolf. The image above is both more intriguing to fans of big animals as well as more much more likely based on this latest study.
According to this new paper, the dire wolf is no longer Canis dirus, because it's too divergent to fit into even the most generous definition of the genus Canis. An older name has been resurrected; Aenocyon dirus. This is similar to how genetic sequencing has suggested that the American lion was distinct enough to be a totally different species from the Old World lion after all, so it's now back to being Panthera atrox, although even more extreme; not only is the dire wolf a different species, but a completely different genus.
Two quick epilogue comments on this. The first one is a caution. Archaeogenetic or paleogenetic data is a quickly moving field, and you have to be a little bit careful about assuming that because a conclusion is made today that it will stand. In the human genome, until just about two years ago we were told, for instance, that the inhabitants of Great Britain (and its diaspora nations like Americans, Canadians, South Africans, Australians, New Zealanders, etc.) showed genetic continuity all the way back to the late Paleolithic, with only slight visibility of the Anglo-Saxon invasion and no visibility at all for the Roman, Viking and Norman invasions. This has been completely reversed by a few newer studies, where we're now saying that there was almost complete genetic replacement when the Neolithic farmers arrived on the isles and replaced the Mesolithic hunter-gatherers, and then an even more dramatic genetic turnover when the early Bronze Age Bell Beaker culture arrived. Celtic, Anglo-Saxon, Viking and more arrivals are now visible, at least in some areas. And even in the last few months, new papers have questioned some details of this new consensus already. We know quite a bit more about the human genome through history, or at least we think we do, than we do of wolves or other animals, and if we're seeing that kind of churn in our interpretation of human populations based on more data than we have for animal populations, then that should be a cautionary tale for our acceptance of interpretations of animal genetics. The interpretation could reverse again, or go a completely different and unexpected direction before it all settles down again. Not saying to be sceptical of this new interpretation; it is the best we've got right now, just saying don't be surprised if it changes again before it's done.
Secondly, for Dark•Heritage Mk. IV, I really wanted to have a Pleistocene megafauna to give the wilderness a somewhat more adventurous, wild, "safari" like vibe. I was careful to try not to get too deep into esoteric details that nobody would really notice; i.e., was there really any value in making a distinction between Camelus and Camelops, or Bison bison vs Bison antiquus, or various "horses" native to North America like the Hagerman horse, Scott's horse and the Yukon wild horse vs. Eurasian horses†? No, there's not. So, a horse is a horse is a horse, even if it's really as divergent from a horse as a zebra or a wild ass. A buffalo is a buffalo regardless of whether it's the modern buffalo vs the long-horned buffalo or the "antique buffalo" etc. But with the dire wolf, I wanted something different. I specifically wanted something that was a cursorial hunter, but bulkier, maybe meaner, more plains and savana dwelling rather than forest-dwelling, and something that was visually distinct enough to be readily differentiatable at a glance. Believing that the dire wolf was too wolf-like to play this role, I'd gone back to the Pliocene-Pleistocene boundary where the last borophagine dog went extinct and pulled them "forward." However, now I don't have to. With this new data, the dire wolf (or maybe I should call it the dire "wolf") is perfect for my "bone dog" role (short for bone-crushing dog, which I thought sounded too long for everyday usage.) Now, granted, does it really matter if I think in the back of my mind that the Dark•Heritage bone dogs are now Aenocyon dirus instead of Borophagus diversidens? It's not like anyone in the setting would make that distinction, which means that in terms of any and all description I use, it makes no difference at all either. It really only affects me personally, because I'm the only one who knows. The dire "wolf" might even have been capable of cracking bones, although probably not as well as Borophagus could. But somehow it makes it feel better. I've made less of a big deal out of that for DH5, but it's still a thing.
† I'm not actually convinced of the extinction of much of the megafauna as long ago as people say. There's tons of oral history about elephants on the northeast from the 1700s from guys who talked to Injuns and whatnot. I also think this paper makes a convincing argument that the Plains Indians horsemen had horses all along. The idea that they somehow developed this expert horse-centric culture only a generation or two after catching a few stray Spaniard horses is kind of absurd, if you really think about it.
http://curlyhorses.com/documents/AboriginalNorthAmericanHorse.pdf
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