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Dire Wolves Weren't Really "Wolves" At All But A Separate Lineage

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  • Dire Wolves Weren't Really "Wolves" At All But A Separate Lineage

    An international team consisting of 49 researchers across nine countries has made a surprising discovery concerning dire wolves (Aenocyon dirus) an extinct form of canine which inhabited the Americas during the Late Pleistocene and Early Holocene epochs (between 125,000 and 9500 years ago). They were a bit bigger than the largest modern gray wolf but possessed larger teeth and had a more powerful bite.

    Based upon morphological analysis they've largely been considered to be kind of like beefed up gray wolves but the new research, which for the first time sequenced their DNA, found that they were in fact more like distant cousins, far enough genetically different from other canine species that they likely couldn't have interbred, sort of like humans and chimpanzees. This may have limited their available gene pool and could have been a factor that led to their extinction.

    It looks like they arose in North America and split from existing canines approximately 5.7 million years ago and remained isolated long enough to become so genetically distinct, unlike wolves which arose in Eurasia and who frequently interbred with other species, such as dogs, coyotes and jackals.

    Source: Dire Wolves Were Not Really Wolves, New Genetic Clues Reveal


    The extinct giant canids were a remarkable example of convergent evolution

    Dire wolves are iconic beasts. Thousands of these extinct Pleistocene carnivores have been recovered from the La Brea Tar Pits in Los Angeles. And the massive canids have even received some time in the spotlight thanks to the television series Game of Thrones. But a new study of dire wolf genetics has startled paleontologists: it found that these animals were not wolves at all, but rather the last of a dog lineage that evolved in North America.

    Ever since they were first described in the 1850s, dire wolves have captured modern humans’ imagination. Their remains have been found throughout much of the Americas, from Idaho to Bolivia. The La Brea asphalt seeps famously document how prey animals mired in tar lured many of these ice age predators to a sticky death. The dire wolves’ tar-preserved remains reveal an imposing hunter up to six feet long, with skull and jaw adaptations to take down enormous, struggling megafauna. Though these canids had clearly evolved to handle the mastodons, horses, bison and other large herbivores then roaming the Americas, skeletal resemblances between dire wolves and the smaller gray wolves of today suggested a close kinship. It had long been assumed that dire wolves made themselves at home in North America before gray wolves followed them across the Bering Land Bridge from Eurasia. Now some well-preserved DNA seems to be fundamentally changing the story.

    The new study, published on Wednesday in Nature, began as an effort to understand dire wolves’ biological basics. “For me, it started with a decision to road-trip around the U.S. collecting dire wolf samples and see what we could get, since no one had managed to get DNA out of dire wolf samples at that point,” says Durham University archaeologist and study co-author Angela Perri. At the same time, geneticist and co-author Kieren Mitchell of the University of Adelaide in Australia was also trying to extract and study ancient DNA from dire wolf remains—as were other labs that eventually collaborated on the project.

    One of the researchers’ questions was how dire wolves were related to other wolves. For decades, paleontologists have remarked on how similar the bones of dire wolves and gray wolves are. Sometimes it is difficult to tell them apart. “My hunch was that dire wolves were possibly a specialized lineage or subspecies of gray wolf,” Mitchell says.

    But the new evidence told a different story. Preliminary genetic analyses indicated that dire and gray wolves were not close relatives. “I think I can speak for the whole group when I say the results were definitely a surprise,” Perri says.

    After sequencing five genomes from dire wolf fossils between 50,000 and 13,000 years old, the researchers found that the animals belonged to a much older lineage of dogs. Dire wolves, it now appeared, had evolved in the Americas and had no close kinship with the gray wolves from Eurasia; the last time gray wolves and dire wolves shared a common ancestor was about 5.7 million years ago. The strong resemblance between the two, the researchers say, is a case of convergent evolution, whereby different species develop similar adaptations—or even appearances—thanks to a similar way of life. Sometimes such convergence is only rough, such as both birds and bats evolving wings despite their differing anatomy. In the case of dire and gray wolves, lives of chasing large herbivores to catch some meat on the hoof resulted in two different canid lineages independently producing wolflike forms.

    “These results totally shake up the idea that dire wolves were just bigger cousins of gray wolves,” says Yukon paleontologist Grant Zazula, who was not involved in the new study. In fact, the similarity between the two has led gray wolves to be taken as proxies for dire wolf biology and behavior, from pack dynamics to the sound of the animal’s howls. The dire wolf’s new identity means that many previous assumptions—down to what it looked like in life—require reinvestigation. “The study of ancient DNA and proteins from fossil bones is rapidly rewriting the ice age and more recent history of North America’s mammals,” Zazula says.

    In technical terms, the new findings mean dire wolves may need a new genus name to indicate they are no longer be part of the genus Canis, to which gray wolves belong. Perri, Mitchell and their colleagues suggest Aenocyon, meaning “terrible wolf.” But the researchers don’t expect their findings to completely overturn tradition, and Aenocyon dirus would likely continue to be called the dire wolf. “They will just join the club of things like maned wolves that are called wolves but aren’t really,” Perri says.

    The new findings also add layers to experts’ ruminations on why dire wolves eventually disappeared as the last ice age closed. These predators became specialized in hunting camels, horses, bison and other herbivores in North America over millions of years. As those prey sources disappeared, so did the dire wolves. “In contrast to gray wolves, which are a model for adaptation,” Perri says, “dire wolves appear to be much less flexible to deal with changing environments and prey.”

    Nor did dire wolves leave a genetic legacy beyond the decaying DNA in their ancient bones. Although canids such as wolves and coyotes often create hybrids, dire wolves apparently did not do so with any other canids that remain alive today. Perri, Mitchell and their colleagues found no DNA evidence of interbreeding between dire wolves and gray wolves or coyotes. Dire wolves were genetically isolated from other canids, Mitchell notes, so “hybridization couldn’t provide a way out” because dire wolves were probably unable to produce viable offspring with the recently arrived wolves from Eurasia.

    By 13,000 years ago, dire wolves were facing extinction. Evolving in the harsh, variable environments of Eurasia may have given gray wolves an edge, Zazula notes, “while the big, bad dire wolves got caught off guard relaxing in southern California at the end of the ice age.” But what might sound like the end of the dire wolf’s story is really only the beginning. Preserved genes have shown that dire wolves and their ancestors were top dogs in the Americas for more than five million years—and the early chapters of their story are waiting to be rewritten.


    Source

    © Copyright Original Source



    The full paper, Dire wolves were the last of an ancient New World canid lineage can be read in PDF form at the hyperlink provided and here is the abstract:

    Abstract

    Dire wolves are considered to be one of the most common and widespread large carnivores in Pleistocene America, yet relatively little is known about their evolution or extinction. Here, to reconstruct the evolutionary history of dire wolves, we sequenced five genomes from sub-fossil remains dating from 13,000 to more than 50,000 years ago. Our results indicate that although they were similar morphologically to the extant grey wolf, dire wolves were a highly divergent lineage that split from living canids around 5.7 million years ago. In contrast to numerous examples of hybridization across Canidae, there is no evidence for gene flow between dire wolves and either North American grey wolves or coyotes. This suggests that dire wolves evolved in isolation from the Pleistocene ancestors of these species. Our results also support an early New World origin of dire wolves, while the ancestors of grey wolves, coyotes and dholes evolved in Eurasia and colonized North America only relatively recently.



    I'm always still in trouble again

    "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
    "Of course, human life begins at fertilization thatís not the argument." --Tassman

  • #2
    "the researchers found that the animals belonged to a much older lineage of dogs."

    I thought dogs descended from wolves?

    Comment


    • #3
      Originally posted by Sparko View Post
      "the researchers found that the animals belonged to a much older lineage of dogs."

      I thought dogs descended from wolves?
      That's always one of the problems with science stories in popular reporting. They tend to be rather sloppy.

      Further, nearly all of the reports in the news that I've read about this tend to say that dire wolves were exclusively in the Americas whereas in fact the remains of some have been found on the steppes of eastern Asia shortly after the above paper was submitted (A late Pleistocene fossil from Northeastern China is the first record of the dire wolf (Carnivora: Canis dirus) in Eurasia), where they would have faced very stiff competition from the apex predator in the region -- cave hyenas (Crocuta crocuta ultima)[1].

      So it looks like dire wolves did cross the Bering Land Bridge (a.k.a., Beringia) but not until they had already evolved enough to be genetically distinct from other canids






      1. their relationship to the modern spotted hyena has been a contentious one and recent DNA analysis is going a long way to solve that as well: Palaeoproteomic analysis of Pleistocene cave hyenas from east Asia

      I'm always still in trouble again

      "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
      "Of course, human life begins at fertilization thatís not the argument." --Tassman

      Comment


      • #4
        Originally posted by rogue06 View Post
        That's always one of the problems with science stories in popular reporting. They tend to be rather sloppy.

        Further, nearly all of the reports in the news that I've read about this tend to say that dire wolves were exclusively in the Americas whereas in fact the remains of some have been found on the steppes of eastern Asia shortly after the above paper was submitted (A late Pleistocene fossil from Northeastern China is the first record of the dire wolf (Carnivora: Canis dirus) in Eurasia), where they would have faced very stiff competition from the apex predator in the region -- cave hyenas (Crocuta crocuta ultima)[1].

        So it looks like dire wolves did cross the Bering Land Bridge (a.k.a., Beringia) but not until they had already evolved enough to be genetically distinct from other canids






        1. their relationship to the modern spotted hyena has been a contentious one and recent DNA analysis is going a long way to solve that as well: Palaeoproteomic analysis of Pleistocene cave hyenas from east Asia
        Thank you for the references!
        Glendower: I can call spirits from the vasty deep.
        Hotspur: Why, so can I, or so can any man;
        But will they come when you do call for them? Shakespeareís Henry IV, Part 1, Act III:

        go with the flow the river knows . . .

        Frank

        I do not know, therefore everything is in pencil.

        Comment


        • #5
          Originally posted by shunyadragon View Post

          Thank you for the references!
          I was delighted that Sparko asked the question he did which gave me the chance to bring up the one thing that troubled me about the paper and its reporting. Of course, as I noted the paper had been already submitted before the discovery of the remains in eastern Asia so it isn't their fault, but the news coverage of the publication of the paper could have been more thorough in that even I was aware of Asian dire wolves having been uncovered.

          I'm always still in trouble again

          "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
          "Of course, human life begins at fertilization thatís not the argument." --Tassman

          Comment


          • #6
            I am waiting for them to discover the remains of a Dire Chihuahua.

            Comment


            • #7
              Originally posted by Sparko View Post
              I am waiting for them to discover the remains of a Dire Chihuahua.
              I still think that there's a case to be made that they're not really dogs but descended from rabid rats.

              I'm always still in trouble again

              "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
              "Of course, human life begins at fertilization thatís not the argument." --Tassman

              Comment


              • #8
                Originally posted by rogue06 View Post
                I still think that there's a case to be made that they're not really dogs but descended from rabid rats.
                Dire rodents of unusual size then.

                Comment


                • #9
                  Originally posted by Sparko View Post

                  Dire rodents of unusual size then.
                  Points for the Princess Bride reference, but I think they've always been ankle biters.
                  Last edited by rogue06; 01-16-2021, 06:07 PM.

                  I'm always still in trouble again

                  "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
                  "Of course, human life begins at fertilization thatís not the argument." --Tassman

                  Comment


                  • #10
                    Originally posted by Sparko View Post
                    I am waiting for them to discover the remains of a Dire Chihuahua.
                    All Chihuahuas are dire Chihuahuas. Like Dachshunds, they have no idea that they are small. And while Dachshunds have the stuff to back up their swagger, Chihuahuas are really good at selling wolf tickets.

                    Comment


                    • #11
                      Originally posted by The Barbarian View Post
                      All Chihuahuas are dire Chihuahuas. Like Dachshunds, they have no idea that they are small. And while Dachshunds have the stuff to back up their swagger, Chihuahuas are really good at selling wolf tickets.
                      Dachshunds were originally breed to hunt badgers, who are known for their ferocity, especially when cornered. Their name in German literally means "badger hound"

                      I'm always still in trouble again

                      "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
                      "Of course, human life begins at fertilization thatís not the argument." --Tassman

                      Comment


                      • #12
                        Originally posted by rogue06 View Post
                        Dachshunds were originally breed to hunt badgers, who are known for their ferocity, especially when cornered. Their name in German literally means "badger hound"
                        Yep. Muscular, powerful jaws, and crazy brave. And their skin is so loose that a badger can seize them on the back of their neck and they can turn around and get him by the throat. And they can dig as well as any dog you can name.

                        That's what the job description calls for.

                        Comment


                        • #13
                          Originally posted by The Barbarian View Post

                          Yep. Muscular, powerful jaws, and crazy brave. And their skin is so loose that a badger can seize them on the back of their neck and they can turn around and get him by the throat. And they can dig as well as any dog you can name.

                          That's what the job description calls for.
                          I've always been wiling to give props to the old "weiner dog" They're also quite playful.

                          I'm always still in trouble again

                          "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
                          "Of course, human life begins at fertilization thatís not the argument." --Tassman

                          Comment


                          • #14
                            Originally posted by rogue06 View Post
                            I've always been wiling to give props to the old "weiner dog" They're also quite playful.
                            I'm fond of them. Had two. Loyal, playful, but not great with kids. They have a temper, and don't like being teased.

                            Comment


                            • #15
                              Originally posted by The Barbarian View Post

                              I'm fond of them. Had two. Loyal, playful, but not great with kids. They have a temper, and don't like being teased.
                              Never owned any and was around several when young -- but I was never one to "tease" dogs, unless in the most playful manner, so I never saw that side. With few exceptions dogs seem to really like me.

                              I'm always still in trouble again

                              "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
                              "Of course, human life begins at fertilization thatís not the argument." --Tassman

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