When I woke up, the terrible wolf
Six hundred pounds of sin
Grinned at my window
All I said was “come in”
But don’t kill me, please
Please don’t murder me, don’t murder me
“Dark wolf”, grateful dead, Workers dead
The terrible wolf (Canis dirus), Prototype of the various wolves that were important members of the Stark family of characters game of Thrones, was found uniquely in North America until its extinction in the late Pleistocene (about 13,000 years ago). The relationship between this species and the native gray wolf (wolf), the coyote (Canis latrans) and the Asian wild dog or dhole (Cuon alpinus) is uncertain, however, as it is based solely on common morphological features. Perhaps this “lone wolf” trait and great size (~ 68 kg, despite artistic exaggeration) contributed to its iconic status in popular culture, which is as diverse as George RR Martin and the Grateful Dead, but “mythical” is not too exaggerated a popular culture description of this mighty beast.
Recently, a diverse and international group of researchers * has been studying the relationships between these North American species of canids, making both morphological features and genetic comparisons between modern wolves and death wolf fossils from both mitochondria and, to a limited extent, from genomic DNA (although focusing on comparisons of only one gene , COL1). Sites where the more than 700 terrestrial fossil wolves used in these studies were obtained (and associated academic facilities) were Natural Trap Cave, Wyoming (University of Kansas); Gigantobison Bay, Idaho (Idaho Museum Natural History); Sheridan Pit, Ohio (Cincinnati Museum Center); Guy Wilson Cave, Tennessee (University of Tennessee); American Falls Reservoir, Idaho (Idaho Museum Natural History); and Rancho La Brea Tar Seeps, Calif. (La Brea Tar Pits and Museum), the latter being the predominant site for the extraction of terrestrial wolf fossils (100 times more than gray wolf fossils from that site).
The paper begins by debunking (somewhat) the idea that dread wolves were “sister species” or conspecifics with gray wolves. Although the morphology of these species is very similar according to various comparison criteria, these authors examined 46 fossil direwolf specimens, dated between 12,900 and 50,000 years ago, for mitochondrial DNA (mtDNA) and, if less complex, for genomic DNA (which is much less well known) is). preserved). One of La Brea’s tar pit specimens yielded DNA from the type 1 collagen gene (COL1) of sufficient quality for comparison. These experiments suggested that dread wolves were not closely related to either gray wolves, coyotes, or African wolves (Canis Lupaster) or dogs (Canis familiaris). mtDNA analyzes supported these results that terror wolves formed a separate group that is evolutionarily very different from gray wolves and coyotes, as this phylogenetic tree illustrates:
In addition, these researchers analyzed nuclear genomic data from the dread wolves along with previously published genomic data from eight existing canids: gray wolf, coyote, African wolf, dhole, Ethiopian wolf (Canis simensis), African wild dog (Lycaon pictus), Andean fox (Lycalopex culpaeus) and gray fox (Urocyon cinereoargenteus– an outgroup). Only the gray wolves, coyotes, dholes, and gray foxes had geographical ranges that overlapped the dread wolf before its extinction during the Pleistocene. These analyzes confirmed what these scientists termed the “distant evolutionary relationship” between the dread wolf and other canid species. Further genomic comparisons indicated that the dread wolf was a branch of the canid line (the other two are African jackals and all other canid species), leading to the surprising result that gray wolves are more closely related to African wild dogs, Ethiopian wolves, and dholes than they are to terrible wolves.
Using these results to provide a “clock” to estimate when terror wolves deviated from other canid species, this article reports that terror wolves shared a common ancestor with other canid species approximately 5.7 million years ago (the estimate is in the range of 4 , 0-8.5 million years ago), with further deviation from African jackals about 5.1 million years ago (3.5-7.6 million years ago). Their genetic analyzes also showed no evidence of an extensive cross between dread wolves and other extant North American canid species. About 3 million years ago there was some evidence of genetic intermingling between ancestors of dread wolves and ancestors of gray wolves, coyotes, and dholes. These results are consistent with the ready-to-use genetic admixture that occurs among other things, between modern coyotes and gray wolves. In this context, the authors note that “our finding that no evidence of gene flow between dread wolves and gray wolves, coyotes, or their common ancestors was found – despite significant overlap with dread wolves in the late Pleistocene – suggests that the common ancestor of the gray wolves and coyotes likely evolved in geographical isolation from members of the dreadwolf lineage. “Given the evolution of other canid species and their status of immigration from Asia, these results suggest to these researchers that the dreadwolf originated in and with North America extinct Armbruster-Wolf could be related (Canis armbrusteri). Their genetic analyzes also suggest to these researchers that dread wolves are properly classified as their own separate genus. Aenocyon, an idea that was first proposed in 1918 (not for reasons of genetic comparison) (see Merriam, JC, 1918, Note on the Systematic Position of Wolves in the Canis dirus Group. Bull. Dept. Geol. Univ. California 10, 531-33). This genetic and geographic isolation of the direwolf from other canid species would explain the estimated age of the direwolf line and the evolutionary distance of this species from other canids.
The paper ends with speculation about why dread wolves became extinct at the end of the Pleistocene (linked to megafaunal extinctions, ie., the extinction of animals weighing more than 100 pounds such as the American lion, short-faced bear, mammoth, mastodon, ground sloth, and giant beaver) and other canids such as coyotes and gray wolves in North America, given “overall phenotypic similarities” between these animals. These speculations include greater morphological plasticity and dietary flexibility in canid species other than the direwolf or the ability to interbreed with other canids (which has been shown to allow for acquired traits such as coat color and improved immunity). The researchers suggest that the dread wolves’ inability to benefit from such phenotypic acquisition through interbreeding may have prevented them from resisting diseases transmitted by Old World taxa arriving across the Bering Land Bridge.
While the information is limited (e.g.., only five terrestrial wolf genomic DNA samples were intact enough to be examined), the results of these studies are another example of the power of genetic analysis to fill in the “voids” in the fossil record to identify animal (and Humans) in the Pleistocene, which led to population patterns of animals in the New World in the Holocene (today).
* Department of Archeology, Durham University, Durham, Great Britain; Australian Center for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia; Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA; School of Biological and Chemical Sciences, Queen Mary University of London, London, UK; Department of Archeology, Classics and Egyptology, University of Liverpool, Liverpool, UK; Faculty of Science and Psychology, Liverpool John Moores University, Liverpool, UK; The Palaeogenomics & Bio-Archeology Research Network, Archeology and Art History Research Laboratory, Oxford University, Oxford, UK; Department of Anatomy, Des Moines University, Des Moines, IA; Department of Zoology, Oxford University, Oxford, Great Britain; Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington, DC; Center of Excellence in Paleontology and Faculty of Earth Sciences, East Tennessee State University, Johnson City, TN; Department of Archeology, University of Exeter, Exeter, UK; Institute of Archeology, Russian Academy of Sciences, Moscow, Russia; ARAID Foundation, Instituto Universitario de Investigación en Ciencias Ambientales (IUCA) – Aragosaurus Group, Universidad de Zaragoza, Zaragoza, Spain; Department of Earth Sciences, Natural History Museum, London, UK; Evolutionary Genomics Section, The GLOBE Institute, University of Copenhagen, Copenhagen, Denmark; Applied Paleosciences, Bothell, WA; Department of Archeology, University of Sydney, Sydney, New South Wales, Australia; Department of Archeology, University of Aberdeen, Aberdeen, UK; Department of Archeology, Simon Fraser University, Burnaby, Canada; Institut des Sciences de l’Evolution – Montpellier, CNRS, Université de Montpellier, IRD, EPHE, Montpellier, France; Laboratoire Evolution & Diversité Biologique, UPS / CNRS / IRD, Université Paul Sabatier, Toulouse, France; Australian Museum Research Institute, Australian Museum, Sydney, New South Wales, Australia; Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA; Institute of Plant and Animal Ecology, Ural Branch of the Russian Academy of Sciences, Yekaterinburg, Russia; Ural Federal University, Yekaterinburg, Russia; Department of Anthropology, Texas A&M University, College Station, TX; Center for Evolution and Medicine, Arizona State University, Tempe, AZ; School of Human Evolution and Social Change, Arizona State University, Tempe, AZ; Halmos College of Arts and Sciences, Nova Southeastern University, Fort Lauderdale, FL; Department of Archeology, University of York, York, Great Britain; Institute for Systematics and Ecology of Animals, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia; Idaho Museum of Natural History, Idaho State University, Pocatello, ID; Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia; Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia; Tomsk State University, Tomsk, Russia; McDonald Institute for Archaeological Research, Cambridge University, Cambridge, UK; Greenland Institute for Natural Resources, Nuuk, Greenland; NTNU University Museum, Trondheim, Norway; Institute for Human Origins, Arizona State University, Tempe, AZ; Howard Hughes Medical Institute, University of California Santa Cruz, Santa Cruz, CA; South Australian Museum, Adelaide, South Australia, Australia; Palaeogenomics Group, Institute for Veterinary Sciences, Ludwig Maximilians University, Munich, Germany