The Japanese wolf (, , or , [see below]; Canis lupus hodophilax), also known as the Honshū wolf, is an extinct subspecies of the gray wolf that was once endemic to the islands of Honshū, Shikoku, and Kyūshū in the Japanese archipelago.
It was one of two subspecies that were once found in the Japanese archipelago, the other being the Hokkaido wolf. Genetic sequencing indicates that the Japanese wolf was highly divergent from living wolf populations.
Despite long being revered in Japan, the introduction of rabies and canine distemper to Japan led to the decimation of the population, and policies enacted during the Meiji Restoration led to the persecution and eventual extermination of the subspecies by the early 20th century. Well-documented observations of similar canids have been made throughout the 20th and 21st centuries, and have been suggested to be surviving Japanese wolves. Due to environmental and behavioral factors, though, doubts persist over their identity.
Etymology C. hodopylaxs binomial name derives from the Greek hodos (path) and phylax (guardian), in reference to Okuri-inu from Japanese folklore, which portrayed wolves or weasels as the protectors of travelers.
Numerous other aliases have referred to Japanese wolf, and the name ōkami (wolf) is derived from the Old Japanese öpö-kamï, meaning either "great-spirit"Kokugo Dai Jiten, Revised Edition 1988 (in Japanese), Tōkyō:Shogakukan where wild animals were associated with the mountain spirit Yama-no-kami in the Shinto religion, or "big dog",Kazue Nakamura, 2004, Japanese Names of the Animals Belonging to Genus Canis Described in "the Flora, Fauna and Crops of the Japan Islands" in the 18th Century., Bulletin of The Kanagawa Prefectural Museum Natural Science No. 34, pp.69-73, Kanagawa Prefectural Museum Natural or "big bite" (ōkami or ōkame),Miku Bansho, 2019, Why the oinu-sama' had not become extinct : A study on actual conditions of Musashi Mitake shrine, Research Journal of the Graduate School of Humanities and Human Sciences, Vol. 19, p.115, Faculty of Humanities and Human Sciences, Graduate School of Humanities and Human Sciences, and School of Humanities and Human Sciences, Hokkaido University and "big mouth"; Ōkuchi-no-Makami (Japanese) was an old and deified alias for Japanese wolf, where it was both worshipped and feared, and it meant "a true god with big-mouth" based on several theories; either referring to wolf's mouth with associations with several legends and folklore such as the wolf guided Yamato Takeru and was titled so by the prince, or a region in Asuka called Ōkuchi-no-Makami-no-Hara where Asuka no Kinunui no Konoha (Japanese) lived and a number of people were said to be killed by an old wolf there.Kichiro Akimoto, 1958, Fudoki Nihon Koten Bungaku Taikei 2 (Japanese), p.421, Iwanami Shoten
Taxonomy and origin
Nomenclature: "ōkami" and "yamainu" Before Dutch zoologist Coenraad Jacob Temminck classified it, it had been long recognized in Japan that Honshu was inhabited by two distinct canids, ōkami (wolf) and yamainu ("mountain dog", likely a type of feral dog), both of which were described by herbalist Ono Ranzan in his Honzō kōmoku keimō ("An instructional outline of natural studies") in 1803. He described the ōkami as an edible, but rapacious, greyish-brown animal with a long, ash-colored, white-tipped tail with webbed toes and triangular eyes that would occasionally threaten people if rabid or hungry. In contrast, the yamainu was described as a similar animal, but with speckled yellowish fur, unwebbed toes, a foul odor and inedible meat.
Ranzan's works were studied by German botanist Philipp Franz von Siebold during his tenure in Dejima. He purchased a female mountain dog and a wolf in 1826, describing both in his notes as distinct, and preparing two sketches illustrating their differences. The skin of the mountain dog was subsequently shipped to the Rijksmuseum van Natuurlijke Historie in the Netherlands and mounted. The specimen, along with Siebold's notes, were used by Temminck as references for his scientific classification of the animal in Fauna Japonica (1839). Temminck, however, misinterpreted Siebold's notes distinguishing the wolf and the mountain dog and treated the two as synonyms. In 1842, he wrote a longer description, still confounding the two names, and producing a sketch of a "wolf" based on Siebold's mounted mountain dog specimen.
Skeletal and genetic findings The Japanese wolf, or Honshū wolf, (Canis lupus hodophilax Temminck, 1893) is a subspecies of the gray wolf (Canis lupus). Skeletal remains of the Japanese wolf have been found in archaeological sites, such as Torihama shell mounds, dating from the Jōmon period (10,000 to 250 B.C).
The Japanese wolf inhabited Kyushu, Shikoku, and Honshu Islands but not Hokkaido Island. This indicates that its ancestor may have migrated from the Asian continent through the Korean Peninsula into Japan. The phylogenetic tree generated from its mitochondrial DNA sequences revealed a long branch that separated the Japanese wolf from other gray wolf populations and that it belongs to the ancient mDNA haplogroup 2 (represented today by the Italian wolf and scattered pockets of other wolves across Eurasia), while the Hokkaido wolf belongs to mDNA haplogroup 1 and this suggests that the Japanese wolf was the first arrival on the Japanese archipelago with the Hokkaido wolf arriving more recently from the north. The wolf was estimated to have arrived in Japan during the Late Pleistocene between 25,000 and 125,000 years ago, however a more recent study that looked at the past sea levels of the Korean Strait together with the timing of the Japanese wolf sequences indicated that it arrived to the southern islands less than 20,000 YBP. There have been several excavations of a large canid, which was comparable in size to North American dire wolf, dating the Late Pleistocene from Aomori and Shizuoka prefectures, however its relationship with either C. lupus hodophilax or C. lupus is unclear.Yoshikazu Hasegawa, Toshiyuki Kimura, Naoki Kohno, 2020, Late Pleistocene Megacanid (Mammalia, Canidae) from Yage Limestone Quarry, Central Honshu, Japan. (pdf), Bulletin of Gunma Museum of Natural History, 24, pp.1-13
See further: Evolution of the wolf – North America and Japan
An examination of sequences from 113 ancient Canis specimens from China and Russia did not match, which indicated that none of these specimens were the ancestors of the Japanese wolf.
Analyses of the mitochondrial DNA of 1576 dogs worldwide revealed that one Kishu and one Siberian Husky possessed the same haplotype as a Japanese wolf, indicating past cross-breeding. A more-refined study of Japanese wolf mitochondrial DNA showed that they could be further divided into two separate groups, and that the sequences from one Kishu, one Siberian Husky and one Shiba Inu could also be divided into the two groups. These dogs correspond to clade F of the mDNA phylogenetic tree among worldwide dogs, with clade F haplogroup dogs originating from a rare admixture between male dogs and more than one female ancestor of Japanese wolves, which have contributed to the dog gene pool.
In 2021, a genomic study found the Japanese wolf to descend from Pleistocene Siberian wolves and genetically distinct from living Eurasian wolves. The study found this lineage to occupy its own branch on the gray wolf family tree, with the modern gray wolf and most domestic dogs (aside from Native American dogs and some Asian breeds) being more closely related to each other than Siberian Pleistocene wolves. A 2022 study which sequenced the genome of a 35,000 year old wolf from Japan found that Holocene Japanese wolf represented the hybrid of separate migrations of wolves into Japan, one of Siberian Pleistocene wolves around 57-35,000 years ago, and later waves of mixed Pleistocene Siberian wolf and modern wolf ancestry around 37-14,000 years ago. A 2024 study found that Japanese wolves were nested within the diversity of living wolves as more closely related to (but not nested within) Eurasian wolves than to North American wolves, and that they were more closely related to domestic dogs than to other wolves, though Japanese wolves are unlikely to be the direct ancestors of domestic dogs. Contrary to the results of the 2021 and 2022 studies, no evidence was found for a close relationship with Siberian Pleistocene wolves and Holocene Japanese wolves (with the study finding that the 35,000 year old Japanese wolf more closely related to Pleistocene Siberian wolves than to Holocene Japanese wolves, contrary to the results of the 2022 study) which the authors suggested was likely the result of differences in statistical analysis.
Admixture with domestic and feral dogs had been common in Japan, and distinguishing the original wolf was already difficult as scientific approaches for classification and species identification only began in Meiji where authorities were troubled to distinguish damages by wolves and dogs. Intentional cross-breeding between wild wolves and female domestic dogs, being chained outside, to create strong breeds was common, and several "types" of "wolves" had been commonly recognized by publics including potential F1 hybrids. These aspects led Japanese researchers to indicate that hybridization was severe among wide ranges of the archipelago including Hokkaido, and may disrupt genetic and morphological studies to determine the true C. hodophilax and C. hattai.Mitsuru Minakata, 2021, Fielder, pp.43-47, vol.56, Kasakura Publishing Co,.Ltd.柚兎, 2017, 100年以上前に絶滅したニホンオオカミは、まだ生きているかもしれない？, Da Vinci, Retrieved on October 29, 2021Brett L. Walker, Kenji Hama, 2009, 絶滅した日本のオオカミ—その歴史と生態学, p.247, ISBN：978-4-8329-6718-2, Hokkaido University Press
Genetic analysis of Siebold's yamainu specimen using matrilineal mtDNA has found it to genetically match the Japanese wolf; however, its skull displays significant differences from other Japanese wolves. Due to this, it has been theorized that the yamainu may represent wolfdog hybrids between Japanese wolves and feral dogs, and Siebold's specimen was likely the offspring of a wolf mother and dog father.
Description