Falkland Islands Wolf[1] | |
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Illustration by John Gerrard Keulemans (1842-1912) | |
Conservation status | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Carnivora |
Family: | Canidae |
Genus: | †Dusicyon |
Species: | †D. australis |
Binomial name | |
†Dusicyon australis (Kerr, 1792) |
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Location of the Falkland Islands |
The Falkland Islands Wolf (Dusicyon australis), also known as the Warrah and occasionally as the Falkland Islands Dog, Falkland Islands Fox or Antarctic Wolf, was the only native land mammal of the Falkland Islands. This endemic canid became extinct in 1876 (on West Falkland island), the first known canid to have gone extinct in historical times. It was the only modern species in the genus Dusicyon. Original research supposed that the most closely related genus is Lycalopex, including the Culpeo and his domestic forms (perro fueguino, perro yagán), which itself has been introduced to the Falkland Islands in modern times. But 2009 research conducted by a scientific team directed by Graham J. Slater, a post-doctoral researcher at the University of California, Los Angeles, confirmed that the Falkland Island wolf's closest living relative is actually the Maned Wolf (Chrysocyon brachyurus) - an unusually long-legged, fox-like South American canid, which it separated from about 6.7 million years ago.[3] It was known from both West and East Falkland, but it is unknown if the varieties were much differentiated.
The fur of the Falkland Islands Wolf had a tawny colour. The tip of the tail was white. The diet is unknown. Due to the absence of native rodents on the Falklands, its diet probably consisted of ground-nesting birds such as geese and penguins, grubs and insects, as well as seashore scavenging.[4] It was sometimes said to have dwelt in burrows.
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The first recorded sighting was by Capt. John Strong in 1692.[5] Captain Strong took one of the animals on his ship, but during the voyage back to Europe the creature became frightened by the firing of the ship’s cannon and jumped overboard.[6] Louis Antoine de Bougainville, who established the first settlement in the Falkland Islands termed it a loup-renard ("fox-wolf"). The name "warrah" is simply a corruption of the term aguará (meaning "fox" in Guaraní[7], a Native American language ), because of its similarity with the Maned Wolf ("aguará guazú"). The warrah's Latin name translates into 'foolish dog of the south,' because of its apparent lack of fear of people.
When Charles Darwin visited the islands in 1833 he named the species Canis antarcticus and described it as common and tame. The settlers regarded the wolf as a threat to their sheep and organised poisoning and shooting on a massive scale. The absence of forests led to the speedy success of the extermination campaign. This was facilitated by the animal's tameness, as is common in insular species due to the absence of predators - trappers would lure the animal with a chunk of meat held in one hand, and kill it with a knife or stick held in the other. However, it would defend itself from humans occasionally if it needed to, as Admiral George Grey noted when they landed on West Falkland at Port Edgar (Falkland Islands) on December 17, 1836 -
A live wolf was taken to London Zoo, England in 1868, but survived only a few years.[8] In 1880, post-extinction, Thomas Huxley classified it as related to the Coyote. In 1914, Oldfield Thomas moved it into the genus Dusicyon, with the Culpeo and other South American foxes. (These other canids have since been removed to Lycalopex.)
Current researchers in 2009, also found that the four Falklands wolf samples that they examined shared a common ancestor at least 70,000 years ago, which suggests that they arrived on the Falkland islands before the end of the last ice age and before humans ever made it into the New World (Graham J. Slater et al. 2009[9]).
Darwin writing about his 1834 visit to the Falklands in his Journal and Remarks (The Voyage of the Beagle) has the following to say of Canis antarcticus -
The only quadruped native to the island, is a large wolf-like fox, which is common to both East and West Falkland. Have no doubt it is a peculiar species, and confined to this archipelago; because many sealers, Gauchos, and Indians, who have visited these islands, all maintain that no such animal is found in any part of South America. Molina, from a similarity in habits, thought this was the same with his "culpeu"; but I have seen both, and they are quite distinct. These wolves are well known, from Byron's account of their tameness and curiosity; which the sailors, who ran into the water to avoid them, mistook for fierceness. To this day their manners remain the same. They have been observed to enter a tent, and actually pull some meat from beneath the head of a sleeping seaman. The Gauchos, also, have frequently killed them in the evening, by holding out a piece of meat in one hand, and in the other a knife ready to stick them. As far as I am aware, there is no other instance in any part of the world, of so small a mass of broken land, distant from a continent, possessing so large a quadruped peculiar to itself. Their numbers have rapidly decreased; they are already banished from that half of the island which lies to the eastward of the neck of land between St. Salvador Bay and Berkeley Sound. Within a very few years after these islands shall have become regularly settled, in all probability this fox will be classed with the dodo, as an animal which has perished from the face of the earth. Mr. Lowe, an intelligent person who has long been acquainted with these islands, assured me, that all the foxes from the western island were smaller and of a redder colour than those from the eastern. In the four specimens which were brought to England in the Beagle there was some variation, but the difference with respect to the islands could not be perceived. At the same time the fact is far from improbable.[10]
When organising his notes on the last stage of the Beagle expedition, Darwin wrote of his growing suspicions that the Galápagos Islands mockingbirds and tortoises differed depending on which island they came from:
When I see these Islands in sight of each other, & possessed of but a scanty stock of animals, tenanted by these birds but slightly differing in structure & filling the same place in Nature, I must suspect they are only varieties. The only fact of a similar kind of which I am aware is the constant asserted difference between the wolf-like Fox of East & West Falkland Islds. If there is the slightest foundation for these remarks the zoology of Archipelagoes will be well worth examining; for such facts [would] undermine the stability of Species.[11]
The term "would" was added after the words had been written, suggesting a cautious qualification from his initial bold statement.[12] He later wrote that such facts “seemed to me to throw some light on the origin of species”.[13] It has been speculated that the unusual distribution of this animal (the only other canine species native to oceanic islands are the Island Fox of California, and Darwin's Fox of Chile - but these habitats are not as remote as the Falklands) and some details of the skull suggest that it originally arrived with natives visiting the islands and was kept by them as a pet in a semi-domesticated state. If that is true, the progenitor form from mainland South America would have become extinct during the last Ice Age. DNA analysis of museum specimens have proved rather inconclusive as to the exact relationship of this animal, some even suggesting hybridization (during the domestication process) with a relative or progenitor of the Coyote; it is not known whether this would have been biologically possible. Another possibility is that, during an Ice Age, a land bridge between Falkland Islands and South America enabled its ancestors to traverse the distance. At any rate, the Falkland Island Wolf is a biogeographical mystery.
According to a study published in 2009 in the journal Current Biology, the Falkland Islands Wolf's closest living relative is the South American Maned Wolf.[14] In the same study it is claimed that DNA evidence points to a common ancestor 6 million years ago. This is an interesting date, since canids didn't appear in South America until roughly 3 million years ago in a paleozoogeographical event called the Great American Biotic Interchange, in which the continents of North and South America were connected by the formation of the Isthmus of Panama. The lineages of the Maned Wolf and the Falkland Islands Wolf would thus have diverged already in North America. In any case the results of the study rule out the previous hypotheses of introduction by natives. An earlier study[15], published in 2003, on the brain anatomy of several canids placed the Maned Wolf and the Falkland Islands Wolf together, and with zorros of the genus Pseudalopex as well, on the ground of their unique morphology of the brain sulci and the prorean gyrus.
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