{"id":39256,"date":"2013-03-08T11:07:46","date_gmt":"2013-03-08T16:07:46","guid":{"rendered":"http:\/\/planetsave.com\/?p=35095"},"modified":"2013-03-08T11:07:46","modified_gmt":"2013-03-08T16:07:46","slug":"three-hundred-year-old-mystery-of-the-falkland-islands-wolf-may-have-been-solved-by-geneticists","status":"publish","type":"post","link":"https:\/\/planetsave.com\/articles\/three-hundred-year-old-mystery-of-the-falkland-islands-wolf-may-have-been-solved-by-geneticists\/","title":{"rendered":"Three Hundred Year-Old Mystery of the Falkland Islands 'Wolf' May Have Been Solved by Geneticists"},"content":{"rendered":"
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The origin of the enigmatic Falkland Islands ‘wolf’ (FIW) — first observed by European explorers in the late 17th century — may have been determined at last by geneticists working from a fragment of a skull bone preserved by none other than Charles Darwin.<\/p>\n
The animal is actually a genus of canid called Dusicyon<\/em> (Dusicyon australis<\/i>). Previous analyses of museum specimens concluded that Dusicyon split from its nearest relative — the South American maned wolf (Chrysocyon brachyurus<\/i>) — around 7\u2009million years ago (Ma). It was formerly held that the FIW colonized the islands “by unknown means” approximately 330,000 years ago (ka).<\/p>\n Misnamed as a “wolf’, the canid was actually more closely related to foxes (genus: Vulpes<\/em>) than wolves (genus: Canis<\/a><\/em>). In fact, Darwin refers to the creature as a “wolf-like fox” in his journal. Unlike its ancient wolf cousins<\/a>, however, the canid — commonly called a warrah<\/em> — was known to be easily tamed and unusually friendly towards humans. It is this trait that most likely led to its extinction (i.e., its friendliness made it easier for explorers to kill it) over a hundred and twenty years ago.<\/p>\n But there are actually two mysteries here: the warrah’s evolutionary (phylogenetic) origin, and, its geographic origin on the islands<\/p>\n Dusicyon was the only terrestrial mammal known to have inhabited the islands. Owing to the Falkland Islands’ (also known as the Malvinas Islands) considerable distance (450 km, or about 300 miles) from the mainland of what is now Argentina, how<\/em> the canid came to be on the island in the first place has been a question that puzzled even Darwin when he visited the islands in 1834.<\/p>\n But thanks to some mutually supportive genetic and geologic sleuthing, these questions may have been answered.<\/p>\n Researchers (Cooper et al<\/em>) from the University of Adelaide conducted a genetic comparison between the island specimen (that Darwin bone fragment) and subfossil specimens from several of its mainland relatives (Dusicyon avus<\/i>). This comparison allowed researchers to determine the approximate date of newer segments of (mitochondrial) DNA found in the FIW specimen.<\/p>\n This dating in turn provided the main clue as to when the warrah became isolated from its mainland cousins. Dating analysis found that the warrah became isolated only 16 ka (averaged from a date range of 8 – 31 ka) — nowhere close to the previously presumed time frame of 330 ka. This time frame matches up very nicely with the last glacial phase (which ended around 11 to 12 ka)<\/p>\n <\/p>\n This dating also matched up with a fairly recent geological discovery; during this same period, a series of four submarine terraces had formed on the Argentine coastal shelf by low sea-stands. This suggests that Dusicyon’s earliest ancestors came to the islands via a narrow, shallow marine strait — most likely while it was frozen over.<\/p>\n “The Eureka moment was finding evidence of submarine terraces off the coast of Argentina,” said Cooper in a press statement, which he says would have formed around the time of the last glacial maxima (between 25,000 and 18,000 years ago). “At that time, there was a shallow and narrow (around 20km) strait between the islands and the mainland, allowing the Falkland Islands wolf to cross when the sea was frozen over, probably while pursuing marine prey like seals or penguins.”<\/p>\n As to why it was the only mammal ever found on the islands…The scientists believe that the journey across the strait was too treacherous for smaller mammals. However, this is not certain. Smaller mammals may have made it also, but it may have been that the warrah over-hunted all of the smaller mammals that had co-colonized the islands during the last glacial period. The canid may have consequently turned scavenger and\/or found other food sources, such as seals, penguins, other nesting birds, reptiles and\/or fish.<\/p>\n Over the three centuries since its first encounter with people, various waves of explorers had noted its docile, unusually friendly demeanor. The name Dusicyon,<\/em> in Latin means “foolish dog”.<\/p>\n Results of the research were published on 5 March 2013 in the journal\u00a0 Nature Communications<\/em>, under the title: ‘The origins of the enigmatic Falkland Islands wolf’<\/a>; authors: Jeremy J. Austin,Julien Soubrier,Francisco J. Prevosti,Luciano Prates,Valentina Trejo,Francisco Mena & Alan Cooper,\u00a0