When we think of sloths, we generally picture those famously sluggish, dog-sized, tree-dwelling beasts that spend much of their time hanging upside-down from branches in modern-day Central and South America. Millions of years ago, however, there were several additional, very different morphological types – of which the most famous and dramatic were the ground sloths.
Most of these were primarily terrestrial, some were rather bovine in appearance but with shaggy fur, and many were considerably larger than their arboreal relatives. Although principally quadrupedal, ground sloths were capable of squatting erect on their hind legs to browse upon high-level foliage, and their distribution range included not only tropical mainland Latin America, but also North America as well as various of the Caribbean islands.
There were four separate taxonomic families containing ground sloths. The largest species were the megatheriids, typified by Megatherium ('big beast') from the Pleistocene of Patagonia, which attained the size of an elephant (recently split from the megatheriids into their own taxonomic family are the nothrotheriids). At the other extreme were the megalonychids, some being the smallest of all ground sloths, but also including the ox-sized Megalonyx ('big claw'), which earned its name from the huge claw on the third toe of each of its hind feet. This latter family also contains today's two-toed tree sloths.
Intermediate in size between the above groups of ground sloth were the mylodontids - which are of particular cryptozoological interest. For although the last representatives of all types of ground sloth officially died out several millennia ago, reports of mysterious creatures resembling these supposedly bygone beasts have emerged from several different Neotropical locations in modern times - including in particular some compelling evidence to suggest that Brazil may harbour a species of living mylodontid, eluding scientific discovery yet well known to the native people sharing its secluded jungle domain, referring to this cryptid as the mapinguary.
Moreover, certain putative ground sloths living in modern times have been reported from localities outside the Neotropics, including the following pair of hitherto little-known examples.
THE SAYTOECHIN OR YUKON BEAVER EATER
In September 1989, the then recently-formed British Columbia Scientific Cryptozoology Club (BCSCC) was contacted by a Canadian First Nation member named Dawn Charlie concerning a mysterious beast featuring in their oral traditions relating to Yukon's wildlife. The beast in question was referred to as the saytoechin (which translates as 'beaver eater'), and was described as being bigger than even the biggest grizzly bear, and feeding principally upon beavers, which it apparently captured by flipping up their lodges and then seizing the exposed beavers inside. When Native Americans living in the area were shown a book of extinct mammals, they selected an illustration of a ground sloth as the saytoechin, and the most recent reported sighting of one dates from the mid-1980s. As documented in 1990 by BCSCC co-founder Prof. Paul LeBlond in #4 of the Club's newsletter after interviewing Dawn Charlie, the details given by her concerning this sighting are as follows:
The latest report was from Violet Johny, my husband’s sister, who was fishing with her husband and her mother at the head of Tatchun Lake 4 or 5 years ago. An animal came out of the woods, 8 or 9 feet high, bigger than a grizzly bear. It was a “saytoechin” and it was coming towards them. They panicked, fired a few shots over its head and finally managed to get the motor going and took off. There are other reports. There is also a report that a white man shot one in a small lake in that area. Beaver eaters are supposed to live in the mountainous area east of Frenchman Lake.
Although ground sloths are generally thought of as tropical Latin (particularly South) American creatures, before their official extinction at the end of the Pleistocene some species had migrated northwards and had indeed established themselves in parts of North America. At least five genera are currently represented by fossils discovered in various locations here, including a single species, Megaloynx jeffersonii, in Yukon.
Life-sized restoration of Megalonyx jeffersonii in life, at the Iowa Museum of Natural History (© Bill Whittaker/Wikipedia)
So in terms of zoogeography alone, a Yukon ground sloth is already known, but obviously a living one is another matter entirely – as is the saytoechin's apparent dietary proclivity for beavers. This is because according to traditional palaeontological belief, all forms of terrestrial non-aquatic ground sloth were exclusively herbivorous. Having said that: in 1996, Drs Richard Fariña and Ernesto Blanco from the Universidad de la República in Montevideo, Uruguay, published a thought-provoking if controversial paper in the Proceedings of the Royal Society, in which they proposed that Megatherium could have used its fearsome claws to overturn, stab, and kill glyptodonts as prey.
From analysing a Megatherium skeleton, Fariña and Blanco discovered that its olecranon (the elbow portion to which the triceps muscle attaches) was very short. This adaptation is found in carnivores, and optimises speed rather than strength. These researchers opined that this would have enabled Megatherium to use its claws like daggers, and they suggested that it may have commandeered kills made by the sabre-tooth Smilodon in order to add nutrients to its diet (such behaviour is known as kleptoparasitic). Moreover, based upon the estimated strength and mechanical advantage of its biceps, they proposed that Megatherium could have overturned adult glyptodonts as a means of scavenging or hunting them.
However, this proposal has not gained widespread acceptance. In particular, palaeontologist Dr Paul S. Martin considers it "fanciful", noting that in terms of their dentition, ground sloths lack the carnassials that characterise predators, and that to suggest even that they were scavengers (let alone predators) is a reach. In addition, ground sloth dung deposits studied by him in Arizona's Grand Canyon and also in caves in Nevada, New Mexico, and western Texas contained no traces of bone. So far, therefore, at least as far as the palaeontological world is concerned, the case for carnivorous ground sloths in the past (not to mention in the present) has yet to be convincingly made.
Exquisite vintage illustration of Megatherium, from Extinct Monsters - A Popular Account of Some of the Larger Forms of Ancient Animal Life, 4th ed., 1896, Reverend H.N. Hutchinson (public domain)
As for the saytoechin: as discussed by Canadian cryptozoologist Sebastian Wang in a BCSCC Newsletter article (fall 2006) documenting this little-known cryptid, although the Native Americans selected a ground sloth from a book of extinct mammals as resembling it there is little else that actually links the two creatures directly. Other, less dramatic identities for it include an unusually large grizzly bear or black bear, plus some cryptozoological ones, such as a bigfoot, or even a surviving short-faced bear Arctodus or giant beaver Castoroides, although the idea of a giant beaver habitually preying upon normal beavers does not seem very likely. As far as I am aware, no specific search has ever been made for the mystifying Yukon beaver eater, so it is surely time for someone to rectify this oversight.
GROUNDS SLOTHS ALIVE AND WELL AND LIVING IN NEW ZEALAND?!
It was cryptozoological archivist Richard Muirhead who kindly brought to my attention what must surely be the most unexpected claim ever made regarding alleged living ground sloths, which can be found in British retired submarine officer Gavin Menzies's book 1421: The Year China Discovered the World (2002). In it, he claims that from 1421 to 1423, during China's Ming dynasty under the Yongle Emperor, the fleets of Admiral Zheng He, commanded by the captains Zhou Wen, Zhou Man, Yang Qing, and Hong Bao, discovered the Northeast Passage, the Americas, Australia, New Zealand, and Antarctica; circumnavigated Greenland; attempted to reach the North and South Poles; and circumnavigated the world a century before before Ferdinand Magellan carried out the first officially-recognised circumnavigation. Not too surprisingly, mainstream historians do not agree with his claims, but such matters lie outside the scope of this present book of mine.
Megatherium statue in Bautzen, Germany (© Frank Vincentz/Wikipedia CC BY-SA 3.0 licence)
What does lie within its scope, however, is Menzies's suggestion in his own book that on one of their ships the Chinese took aboard some mylodontids captured in Patagonia but that upon reaching New Zealand in c.1421 a pair escaped when the ship was wrecked in Dusky Sound in Fjordland at the southwestern tip of South Island. Moreover, in 1831 a ship from Sydney, Australia, visited Dusky Sound, where two sailors from the ship saw an animal that according to Menzies fitted the description of a ground sloth.
If so, this would indicate that the escaped mylodontids from the 1400s had not only survived in New Zealand but must also have established a population that was still in existence there four centuries later – always assuming of course that the beast seen was indeed a ground sloth, which is a massive assumption to say the least, and even more so when an independent source of information concerning this latter cryptid is examined (see below). Also, the wrecked ship was not Chinese, but an English vessel called the Endeavour, and was wrecked in 1795, not 1421.
Further information concerning this very strange state of affairs was presented in Robyn Jenkin's fascinating book New Zealand Mysteries (1970), which contained the following detailed account of the sailors' mystery beast sighting:
Even more bizarre was a story, also reported to the Collector of Customs in Sydney when the Sydney Packet returned home in 1831. One of the ship's gangs which had been stationed at Dusky Sound told of the discovery of an enormous animal of the kangaroo species.
The men had been boating in a cove in some quiet part of the inlet where the rocks shelved from the water's edge up to the bushline. Looking up they saw a strange animal perching at the edge of the bush nibbling the foliage. It stood on its hind legs, the lower part of its body curving into a thick pointed tail, and when they took note of the height it reached against the trees, allowing five feet for the tail, they estimated it stood nearly thirty feet in height!
The men were to windward of the animal and were able to watch it feeding for some time before it spotted them. They watched it pull down a heavy branch with comparative ease, turn it over and tilt it up to reach the leaves it wanted. When it finally saw them, the animal stood watching the men for a short time, then made one almighty leap from the edge of the bush towards the water's edge. There it landed on all fours but immediately stood erect before making another great leap into the water. The men were able to measure the first jump and found it covered twenty yards. They watched the animal plough its way down the Sound at tremendous speed, its wake extending from one side of the Sound to the other.
Here again one is tempted to think the rum was talking, and for an Australian going away from home for months on end, what other animal would stir the imagination but a kangaroo? But how much more romantic to think that perhaps they really had seen some prehistoric animal living out its days in the remote fastnesses of the West Coast Sounds.
Romantic it may be, but the mundane reality is that no ground sloth is suspected to have behaved in the highly dramatic manner ascribed to the creature described above, or to have attained its colossal dimensions, which even dwarf those of the mighty Megatherium. In any case, as no comparable accounts appear to have been filed in this dual-island country since that one, it is surely safe to say that if a living ground sloth is indeed discovered one day, it will not be anywhere in New Zealand!
My late mother, Mary Shuker, alongside a life-sized Megatherium statue by Victorian sculptor Benjamin Waterhouse Hawkins in London's Crystal Palace Park, photographed in 2010 (© Dr Karl Shuker)
My sincere thanks to Sebastian Wang for making available to me his detailed BCSCC Newsletter article on the Yukon beaver eater, and to Richard Muirhead for bringing to my attention the remarkable history of New Zealand's alleged ground sloths.
This ShukerNature article is excerpted from my forthcoming book, Still In Search Of Prehistoric Survivors.