Ground sloth

Illustration of living giant sloths in the Amazon by William Rebsamen.

Ancient rock art at Guaviare, Colombia, sometimes interpreted as a giant ground sloth.

Ground sloths, giant sloths, or giant ground sloths were a group of sloths belonging to four families (Megalonychidae, which also includes the extant two-toed sloths, Megatheriidae, Nothrotheriidae, and Mylodontidae; some authorities also consider Scelidotheriidae, Orophodontidae, and Rathymotheriidae distinct families) which lived in the Americas from the Eocene until at least 8,000 years ago, with an accepted later date of around 1550 years ago for the Caribbean species. They are generally considered to have been wiped out by human hunting.

Ever since the first ground sloth fossils were discovered in the late 18^th Century, it has been theorised that they may still persist in remote parts of the Americas, and a fairly large number of cryptids have been identified as possibly being ground sloths, if they are real. Cryptids which may be living ground sloths have been reported from Argentina, The Bahamas, Belize, Bolivia, Brazil, Canada, Chile, Colombia, Cuba, the Dominican Republic, Ecuador, Haiti, Mexico, Paraguay, Peru, Trinidad and Tobago, the United States, and Venezuela: as noted by Karl Shuker, "there is no doubt that a medium-sized species of surviving ground sloth would solve a number of currently unresolved cryptozoological conundra," and much larger, smaller, and even aquatic ground sloths have also been put forward as identities for certain cryptids.

Early European beliefs

When the first remains of Megatherium were discovered in 1788, they were believed to have belonged to a living animal, an enormous mole which had burrowed to the surface by accident, and been scorched to death by the sun. According to Bernard Heuvelmans, after the fossils had been studied and revealed as a giant sloth, the King of Spain instructed explorers to capture a live Megatherium for him.

When Thomas Jefferson described the giant sloth Megalonyx (which he believed to be a lion) in 1797, he assumed the animal was still extant, and asked Lewis and Clark, as they planned their famous expedition in 1804 to 1806, to keep an eye out for living specimens of Megalonyx, as this would support his case. Following the discovery that it was a sloth and not a lion, French naturalist Jean Baptiste Bory de Saint-Vincent agreed with Jefferson regarding its survival.

In 1848, British naturalist and antiquarian Colonel Charles Hamilton Smith theorised based on American Indian legends that the first people in the Americas had coexisted with giant ground sloths and mastodons - however, he did not believe that either animal was still alive.

Giant ground sloths

Patagonia

Although the first alleged evidence of modern-day ground sloth survival came from Patagonia, there have been few recorded sightings of ground sloth-like animals from the region. A collection of somewhat nebulous clawed monsters in Patagonian tradition have been connected with the Patagonian ground sloth, including the succarath, lobo-toro, and ellengassen. Florentino Ameghino also claimed that he had heard may stories of a:

“

...mysterious quadruped [...] in the interior of the territory of Santa Cruz, living in burrows hollowed out in the soil, and usually only coming out at night. According to the reports of the Indians, it is a strange creature, with long claws and a terrifying appearance, impossible to kill because it has a body impenetrable alike to firearms and missiles.

”

A statue of Mylodon at Puerto Natales, Chile, photographed by Wikipedia user Haplochromis.

Ameghino also wrote that Ramón Lista, governor of Santa Cruz, told himself, his brother Carlos Ameghino, and several other people of a sighting he'd had of a large, hairy, pangolin-like creature:

“

He came across it one day during one of his journeys in the interior of the territory of Santa Cruz , but in spite of all his efforts he was unable to cap- ture it. Several shots failed to stop the animal, which soon disappeared in the brushwood; all search for its recovery being useless. Lista retained a perfect recollection of the impression this encounter made upon him. According to him the animal was a a pangolin (Manis), almost the same as the Indian one, both in size and in general aspect, except that in place of scales, it showed the body to be covered with a reddish grey hair. He was sure that if it were not a pangolin, it was certainly an edentate nearly allied to it.

”

Hesketh Prichard, who was sent to Patagonia to search for the Mylodon, could not find a record of the encounter in any of the books written by Lista, who was dead by the time of the skin's discovery. Prichard did not believe a large animal could live in Patagonia's dense Valdivian forests, which he did not explore. However, he admitted that "in addition to the regions visited by our Expedition, there are, as I have said, hundreds and hundreds of square miles about, and on both sides of the Andes, still unpenetrated by man. A large portion of this country is forested, and it would be presumptuous to say that in some hidden valley far beyond the present ken of man some prehistoric animal may not still exist. Patagonia is, however, not only vast, but so full of natural difficulties".

Paraguay

During the second voyage of the HMS Beagle, Charles Darwin noted the South American belief that "there exists in Paraguay an animal larger than a bullock, & which goes by the name of "gran bestia", and wrote that, "if no credit is given to the actual existence of the "gran bestia", "then it must have been based on sightings of perfect Megatherium skeletons, as, according to him, the resemblance to a giant sloth is too striking to be accidental.

Both Darwin and Captain Fitz-Roy were told by a Bahia Blanca garrison commandant named Rodriguez that he had seen a gran bestia chained in Paraguay. It resembled a hog with talons (or "great claws"), and, although only a few months old, it already stood about four feet high. Fitz-Roy seemingly thought the animal could have been a yaquaru, a sabre-toothed cat-like animal, whilst Darwin believed it was simply a tapir.

Amazon Basin

Illustration of a giant ground sloth by Hermann Trappman.

Cryptids resembling cow-sized ground sloths have frequently been reported from the Amazon regions of Brazil, Peru, Ecuador, and Colombia. The most famous of these is the mapinguari, which is, however, also described as an ape-like animal. David Oren and the cryptozoologists of the Centre for Fortean Zoology, including Karl Shuker, believe the mapinguari may be a living ground sloth; older cryptozoologists such as Bernard Heuvelmans and Ivan T. Sanderson, as well as a number of modern cryptozoologists including Loren Coleman and Dale A. Drinnon, believe it is a giant hominid. Much of the confusion arises from mixed-up accounts of different animals, and the application of the name "mapinguari" to a number of different cryptids. Heuvelmans did associate a 21' long "human" footprint, supposedly made by the mapinguari, with either Megatherium or the Triassic Prestosuchus.

Traditional depiction of the mapinguari as a cyclopean humanoid compared to a giant ground sloth, drawn by Ray Troll.

According to Dale A. Drinnon, there have been consistent generic reports of creatures resembling bear-sized ground sloths from the Amazon since colonial times. Native accounts generally stress their large claws, which in more dramatic stories are said to be stained red with the blood of their victims. Drinnon refers to them as "wolfskins," and says that the old term su is still used to refer to them in parts of South America (see below). In 1953, explorer Leonard Clark claimed that a piece of Megatherium skin had recently been found in an "upland cave".

In 1997, anthropologist Glenn Shepard Jr. learned from some Peruvian Machiguenga people of the segamai, a cow-sized animal which can walk both quarupedally and bipedally, with dark matted fur and a snout "similar to" a giant anteater's. It is said to live in caves in the remote cloud and foothill forests, where it feeds on Cyclanthaceae plants and palm piths. The Machiguenga are terrified of it due to its reputedly aggressive behaviour, and it has a number of alleged characteristics in common with the mapinguari: it is said to be impervious to bullets, has a terrible roar, and supposedly generates an odour which stupefies or knocks out anyone who comes close to it. Shepard Jr. that it might be a bear: the Machiguenga, who knew spectacled bears (Tremarctos ornatus) well, "expressed great surprise and affirmed that the two animals are completely different". One of the tribe matter-of-factly told him that he had seen a segamai at Lima's Natural History Museum when he was a student, and when Shepard checked, he discovered that the museum had a diorama featuring a model of a giant ground sloth. However, the student had never seen the segamai himself, and had previously assumed it to be mythical.

The well-known theory that the mapinguari could be an extant ground sloth was first posited by David Oren, who has gathered more than a hundred claimed sightings during his time in Brazilian Amazonia. He initially regarded the mapinguari as a myth, but after speaking with a number of people in the Tapajós River basin who claimed to have seen it, Oren came to believe that the animal being described could only be a ground sloth.

In a 1993 paper for Goeldiana Zoologia, Oren demonstrated how each of the mapinguari's characteristics, as they were then known, were consistent with a human-sized mylodontid ground sloth. Almost all known hair samples from mummified ground sloths are reddish in colour. They are believed to have walked with their claws turned inwards, which would give rise to stories of backwards feet, as the unusual curvature would lead people to interpret the tracks the wrong way around, and fossil ground sloth tracks have been misinterpreted as giant human footprints, which they closely resemble in the past (Heuvelmans attributed backwards footprints in Asia to bears for similar reasons). Oren suggests that the more common, round track attributed to the mapinguari could be the imprint of the tip of its powerful tail. The fossilised faeces of ground sloths are almost identical to those of horses, just like the mapinguari. The mapinguari's reputed invulnerability could be explained twofold, by a mylodontids triple-layered bone ossicles covering the shoulders, back, and thighs, as well as the powerful, almost-fused ribcage present in some ground sloths — the combination of both characteristics would explain why only a shot to the navel or face can kill a mapinguari. Although ground sloths are famous for their great size, not all were so large, and since forest animals are frequently smaller than their open-environment cousins, it would make sense for a jungle ground sloth to be smaller. Oren's study of ground sloth hyoid bones suggested to him that they would have been capable of loud vocalisations, as indeed modern sloths are. Only the monkey-like face is inconsistent with what is known of ground sloths, but Oren suggested that some species could have had such faces, as the tree sloths do.

When Oren proposed a mylodontid identity, he had not spoken to anyone who claimed to have killed a specimen, and the hunters he spoke to afterwards did not mention the more fantastic traits, and gave details which both reinforced the ground sloth theory - including a head like a horse as opposed to a monkey, a slightly larger size and build, and hooked claws like those of an anteater - and suggested a slightly different familial identity, including four peg-like "canine teeth". Following the hunters' accounts, Oren modified his theory, suggesting that the mapinguari would be a megalonychid, not mylodontid, ground sloth: megalonychids, almost alone amongst the ground sloths, had frontal caniniform teeth (as did some specimens of mylodontids such as Glossotherium and Lestodon), and walked on the soles of their hind feet, so a sloth with "fangs" and a flat-footed locomotion could only be a megalonychid. Reconstructions of Megalonyx have twice been identified as the mapinguari by claimed eyewitnesses (Geovaldo and Salinas). Although megalonychids did not have ossicles like mylodontids, they still had very powerful ribcages. Additionally, some accounts ascribe the mapinguari's invulnerability to its hair, not any sort of armour—although the Karitiana kida harara, which is supposed to have fangs, is said to have "pebbles" under its skin. Oren also admitted that the hunters did not describe a ground sloth-like tail.

Theories related to ground sloths have also been put forward to explain some of the mapinguari's more fantastic characteristics. It was suggested that the abdomen mouth (which is not always described) could be a specialised scent gland which discharges a foul smell (which is almost always described) as a defense mechanism. Josh Gates, on the other hand, suggested that the description of a stomach mouth could be derived from people getting a bad look at a bipedal ground sloth holding its claws, which curve upwards, in front of its abdomen.

The kida harara of southwestern Brazil is often equated with the mapinguari. During Pat Spain's "animal identity parade" interview with kida harara eyewitness Geovaldo for Beast Man, the animals which he is shown (onscreen) to have no reaction to are an African elephant, a Bengal tiger, a spectacled bear, a white rhinoceros, and a gorilla. He showed no recognition of the spectacled bear, and thought the gorilla could be some sort of monkey. Geovaldo recognised the giant anteater and stated that the animal he had seen was "much, much different," with the only slight similarity being in the arms. When an image of the ground sloth Megalonyx was shown, Geovaldo unhesitatingly nodded and identified it as what he had seen, stating that "it was kind of like that. I think that was the animal. I really think that looks like it. Its arms were just like that." One difference he noted was that the claws on what he saw were similar, but even larger - other than that, it had the same body, the same arms, and the same face.

Illustration of an encounter with a living Megatherium by Zdeněk Burian, from the 1956 edition of the novel Plutonia.

Other, lesser-known Amazonian cryptids which may be ground sloths include the jucucu, which is also frequently lumped together with the mapinguari; the Orinoco giant sloth, which allegedly grows up to 5 metres (16 feet) long, and uses its large claws to browse from the tops of trees and dig up roots; and the ujea, the description of which reminded researcher Angel Morant Forés of a giant sloth. There are also dubious stories of a smaller, supposedly predatory ground sloth, called the xolchixe or "tiger sloth", from the Brazilian Amazon.

At least eight genera of ground sloths are known from the Pleistocene western Amazon, including two megatheriids, two megalonychids, and four mylodontids. There is no general consensus regarding the reason for their apparent extinction. Brad Rancy theorised that during the Pleistocene the region was cool, dry, wooded savannah, and that the expansion of the warm, wet rainforest wiped them out, leading Oren to suggest that a smallish species living in the gallery forests which existed at the time could have adapted to forest life. However, according to current beliefs, much of what is now the western Amazon was already tropical rainforest during the Late Pleistocene, with savannah to the south and east. Although no alleged sightings of ground sloths in the Amazon had been reported by the publication of Bernard Heuvelmans' On the Track of Unknown Animals (1955) - in which the examination of supposed living ground sloths focuses on the Patagonian ground sloth - Heuvelmans did predict that they might survive there. He noted that, since giant ground sloths were almost certainly wiped out by human hunting and not climate change, it is difficult to see why they would go extinct in regions uninhabited or sparsely inhabited by humans, particularly the tropical regions of northern South America. He concluded his examination of Patagonian ground sloths by writing:

“

Slaughtered by the nomadic hunting Indians, both in the pampas of the south and the green prairies of the north, the largest sloths would have retreated, as the jaguar did, to the tropical forests, where they could find a safer refuge. [...] it is not difficult to see how the medium-sized ground-sloths might have survived in wooded savannah or sparse forest, or even on the fringes of or in clearings in the densest of jungles. For the great ground-sloths were not destroyed by any revolutionary geological or climate change. From the number of their remains in kitchen middens it is clear that these large and peacable beasts, like so many other species, were victims of man's gluttony. If such is the case, what has happened to them in their impenetrable retreat in the vast Amazonian selva and the boscosa of the Andes, through which they passed in the course of ages? It is hard to see what, in the peace of these forests rarely inhabited by man, could have led to their extinction. Only human traps were able to put an end to these armoured brutes against which beasts of prey were powerless. Might they not still live in this 'green hell' and find it a heaven of peace?

”

Central America

Ivan T. Sanderson suspected that reports of cave cows from Belize, describing hairy lizard-shaped animals, referred to medium-sized living ground sloths.

United States

Illustration of a living Megalonyx in the United States by artist NocturnalSea on DeviantArt.

A handful of cryptids alleged to be living giant sloths have been sporadically reported from the United States, most notably the Appalachian ground sloth; the sheepsquatch, which is reported from a similar range, is also sometimes speculated to be a giant sloth. The Beasts of Sherman, allegedly sighted in New York in the 1960s, were explicitly identified as white giant sloths by the eyewitness, and the Beast of Boonville was said to have been a giant sloth captured in Mexico which had escaped captivity. Certain researchers also theorise that Bigfoot may be a living giant ground sloth.^{[primary source needed]}

Canada

The saytoechin, a large, hairy animal with claws reported from the Yukon, was identified with a picture of a giant ground sloth by Native American informants. These informants also reported that a saytoechin had been shot in a lake by a white man; this man's story, independently told by himself, described a sloth-like animal with a 3-foot-long tail. Ben S. Roesch suggests that, if it is a giant sloth, the saytoechin's purpoted predation of beavers is a misinterpretation, and that the animal really rips open beaver hives to eat the branches and vegetation they are made of.

Roesch also suggests that the giant squirrels of Nova Scotian Micmac lore were late-surviving ground sloths. Although they never harmed people, these animals were a nuisance to the Micmacs because they ate their houses, which were made of bark. According to the Micmacs, the giant squirrels eventually disappeared, but as the Micmac's legends are believed to occur no further back in history than around 500 B.C., the animals must have survived into medieval times in this area. Roesch also briefly speculated that the camel-like urchow of the Nass Valley could be another living ground sloth.

Small ground sloths

Illustration of the Puerto Rican sloth (Acratocnus odontrigonus), depicted without the long tail characteristic of ground sloths, by the American Museum of Natural History.

The smaller semi-arboreal ground sloths of the West Indies are believed to have gone extinct much later than the mainland sloths, perhaps persisting into the colonial era: according to Walker's Mammals of the World, their bones have been discovered in European middens alongside those of introduced domestic pigs. Yehos, small, ape-like creatures with claws (which are not a feature of primates) reported from Cuba, The Bahamas, Hispaniola, Trinidad, and Puerto Rico, may represent living or late-surviving forms of these smaller, arboreal West Indian ground sloths.

Missionary Thomas Bridges originally believed the saapaim, a shaggy, sheep-sized animal with large claws reported from the deepest forests of Tierra del Fuego in Chile, could have been "a sloth". Austin Whittall disagrees because of the saapaim's reportedly large and powerful incisor teeth.

Aquatic ground sloths

Reconstruction of Thalassocnus by Velizar Simeonovski.

At least two genera of giant sloth, the small freshwater Ahytherium of Brazil and the larger, marine Thalassocnus of Peru, were aquatic animals. Although they are believed to have gone extinct before the other giant sloths, around 3 million years ago, Austin Whittall speculates that a late-surviving (post-Ice Age) freshwater Patagonian species of the bulky Thalassocnus could explain several Patagonian lake monsters.

The ningen of the Antarctic Ocean, described as a 20' to 30' human-like being, has been connected with large marine sloths like Thalassocnus by some.^{[primary source needed]}

Ground sloth domestication

A report of an expedition within the Cueva Eberhardt leads some people to suggest that humans might have domesticated ground sloths. A summary of the report reads as follows:

“

It now appears that the remains of so-called Neomylodon are not found at the exposed entrance of the cavern, which is of very large proportions (30 metres high) , but occur only in an inner chamber which has every appearance of having been artificially constructed by cross-barriers. At a short distance from the entrance there is a rude wall of tumbled blocks extending the whole way across, except a narrow gangway left at one side. On passing through this the great chamber just mentioned is reached, and another wall-like barrier 50 metres further inwards extends completely across the cave from side to side, preventing any ingress except by scrambling. In the middle of the chamber there is an artificial mound. The floor proved to be covered with a layer of dust and stones, varying from 30 centimetres to a metre in thickness. In it at one spot were found numerous shells of mussels mingled with the broken bones of guanaco and deer evidently the remains of food of man. Beneath the surface layer near the inner barrier was discovered a great mass of excrement of a herbivorous animal, in some places more than a metre in depth. Most of the material was in the form of impalpable dust, which almost choked the workmen, but a few large lumps were in a good state of preservation, and rivalled the dropings of the elephant in size. Part of the heap showed clear indications of having been burned. Nearer the middle of the chamber was dug up considerable accumulation of dry cut hay in a good state of preservation. In the lower layer in the excrement, the hay, and the surrounding rubbish were found numerous broken bones of the so-called Neomylodon, belonging to several individuals, both old and young, with another well-preserved piece of skin.

”

See also

• Category:Theory: Living fossil - Ground sloth
• Carnivorous ground sloth theory
• Ground sloth domestication