Mylodon
Encyclopedia
Mylodon is an extinct genus
of giant ground sloth
that lived in the Patagonia
area of South America until roughly 10,000 years ago.
Mylodon weighed about 200 kilograms (440.9 lb) and stood up to 3 m (10 ft) tall when raised up on its hind legs. Preserved dung has shown it was a herbivore. It had very thick hide and had osteoderms within its skin for added armor. Because of this armor and its own long and sharp claws, it's unlikely Mylodon had any natural enemies other than humans, who would have still found the skin difficult to pierce with stone projectile point
s.
Mylodons close relatives include the giant ground sloths of the genera Glossotherium
and Paramylodon
. The latter genus has often been confused with Glossotherium but Paramylodon is a distinct genus that was restricted to the Pleistocene
of North America. Glossotherium also shares a long history of taxonomic confusion with Mylodon, and currently the only recognized species is Mylodon darwinii. At one time, the elephant-sized Megatherium
was thought to be closely related, but is recognized as belonging to a separate family (Megatheriidae
).
A variety of specimens found throughout Argentina
and Chile
indicate that Mylodon had a wide range of climatic and environmental tolerance. It was probably capable of inhabiting arid to semiarid and cold climates, humid and warm climates, and colder and montane climates.
on the basis of a nearly complete lower jaw with teeth, which was found by Charles Darwin
in a consolidated gravel cliff at Bahía Blanca
, during the survey expedition of HMS Beagle.
Well preserved samples of Mylodon remains have been discovered in the Cueva del Milodón site in Patagonia
, Chile
along the southern flank of Cerro Benítez
in the year 1896. Associated with bones of other early Patagonian animals, these remains of Mylodon date from an era earlier than 10,000 BC.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of giant ground sloth
Ground sloth
Ground sloths are a diverse group of extinct sloths, in the mammalian superorder Xenarthra. Their most recent survivors lived in the Antilles, where it has been proposed they may have survived until 1550 CE; however, the youngest AMS radiocarbon date reported is 4190 BP, calibrated to c. 4700 BP...
that lived in the Patagonia
Patagonia
Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...
area of South America until roughly 10,000 years ago.
Mylodon weighed about 200 kilograms (440.9 lb) and stood up to 3 m (10 ft) tall when raised up on its hind legs. Preserved dung has shown it was a herbivore. It had very thick hide and had osteoderms within its skin for added armor. Because of this armor and its own long and sharp claws, it's unlikely Mylodon had any natural enemies other than humans, who would have still found the skin difficult to pierce with stone projectile point
Projectile point
In archaeological terms, a projectile point is an object that was hafted to a projectile, such as a spear, dart, or arrow, or perhaps used as a knife....
s.
Mylodons close relatives include the giant ground sloths of the genera Glossotherium
Glossotherium
Glossotherium was a genus of ground sloth. It was a heavily built animal with a length of about snout to tail-tip, and could potentially assume a slight bipedal stance.Fossils of this animal have been found in South America...
and Paramylodon
Paramylodon
Paramylodon is an extinct genus of ground sloth of the family Mylodontidae endemic to North America during the Pliocene through Pleistocene epochs, living from around ~4.9 Mya—11,000 years ago .-Overview:...
. The latter genus has often been confused with Glossotherium but Paramylodon is a distinct genus that was restricted to the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
of North America. Glossotherium also shares a long history of taxonomic confusion with Mylodon, and currently the only recognized species is Mylodon darwinii. At one time, the elephant-sized Megatherium
Megatherium
Megatherium was a genus of elephant-sized ground sloths endemic to Central America and South America that lived from the Pliocene through Pleistocene existing approximately...
was thought to be closely related, but is recognized as belonging to a separate family (Megatheriidae
Megatheriidae
Megatheriidae is a family of extinct ground sloths that lived from approximately 23 mya—11,000 years ago, existing for approximately .Megatheriids appeared later in the Oligocene, some 30 million years ago, also in South America. The group includes the heavily-built Megatherium and Eremotherium...
).
Paleobiology
Mylodon has been traditionally considered a grazer in open areas, which is theorized based on its paleoenvironment as well as from the vegetation found in fossilized dung. However, recent studies based on biomechanics and functional morphology indicate that Mylodon may have been a mixed or selective-feeder instead, and the paleoenvironment of the formation where the animal was found indicates a wide variety of vegetation to be selected from.A variety of specimens found throughout Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
and Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
indicate that Mylodon had a wide range of climatic and environmental tolerance. It was probably capable of inhabiting arid to semiarid and cold climates, humid and warm climates, and colder and montane climates.
Condition of samples
At several sites preserved hide and dung have been discovered, and are in such a state of conservation that the people who first discovered them believed they belonged to a living animal instead of an extinct species. Mylodon was named by Richard OwenRichard Owen
Sir Richard Owen, FRS KCB was an English biologist, comparative anatomist and palaeontologist.Owen is probably best remembered today for coining the word Dinosauria and for his outspoken opposition to Charles Darwin's theory of evolution by natural selection...
on the basis of a nearly complete lower jaw with teeth, which was found by Charles Darwin
Charles Darwin
Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection.He published his theory...
in a consolidated gravel cliff at Bahía Blanca
Bahía Blanca
Bahía Blanca is a city located in the south-west of the province of Buenos Aires, Argentina, by the Atlantic Ocean, and seat of government of Bahía Blanca Partido. It has a population of 274,509 inhabitants according to the...
, during the survey expedition of HMS Beagle.
Well preserved samples of Mylodon remains have been discovered in the Cueva del Milodón site in Patagonia
Patagonia
Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...
, Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
along the southern flank of Cerro Benítez
Cerro Benitez
Cerro Benítez is a mountain in the Patagonian region of Chile. In a larger context this feature is an element of the Cerro Toro geological complex. The Cueva del Milodón Natural Monument is situated on the southern flank of Cerro Benítez. The Cerro Benítez is a location for sighting of the Andean...
in the year 1896. Associated with bones of other early Patagonian animals, these remains of Mylodon date from an era earlier than 10,000 BC.
Survival claims
The discovery of fresh looking samples of skin and dung sparked a small wave of expeditions during the early 20th century to search for a living example of the animal. The samples have since been found to be around 10,000 years old, although they look fresh because of the extreme cold and stable conditions in the caves in which they were found.External links
- www.sloth-world.org - Sloth World - an online bibliography