What it is
Megatherium americanum was a giant ground sloth of the South American Pleistocene, standing taller than a person when rearing and weighing several tonnes. It is extinct. It browsed and grazed; it was not a tree sloth.
Range
Temperate South America, especially the Pampas and neighbouring regions of Argentina and Uruguay.
What happened
The species disappeared near the Pleistocene-Holocene boundary. At Campo Laborde, Argentina, bones with cut marks date to about 12,600 calendar years ago (Politis and later redating): direct evidence that people butchered Megatherium. Climate was also shifting. The American megafaunal pulse is the loss of large-mammal genera after first human arrival, not a wipeout of all fauna.
When / status
Extinct around 12,000-10,000 years ago; hunted in the late Pleistocene.
Human role
Hunting is archaeologically attested. Climate change is a co-cause in the wider South American extinction pulse.
Sources
Campo Laborde butchery dates (Politis et al.); reviews of South American megafauna extinction.