Shasta ground sloths in woodland

Giant ground sloths

Although related to modern tree sloths, giant ground sloths resembled no other animal: they lived on the ground, rivalled the mammoths in size and were some of the strangest mammals ever. Their remarkable claws were up to 50cm long, the size of a man’s forearm. Massive hind quarters gave way to much slimmer shoulders and a tiny head. Originally from South America - fossils have been found in Argentina - giant ground sloths spread north to the southern part of North America. Slight differences in fossils from South America suggest that males and females may have differed in size and/or appearance, which hints at a gender-based social structure.

Scientific name: Megatheriidae

Rank: Family

Common names:

great beast

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Additional data source: Animal Diversity Web

When they lived

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What their world was like

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Fossil types

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