Extinct Ground Sloths (Paramylodon harlani, Nothrotheriops shastensis, and Megalonyx jeffersoni) Fact Sheet: Distribution & Habitat

Paleontologists use knowledge of the earth's rocks, global plate tectonic movements, ancient ecosystems, and the chemical process of fossilization to make sense of fossil distribution patterns and ancient habitats.

• Paramylodon: widely distributed across U.S., especially in western states (excluding the Colorado Plateau) (McDonald et al 2004)
• Nothrotheriops shastensis: primarily western U.S. but also in Florida, Texas, Mexico. (McDonald 1985)
• Megalonyx: wide distribution in over 150 sites in United States, including Alaska, northwestern Canada, Mexico
• Fossils of three taxonomic families of sloths were found at Rancho La Brea asphalt deposits in California.

• Paramylodon: Not found in dry habitats; preferred areas of open grass or parkland; perhaps associated with permanent water in rivers and lakes from sea level to 2,330 m (7,644 ft) (Spaulding et al 1983) (McDonald 2004)
• Nothrotheriops: Found in habitats that are deserts today and were drier in the Pleistocene. (McDonald et al 2004); open savanna scrub land with trees; deciduous forests. (Hoganson & McDonald 2007)
• Megalonyx: Occupied gallery forests along rivers or lakes (Hoganson & McDonald 2007)
  • One skeleton from Illinois found with fossil pollen representing a spruce forest transitional to a mixed hardwood forest. (Schubert et al 2004)

Hoganson & McDonald (2007)
McDonald (1985)
McDonald et al. (2004)
Schubert et al. (2004)
Spaulding et al. (1983)