This is the "Summary" page of the "Extinct Ground Sloths (Paramylodon harlani, Nothrotheriops shastensis, and Megalonyx jeffersoni) Fact Sheet, 2009 " guide.
Alternate Page for Screenreader Users
Skip to Page Navigation
Skip to Page Content
sdzglibrarybanner San Diego Zoo Global Library

Extinct Ground Sloths (Paramylodon harlani, Nothrotheriops shastensis, and Megalonyx jeffersoni) Fact Sheet, 2009   Tags: extinct, fact sheet, fossil, mammal, san diego zoo, sdzg, sloth  

Extinct Ground Sloths (Paramylodon harlani, Nothrotheriops shastensis, and Megalonyx jeffersoni)
Last Updated: Jun 14, 2017 URL: http://ielc.libguides.com/sdzg/factsheets/extinctgroundsloths Print Guide RSS UpdatesEmail Alerts

Summary Print Page
  Search: 
 
 

Extinct Ground Sloths (Paramylodon harlani, Nothrotheriops shastensis, and Megalonyx jeffersoni)

Giant Ground Sloth 

Image credit: © San Diego Zoo Global. All rights reserved.

TaxonomyPhysical Characteristics

Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Pilosa (anteaters and sloths)

Family: Mylodontidae (family is extinct)

Genus: Paramylodon                              

Species: Paramylodon harlani

Family: Nothrotheriidae (family is extinct)

Genus: Nothrotheriops

Species: Nothrotheriops shastensis

Family: Megalonychidae (family has extinct and living/extant members)

Genus: Megalonyx (extinct)

Species: Megalonyx jeffersoni


Body Weight
Paramylodon harlani: varied estimates from 1,000 kg (2,205 lb) to 1,089 kg (2,400 lb)
Nothrotheriops shastensis: estimated 250 kg (551 lb)
Megalonyx jeffersoni: estimated near 1,000 kg (2,205 lb)

Body Length
Paramylodon harlani: 3 m (9.8 ft)
Nothrotheriops shastensis: about the size of a black bear
Megalonyx jeffersoni: 3 m (9.8 ft)

Pelage
Long hairs, especially on flanks and rear limbs.

Distribution & StatusBehavior & Ecology

Range
Paramylodon harlani: widely distributed across the U.S., especially in western states
Nothrotheriops shastensis: primarily western U.S. but also in Florida, Texas, Mexico
Megalonyx jeffersoni: wide distribution in over 150 sites in United States, including Alaska, northwestern Canada, Mexico

Habitat
Paramylodon harlani: preferred areas of open grass or parkland, perhaps near water; not found in dry areas
Nothrotheriops shastensis: areas that were drier during the Pleistocene—open savanna scrub land with trees; deciduous forests
Megalonyx jeffersoni: gallery forests along rivers or lakes

Status
All giant ground sloths are extinct. Causes unknown.

Locomotion
Studies suggest a range of movements, including tree-climbing, swimming, and burrowing.

Interspecies Interactions
Extinct ground sloths shared habitats with other large herbivores. Ex. Paramylodon harlani often found with mammoths in North America

Diet
Diets of ground sloths varied. Some exclusively herbivorous, some species also ate meat. See Diet & Feeding for details.

Predators
Ground sloths juveniles would have been vulnerable to the large cat predators (Smilodon, Homotherium, Panthera atrox) and perhaps Dire Wolves.

Reproduction & DevelopmentSpecies Highlights

Life stages
May have provided extended parental care. Had few young.

Feature Facts

  • The diversity of sloths in the fossil record is high; over 100 genera are recognized
  • 90% of sloth genera became extinct at the end of the Pleistocene
  • The adaptations and biology of living tree sloths are very different from extinct ground sloths; comparisions should be limited
  • Large powerful claws on the sloths' hands were probably for digging as well as defense.
  • Some ground sloths used caves as habitat
  • Sloths in the mylodontid family had small bony deposits (osteoderms) imbedded in their skin; other animals that have more developed osteoderms include lizards, crocodiles, and pangolins
 

About This Fact Sheet

© 2009 San Diego Zoo Global

How to cite: Extinct Ground Sloths (Paramylodon harlani, Nothrotheriops shastensis, and Megalonyx jeffersoni) Fact Sheet, 2009. c2009. San Diego (CA): San Diego Zoo Global; [accessed YYYY Mmm dd]. http://ielc.libguides.com/sdzg/factsheets/extinctgroundsloths
(note: replace YYYY Mmm dd with date accessed, e.g., 2015 Sep 10)

Disclaimer: Although San Diego Zoo Global makes every attempt to provide accurate information, some of the facts provided may become outdated or replaced by new research findings. Questions and comments may be addressed to library@sandiegozoo.org.

SDZG Library Links

Our Mission. The Library is dedicated to supporting San Diego Zoo Global’s mission by providing outstanding
information resources and research services to advance knowledge and strengthen our organization’s capacity to save
species worldwide. Our Vision. We will empower San Diego Zoo Global to lead the fight against extinction by serving as
the organization’s information hub and facilitating research of the highest quality.


© 2016 San Diego Zoo Global — All Rights Reserved

Our Family of Sites

  • Zoo logoSan Diego Zoo
  • Park logoSan Diego Zoo Safari Park
  • ICR logoSan Diego Zoo Institute for Conservation Research
  • SDZ Global logoSan Diego Zoo Global
Description

Loading  Loading...

Tip