Mylodonts are generally considered to be grazers (graminivores) based on their high-crowned teeth with flat chewing surfaces, similar to those of modern grazers. However, the lack of enamel in the teeth of sloths makes comparisons difficult. The graminivorous diet was inferred based on the special tooth formation, analyses of the masticatory apparatus of Paramylodon showed that food was predominantly crushed in forward, backward, and lateral chewing movements, which is also indicated by corresponding grinding marks. This is not contradicted by the caniniform front teeth, which - if formed - are rather small. The mandibular joint is broadly developed in Paramylodon and has an unspecialized surface, the associated glenoid fossa on the skull appears shallow, which is typical of herbivores with their rotary chewing movements. However, an additional, nearly vertical articular facet occurs on the inner side, anchored in a depression on the outer wall of the wing bone. This tended to limit overly strong lateral masticatory movements. The arrangement of the Musculus masseter caused Paramylodon to open its mouth only 22°, which is considerably less than in two-toed sloths, which, however, have comparatively longer caniniform teeth. All in all, the structure of the masticatory apparatus rather suggests a preference for mixed plant diets.Virginia L. Naples: The feeding mechanism in the Pleistocene ground sloth, Glossotherium. Contributions in Science Los Angeles County Museum of Natural History 415, 1989, S. 1–23M. Susana Bargo und Sergio F. Vizcaíno: Paleobiology of Pleistocene ground sloths (Xenarthra, Tardigrada): biomechanics, morphogeometry and ecomorphology applied to the masticatory apparatus. Ameghiniana 45 (1), 2008, S. 175–196
