The link between dental microwear and feeding ecology in tree sloths and armadillos (mammalia: xenarthra)

摘要: The Xenarthra represents an enigmatic clade of placental mammals that includes living tree sloths, armadillos, and their extinct relatives, yet certain aspects the biology this group remains poorly understood. Here, we use scanning electron microscopy to test hypothesis orthodentine microwear patterns in extant xenarthrans are significantly different among dietary groups. In a blind analysis, were quantified at magnification 500× by two independent observers for species from four groups (carnivore–omnivores, folivores, frugivore–folivores, insectivores). Independent recovered same relative between-group differences patterns. Insectivores folivores have lower numbers scratches greater scar widths than frugivore–folivores carnivore–omnivores, neither able statistically distinguish insectivores nor differentiate carnivore–omnivores. Nevertheless, clear distinction exists between taxa trophic level habitat, which suggests reflects niche partitioning habitat more diet related forms. We suggest bite force chewing mechanics strong influence on formation microwear, may explain some observed overlap distinct (e.g. versus carnivore–omnivores). This study serves as positive step forwards our understanding ecological role xenarthrans, foundation using reconstruct palaeoecology ground glyptodonts, pampatheres. © 2012 Linnean Society London, Biological Journal Society, 2012, ••, ••–••.