From oral pathology to feeding ecology: the first dental calculus paleodiet study of a South American native megamammal

KAROLINY DE O. NASCIMENTO; LIDIANA ASEVEDO; MARCIA R. CALEGARI; GELFO J.N.; DIMILA MOTHÉ; LEONARDO DOS S. AVILLA

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2021

0895-9811

Macrauchenia patachonica Owen, 1838 is a native and extinct Quaternary mega mammal from South America. Although studies on macraucheniids started two centuries ago, when Darwin found the first fossils, M. patachonica paleobiology is still poorly understood. The dental calculus is an oral pathology that preserves in the fossil record and analysis of its content is a useful, simple, and low cost method to access paleobiological information of fossil mammals. Here, the paleodiet of an adult M. patachonica from Buenos Aires province, Argentina, was accessed using quantitative and qualitative analysis of dental calculus content. The sample was chemically processed and provided many phytoliths,  palynomorphs, sponge spike fragments, and diatom frustules. Both herbaceous phytolites (49%) and eudicotyledons (35.4%) were well represented. These results support, for this individual, a mixed feeding habit, including consumption of C3 and C4 plants composed oftree/shrub plants and C3/C4 grasses, although C3 could have been more significant. Dental calculus provided direct evidence of paleodiet elements of an extinct South American native mammal for the first time, and such data might support broader paleoecological, paleoenvironmental, and evolutionary studies.