Phytolith analysis on dental calculus, enamel surface, and burial soil: Information about diet and paleoenvironment

Abstract

Silica phytoliths (microscopic remains originating in plant tissues) have been identified on the enamel surface and dental calculus of a sample of teeth selected from well preserved skeletons from a Late Roman necropolis in Tarragona (Spain). Phytoliths were observed by scanning electron microscopy (SEM) and their siliceous nature was confirmed by X-ray microanalysis. The phytoliths were compared to those of soil samples from both the areas of the tombs corresponding to the abdomen and the periphery of the skeletons, and were classified taxonomically by comparison with a large collection of silica particles from modern plants in the Mediterranean area. Most of the phytoliths identified on the enamel and the dental calculus belong to the family of Poaceae, while the phytoliths from the abdominal area belong to Poaceae, Leguminosae, Cyperaceae, and Chenopodiaceae. Results are concordant with archaeological, ecological, and historical data from the same site, and with the human Mediterranean diet. If done properly, the study of phytoliths can provide direct information about the vegetable diet of past human populations, and could be applied to the study of human fossils.

Dental wash: a problematic method for extracting microfossils from teeth

“…In addition, microfossil studies on lithic instruments (Piperno and Holst, 1998;Piperno et al, 2000;Barton et al, 1998) reported much lower concentrations of starch than we found in the human teeth. Besides that, the number of phytoliths found in both our teeth samples was lower than that observed in samples from individuals of the late Roman period (Fox et al, 1996), in teeth of an extinct ape (Ciochon et al, 1990) and in herbivore teeth (Middleton and Rovner, 1994). The concentrations of phytoliths in our samples were also very small when compared to that of the starch grains of these same teeth.…”

“…Until now, researchers detached thick dental deposits from archaeological human teeth for analysis (Fox et al, 1996;Reinhard et al, 2001a,b). Dental calculus consists of microfossils, including a variety of phytoliths (silica or calcium oxalate bodies) and starch grains, trapped into the carbonate calculus matrix (Fox et al, 1996).…”

“…An innovative approach to the study of ancient diet is the analysis of dental calculus ( Fig. 1) (Middleton and Rovner, 1994;Fox et al, 1996;Nelson, 1997;Reinhard et al, 2001a,b).…”

“…Dental calculus consists of microfossils, including a variety of phytoliths (silica or calcium oxalate bodies) and starch grains, trapped into the carbonate calculus matrix (Fox et al, 1996). How exactly the dental calculus develops is not yet fully understood (Hazen, 1995).…”

Evaluating microfossil content of dental calculus from Brazilian sambaquis

“…In contrast to Reinhard et al (2001) and Fox et al (1996), we find that starch granules are the most common microfossil type encountered in dental calculus. We recommend that the dental calculus analysts be prepared for starch analysis by preparing starch reference collections and by using compound microscopes with polarized light capabilities to view interference crosses in starch granules.…”