Quantitative Dental Mesowear Analysis in Domestic Caprids: a New Method to Reconstruct Management Strategies

Abstract

Dental mesowear is a widely used tool in archaeology and palaeontology for the reconstruction of the overall diet of mammals. This method is based on the characterisation of the height and relief of dental cusps, as they vary according to diet. The use of this method on domestic ungulates presents limitations because (1) currently, very few reference frameworks are available, and (2) the qualitative categorisation of cusps limits our observations and interpretations. In this work, we introduce the analysis of quantitative dental mesowear, based on the measurement of the angle and height of cusps from photographs. The use of this method on 26 present-day domestic sheep with two different feeding strategies showed very significant differences: the group with a dominant rangeland diet has high cusps with acute angles, and the group with a dominant grassland diet has lower cusps with obtuse angles. This method has been compared with the traditional technique of mesowear score, which consists in the qualitative categorisation of cusps into seven categories. However, the analysis showed that mesowear score is more prone to observer error than quantitative mesowear. In addition, quantitative mesowear better reflects the variability in dietary behaviours of extant sheep since observations are not limited into seven categories. To test quantitative mesowear in archaeological samples, we analysed caprine mesowear at two Iron Age sites (sixth-fifth centuries BC) from the northeast of the Iberian Peninsula: Empúries and Ullastret. The results show that caprids at the Ullastret site have a slightly more abrasive diet than at Empúries, which is consistent with data obtained from dental microwear in previous work. Overall, we show the potential of this technique, which can be combined with traditional techniques, to distinguish past caprine feeding strategies.

Evolutionary paleoecology of European rhinocerotids across the Oligocene-Miocene transition

“…All rhinocerotids studied fell within the range of C3 feeding for stable isotopy (δ 13 C diet < -22 ‰; Domingo et al, 2013), and in the range of browsers (0-2) or mixed-feeders (0.4-2.74) for mesowear (Jiménez-Manchón et al, 2021). Although extant grazers might have mesowear ruler scores as low as 2.09 ( Kobus ellipsiprymnus , Redunca redunca ), a grazing diet seems unlikely for late Oligocene – early Miocene rhinocerotids in Europe.…”

“…Each locality is detailed and discussed by chronological order. The dietary categorization is based on previous studies on extant herbivores (microwear: Scott, 2012;Hullot et al, 2019;mesowear: Rivals et al, 2020;Jiménez-Manchón et al, 2021). At Gaimersheim (MP28), the mesowear of M. gaimersheimense (2.25, n = 4) and the DMTA (low Str: high anisotropy) suggest a more abrasive diet than that of R. romani.…”

“…We only scored the paracone of upper molars (mostly M1-2, but two M3 were included) with an average wear (wear stages 4 to 7 from Hillman-Smith et al, 1986), and not the sharpest cusp (metacone or paracone), as significant differences have been noted between these two cusps in rhinoceros (Taylor et al, 2013; Hullot et al, 2021). With this approach, browsers have low scores (extant species between 0-2) and grazers high ones (2.09-5.47), while mixed-feeders have intermediate values (0.4-2.74; Jiménez-Manchón et al, 2021).…”

“…Each locality is detailed and discussed by chronological order. The dietary categorization is based on previous studies on extant herbivores (microwear: [55,56,61,65]).…”

Sharpening the mesowear tool: geometric morphometric analysis of cusp shape and diet in ruminants

“…Prior attempts to develop quantitative measures of mesowear involve measures of cusp heights and angles (Widga, 2006;Valli and Palombo, 2008;Fraser and Theodor, 2010;Loffredo and DeSantis, 2014;Saarinen et al, 2014;Jiménez-Manchón et al, 2021). However, as we reveal below, cusp shape varies in other ways.…”