Effectiveness of buccal dental‐microwear texture in African Cercopithecoidea dietary discrimination

Abstract

Objectives: This study compares ISO (ISO/FDIS 25178) roughness parameters, calculated from three-dimensional (3D) molar buccal microtexture surfaces, among African Cercopithecoidea primates with different diets. Materials and Methods:We examined 98 lower second molars from seven African Cercopithecoidea species with diverse dietary regimes and habitat exploitation. Buccal dental surfaces were analyzed using a Sensofar Plu Neox laser scanning confocal microscope. Thirty-eight, areal surface texture parameters were extracted (Mountain 7 ® software). Uni-and multivariate statistics were used to obtain diet-related patterns of buccal-microwear textures and feeding ecology to differentiate between species.Results: Buccal-dental 3D texture parameters discriminate between Cercopithecoidea diets. Analysis of variance (ANOVA) revealed significant variation in microwear texture between forest-adapted Mandrillus sphinx, which showed coarse flat features, and grassland forager Theropithecus gelada, whose buccal surfaces were characterized by a high density of thin features. Buccal-microwear textures of folivorous species (Colobus polykomos) were related to a lower density of thicker surface indentations in comparison to Papio anubis and Cercocebus atys which are adapted to the consumption of tough and hard foods. The limited interspecific variation in the buccalmicrowear textures of savanna dwellers (Chlorocebus pygerythrus and Chlorocebus aethiops) probably reflects similarities in their foraging diets.Discussion: Significant variations between-species demonstrate that 3D microwear ISO roughness parameters applied to buccal enamel surfaces can distinguish between the diets of Cercopithecoidea.

Multiproxy approach to reconstruct fossil primate feeding behavior: Case study for macaque from the Plio-Pleistocene site Guefaït-4.2 (eastern Morocco)

“…The Gaussian filter was applied because is widely used for technical surfaces and was applied after the trimming because it is sensitive to outliers (Schulz et al, 2013). Surface roughness was later quantified according to 38 ISO 25178/ISO 12781 parameters (Martínez et al, 2022;Supplementary Table 5).…”

“…To standardize the measured area on the buccal surface, we calculated the median of the parameters derived from the several (one to four) measurements of a single buccal surface (Scott et al, 2006;Calandra et al, 2012;Martínez et al, 2022), and used the median per specimen for analysis. We used log-transformed texture data for analyses because some texture parameters have non-normal distributions (Shapiro-Wilk, p < 0.05).…”

“…Positive casts were made with Ferropur (Feroca ® ) polyurethane (Martínez et al, 2022). Buccal areas were obtained using a Sensofar Plu Neox laser scanning confocal microscope, with a 20× (0.45NA) objective, a spatial sampling of 0.83 μm, an optical resolution of 0.31 μm, a vertical resolution of 20 nm, and a z-step interval of 1 μm (Ibáñez et al, 2020;Martínez et al, 2022).…”

“…Positive casts were made with Ferropur (Feroca ® ) polyurethane (Martínez et al, 2022). Buccal areas were obtained using a Sensofar Plu Neox laser scanning confocal microscope, with a 20× (0.45NA) objective, a spatial sampling of 0.83 μm, an optical resolution of 0.31 μm, a vertical resolution of 20 nm, and a z-step interval of 1 μm (Ibáñez et al, 2020;Martínez et al, 2022). Buccal surfaces were placed perpendicular to the objective in a horizontal position and an image of the field of view of the microscope (600 μm × 500 μm) was obtained (see 3D photosimulations in Supplementary Figure 3).…”

“…To ensure we did not exclude any parameter (e.g., Ssk has negative values), we log transformed the data as log [1 + parameter] (Supplementary Table 6). We identified the outliers for both original and log-transformed variables according to their Studentized residual values (absolute value > 3) and removed them from the final data set (Schulz et al, 2013;Martínez et al, 2022). To test the null hypothesis that microwear textures do not differ between teeth from different species, we applied analysis of variance (ANOVA) with pairwise testing (Tukey's honest significant difference [HSD]) to each texture parameter for each species.…”