Buccal dental microwear analyses support greater specialization in consumption of hard foodstuffs for Australopithecus anamensis

Ferran Estebaranz, Jordi Galbany, Laura M Martínez, Daniel Turbón & Alejandro Pérez-Pérez (2012, accepted) Buccal dental microwear analyses support greater specialization in consumption of hard foodstuffs for Australopithecus anamensis. Journal of Anthropological Sciences.

Molar occlusal microwear texture and anisotropy analyses of 3 Australopithecus anamensis fossil specimens have shown complexity values similar to those of Au.afarensis,indicating that neither of these hominin species had a diet dominated by hard food. However, many researchers have suggested that these were some of the earliest hominins to have such diets. Here we examine buccal microwear patterns of 5 Au. anamensis, 26 Au. afarensis, 48 Hominoidea and 80 Cercopithecoidea primate specimens for independent evidence of dietary adaptations of Au. anamensis. The buccal microwear results obtained suggest that the diet of Au.anamensis relied heavily on hard, brittle food, at least seasonally. This is similar to the diet of the extant Cercopithecoidea primates, including Papio anubis and Chlorocebus aethiops, both of which live in wooded, seasonal savannah environments and have diets that include fruit and grasses, but also underground storage organs (USOs), such as corms or blades, as well as leaves and seeds, and also Mandrillus and Cercocebus, from forested environments with frugivorous-granivorous diets. Furthermore, the buccal microwear patterns of Au.anamensis and Au.afarensis clearly differed –in clear contrast to occlusal enamel texture observations–, which support previous dietary interpretations based on both anatomical and palaeocological reconstructions.

Keywords: hominin, diet, feeding ecology, buccal microwear, fallback food, Australopithecus anamensis

Short and long-term in vivo human buccal-dental microwear turnover.

Romero A, Galbany J, De Juan J, Pérez-Pérez A (2012). Short and long-term in vivo human buccal dental-microwear turnover. American Journal of Physical Anthropology. DOI: 10.1002/ajpa.22054

Buccal–dental microwear depends on the abrasive content of chewed foodstuffs and can reveal long-term dietary trends in human populations. However, in vivo experimental analyses of buccal microwear formation processes are scarce. Here, we report the effects of an abrasive diet on microwear rates in two adult volunteers at intervals of 8 days over a period of 1 month and document long-term turnover over 5 consecutive years in the same subjects under an ad libitum Mediterranean diet. Buccal microwear was analyzed on mandibular first molars using high-resolution replicas and scanning electron microscopy. Microwear turnover was assessed by recording the scratches lost and gained at each time point. Our results indicate that scratch formation on enamel surfaces increased with a highly abrasive diet compared to both pre-test and post-test ad libitum dietary controls. In the long-term analysis, scratch turnover was higher than expected, but no significant long-term trends in microwear density or length were observed, because microwear formation was compensated by scratch disappearance. Our results confirm that buccal microwear patterns on mandibular molars show a dynamic formation process directly related to the chewing of abrasive particles along with ingested food. In addition, the observed long-term stability of buccal microwear patterns makes them a reliable indicator of overall dietary habits.

KEY WORDS: teeth, buccal surface, SEM, dental microwear, turnover.

Análisis del error de medición y variabilidad interespecífica morfométrica de Fourier en M2 de primates Hominoidea / Error rates and interespecific variability in mophometric Fourier analysis in M2 Hominoidea primates

Gamarra B, Romero A, Pérez-Pérez A & Galbany J (2011) Análisis del error de medición y variabilidad interespecífica morfométrica de Fourier en M2 de primates Hominoidea / Error rates and interespecific variability in mophometric Fourier analysis in M2 Hominoidea primates. Revista Española de Antropología Física 32: 56-66.

Fourier analyses allow extracting parameters from the outline of tooth crowns, which can be used in multivariate analyses. However, the great complexity of some dental shapes forces to check for the intrinsic error produced in this procedure. The main goal of this paper is to apply and validate the Fourier analysis in the study of second lower molar (M2) crown shape of four Hominoidea species to explore the interspecific morphometric variability, as well as determine the intra- and interobserver error rates. The occlusal surfaces outlines were digitized, derived Fourier functions were calculated, and Discriminant Analyses and Mantel Tests (Pearson correlations) were performed in order to determine the error rates between measurements and interspecific tooth shape variability. Results show that Fourier analyses are able to discriminate variability of molar shapes within Hominoidea primate species. In addition, the high correlation found, both intra- (r>0.9) and inter-observers (r>0.7) suggest that tooth morphometric description by Fourier methods from different observers can be pooled for joint analyses.

Keywords: Hominoidea, tooth, shape, elliptic Fourier analysis.

Resumen
Los análisis de Fourier permiten caracterizar el contorno del diente y obtener una serie de parámetros para un posterior análisis multivariante. Sin embargo, la gran complejidad que presentan algunas formas obliga a determinar el error de medición intrínseco que se produce. El objetivo de este trabajo es aplicar y validar los análisis de Fourier en el estudio de la forma dental del segundo molar inferior (M2) de cuatro especies de primates Hominoidea para explorar la variabilidad morfométrica interespecífica, así como determinar el error de medición a un nivel intra- e interobservador. El contorno de la superficie oclusal del diente fue definido digitalmente y con las funciones derivadas del análisis de Fourier se realizaron Análisis Discriminantes y Test de Mantel (correlaciones de Pearson) para determinar las diferencias de forma a partir de las mediciones tomadas. Los resultados indican que el análisis de Fourier muestra la variabilidad de forma en dientes molares en especies de primates Hominoidea. Adicionalmente, los altos niveles de correlación a nivel intra- (r>0,9) como inter-observador (r>0,7) sugieren que la descripción morfométrica del diente a partir de métodos de Fourier realizados por diferentes observadores puede ser agrupada para posteriores análisis.

Palabras clave: Hominoidea, diente, forma, análisis elíptico de Fourier.

Caracterización morfólogica del M2 de primates Hominoidea a partir de análisis de Fourier/ Morphological characterization of the Hominoidea primates second molars from Fourier analysis

Beatriz Gamarra, Alejandro Romero, Alejandro Pérez-Pérez, Jordi Galbany (2011) Caracterización morfólogica del M2 de primates Hominoidea a partir de análisis de Fourier/ Morphological characterization of the Hominoidea primates second molars from Fourier analysis. Revista Argentina de Antropología Biológica 13(1): 29-41.

Fourier analysis can allow to characterize the shape of teeth, by employing a number of landmarks defining its profile, and extract a number of parameters for subsequent multivariate analysis. However, the great complexity of some cases requires testing how many landmarks are needed for a correct representation. The aim of this paper is to apply and validate the Fourier analysis (Polar and Elliptic) in the dental conformation study by using different contour landmarks, and explore the morphometric variability in different genera. Digital photographs were obtained in occlusal view of second lower molars (M2s) of 4 species of primates (Hylobates moloch, Gorilla beringei graueri, Pongo pygmaeus pygmaeus and Pan troglodytes schweirfurthii). Teeth was defined with 30, 40, 60, 80, 100 and 120 landmarks, and 10 harmonics were obtained in each case. The variability was analyzed by applying Discriminant Analysis and NP-MANOVA from distance matrices to determine the percent of correct classification at methodological and taxonomical levels. The results shown that Fourier analysis detect intergenus variability of shape in M2s of Hominoidea genera, regardless of the number of landmarks defining the contour. The classification rates presented higher variability in Polar (≈60-90) analysis than in Elliptic ones (75-100%). Using between 60-100 landmarks in an elliptic analysis ensures a good discrimination of tooth shapes in Hominoidea
KEY WORDS: Fourier analysis; molar; primate; Hominoidea

RESUMEN
Los análisis de Fourier permiten caracterizar el contorno del diente a partir de un número determinado de puntos y extraer una serie de parámetros para un posterior análisis multivariante. No obstante, la gran complejidad que presentan algunas conformaciones obliga a comprobar cuántos puntos son necesarios para una correcta representación de ésta. El
objetivo de este trabajo es aplicar y validar los análisis de Fourier (Polar y Elíptico) en el estudio de la forma dental a partir de diferentes puntos de contorno y explorar la variabilidad morfométrica en diferentes géneros. Se obtuvieron fotografías digitales de la superficie oclusal en segundos molares inferiores (M2s) de 4 especies de Primates (Hylobates moloch, Gorilla beringei graueri, Pongo pygmaeus pygmaeus y Pan troglodytes schweirfurthii) y se definió su contorno con 30, 40, 60, 80, 100 y 120 puntos y su representación formal a 10 armónicos. El análisis de la variabilidad morfométrica se analizó mediante la aplicación de Análisis Discriminantes y un NP-MANOVA a partir de matrices de distancias para determinar la variabilidad y porcentajes de clasificación correcta a nivel metodológico y taxonómico. Los resultados indicaron que los análisis de forma con series de Fourier permiten analizar la variabilidad morfométrica de M2s en géneros de Hominoidea, con independencia del número de puntos de contorno (30 a 120). Los porcentajes de clasificación son más variables e inferiores con el uso de la serie Polar (≈60-90) que con la Elíptica (75-100%). Un número entre 60-100 puntos de contorno mediante el método elíptico garantiza una descripción correcta de la forma del diente.
PALABRAS CLAVE: Análisis de Fourier; molar; primate; Hominoidea

Age and individual foraging behavior predict tooth wear in Amboseli baboons

Galbany J, Altmann J, Pérez-Pérez A, Alberts SC (2011) Age and individual foraging behavior predict tooth wear in Amboseli baboons. American Journal of Physical Anthropology 144(1): 51-59.

Teeth represent an essential component of the foraging apparatus for any mammal, and tooth wear can have significant implications for survival and reproduction. This study focuses on tooth wear in wild baboons in Amboseli, southern Kenya. We obtained mandibular and maxillary tooth impressions from 95 baboons and analyzed digital images of replicas made from these impressions. We measured tooth wear as the percent dentine exposure (PDE, the percent of the occlusal surface on which dentine was exposed), and we examined the relationship of PDE to age, behavior, and life history variables. We found that PDE increased significantly with age for both sexes in all three molar types. In females, we also tested the hypotheses that long-term patterns of feeding behavior, social dominance rank, and one measure of maternal investment (the cumulative number of months that a female had dependent infants during her lifetime) would predict tooth wear when we controlled for age. The hypothesis that feeding behavior predicted tooth wear was supported. The percent of feeding time spent consuming grass corms predicted PDE when controlling for age. However, PDE was not associated with social dominance rank or maternal investment.

KEY WORDS aging; feeding behavior; foraging; Papio cynocephalus

Tooth size variation related to age in Amboseli baboons

Galbany J, Dotras L, Alberts SC & Pérez-Pérez A (2010) Tooth size variation related to age in Amboseli baboons. Folia Primatologica 81(6): 348-359.

We measured the molar size from a single population of wild baboons from Amboseli (Kenya), both females (n = 57) and males (n = 50). All the females were of known age; the males represented a mix of known-age individuals (n = 31) and individuals with ages estimated to within 2 years (n = 19). The results showed a significant reduction in the mesiodistal length of teeth in both sexes as a function of age. Overall patterns of age-related change in tooth size did not change whether we included or excluded the individuals of estimated age, but patterns of statistical significance changed as a result of changed sample sizes. Our results demonstrate that tooth length is directly related to age due to interproximal wearing caused by M2 and M3 compression loads. Dental studies in primates, including both fossil and extant species, are mostly based on specimens obtained from osteological collections of varying origins, for which the age at death of each individual in the sample is not known. Researchers should take into account the phenomenon of interproximal attrition leading to reduced tooth size when measuring tooth length for ondontometric purposes.

Keywords: molar size, interproximal wearing, aging, Papio cynocephalus, Amboseli, Kenya

Origen y evolución de los dientes: de los cordados primitivos a los humanos modernos

Pérez-Pérez A, Galbany J, Romero A, Martínez LM, Estebaranz F, Pinilla B & Gamarra B (2010) Origen y evolución de los dientes: de los cordados primitivos a los humanos modernos. Revista Española de Antropología Física 31: 167-192.

Los dientes de los vertebrados, y especialmente de los mamíferos, muestran una gran diversidad de formas como resultado de las adaptaciones ecológicas y alimentarias de las especies en función del hábitat y las condiciones ecológicas. La anatomía dental es de gran utilidad para definir especies y caracterizar poblaciones, y se ha utilizado extensamente para definir nuevos taxones y establecer relaciones filogenéticas. Nuestras investigaciones sobre la evolución morfológica de la dentición de los homininos han puesto de relieve la importancia de los dientes en la caracterización de las adaptaciones ecológicas de nuestros antepasados. El presente trabajo es el primero de una serie de tres trabajos que nos planteamos sobre la importancia de las características anatómicas en la interpretación de la evolución de nuestro linaje. En él se describen los principales eventos evolutivos que dieron origen a los dientes y su diversificación.

Palabras clave
dientes, anatomía, evolución, mamíferos, primates, homininos

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Origin and evolution of teeth: from the primitive chordates to modern humans

Abstract
The teeth of vertebrates, especially mammals, show a great diversity of forms as a result of ecological and dietary adaptations in relation to habitat preferences and ecological conditions. The dental anatomy is useful to define and characterize populations and species, and has been used extensively to define new taxa, and
phylogenetic relationships among groups. Our research on the morphological evolution of the hominin dentition has highlighted the importance of the teeth in the characterization of the diet and the ecological adaptations of our ancestors. This study is the first in a series of three papers in which we consider the importance of
the dental anatomical features in the interpretation of the evolution of our lineage. It describes the major evolutionary events that gave rise to the teeth and their diversification. In subsequent works we will analyze in greater detail the diversification of the teeth of mammals and primates.

Key words
teeth, anatomy, evolution, mammals, primates, hominins

The life history context of reproductive aging in a wild primate model

Altmann J, Gesquiere L, Galbany J, Onyango PO, Alberts SC (2010) The life history context of reproductive aging in a wild primate model. Annals of the New York Academy of Sciences 1204: 127-138

The pace of reproductive aging has been of considerable interest, especially in regard to the long postreproductive period in modern women. Here we use data for both sexes from a 37-year longitudinal study of a wild baboon population to place reproductive aging within a life history context for this species, a primate relative of humans that evolved in the same savannah habitat as humans did. We examine the patterns and pace of reproductive aging, including birth rates and reproductive hormones for both sexes, and compare reproductive aging to agerelated changes in several other traits. Reproductive senescence occurs later in baboon females than males. Delayed senescence in females relative to males is also found in several other traits, such as dominance status and body condition, but not in molar wear or glucocorticoid profiles. Survival, health, and well-being are the product of risk factors in morphological, physiological, and behavioral traits that differ in rate of senescence and in dependence on social or ecological conditions; some will be very sensitive to differences in circumstances and others less so.

Keywords: reproductive aging; baboons; toothwear; body condition; steroid hormones; senescence

Un macaco d’època Romana enterrat a Llívia

Guàrdia J, Maragall M, Mercadal O, Olesti O, Galbany J & Nadal J (2010) Un macaco d’època Romana enterrat a Llívia. Ker – Revista del Grup de Recerca de Cerdanya 3: 26-39.

Testing hypotheses of dietary reconstruction from buccal dental microwear in Australopithecus afarensis

F Estebaranz, L M Martínez, J Galbany, D Turbón, A Pérez-Pérez (2009) Testing hypotheses of dietary reconstruction from buccal dental microwear in Australopithecus afarensis. Journal of Human Evolution 57: 739-750.

A recent study of occlusal microwear in Australopithecus afarensis described this species as an opportunistic dweller, living in both forested and open environments and greatly relying on fallback resources and using fewer food-processing activities than previously suggested. In the present study, analysis of buccal microwear variability in a sample of A. afarensis specimens (n = 75 teeth) showed no significant correlations with the ecological shift that took place around 3.5 Ma in Africa. These results are consistent with the occlusal microwear data available. In fact, significant correlations between buccal and occlusal microwear variables were found. However, comparison of the buccal microwear patterns showed clear similarities between A. afarensis and those hominoid species living in somewhat open environments, especially the Cameroon gorillas. A diet based mainly on succulent fruits and seasonal fallback resources would be consistent with the buccal microwear patterns observed.

Buccal dental microwear variability in extant African Hominoidea: taxonomy versus ecology

J Galbany, F Estebaranz, L M Martínez, A Pérez-Pérez  (2009)  Buccal dental microwear variability in extant African Hominoidea: taxonomy versus ecology  Primates  50:  3.  221-230.

Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have been used to trace the dietary habits of fossil species, including primates and hominids. However, few studies have addressed the variability of this microwear. The abrasiveness of dietary components depends not only on the hardness of the particles ingested, but also on the presence of dust and other exogenous elements introduced during food processing. These elements are responsible for the microwear typology observed on the enamel surfaces of primate teeth. Here we analyzed the variability of buccal microwear patterns in the great African Great Apes (Gorilla gorilla and Pan troglodytes), using tooth moulds obtained from the original specimens held in several osteological collections. Our results suggest that ecological adaptations at subspecies or population level account for differences in microwear patterns, which are attributed to habitat and ecological conditions within populations rather than differences between species. The findings from studies on the variability of buccal dental microwear in extant species will contribute to a better understanding of extinct hominids’ diet and ecology.

Microdesgaste y patología dental en la población de la Edad de Bronce de “Mar i Muntanya” (Alella, Barcelona)

J Galbany, N Garriga, M Majoral, R Coll, J Fluxà  (2008)  Microdesgaste y patología dental en la población de la Edad de Bronce de “Mar i Muntanya” (Alella, Barcelona).  Revista Española de Antropología Física  28:  25-34

Dental microwear and dental pathology in Bronze Age in Alella (Barcelona) In 1947, a Bronze Age necropolis was discovered in “Mar i Munyanya”, located in Alella village (El Maresme, Barcelona). Since now, only 33 remains have been well preserved, mainly belonging to mandibles, maxilla and neurocranium. The present work has been focused in recovered teeth, principally in dental pathology from the same period, and dental microwear pattern in comparison to other human populations. Results show a similar prevalence in several dental pathologies between all these populations, including “Mar i Muntanya”, and dental microwear pattern indicate that this population may had a more abrasive diet than modern hunter-gatherer populations, and similar to other Bronze-Age populations. Key words: dental microwear, Bronze Age, SEM, feeding ecology

Enterrament d’època tardoromana d’un macaco amb “aixovar” al jaciment de Les Colomines (Llívia, La Cerdanya)

J Guàrdia, M Maragall, O Mercadal, O Olesti, J Galbany, J Nadal (2007) Enterrament d’època tardoromana d’un macaco amb “aixovar” al jaciment de Les Colomines (Llívia, La Cerdanya). Empúries 55: 199-227

El yacimiento de Les Colomines se ubica en una franja de terreno situada al pie del puig del Castell, al norte de la villa de Llívia (La Cerdanya). La intervención arqueológica se efectuó entre 1997 y 2001 como consecuencia de un proyecto de urbanización. En esta última se descubrió la tumba de un macaco (Macaca sylvanus), junto a un “ajuar” asociado al primate, de piezas metálicas pertenecientes a otros tantos cinturones de tradición militar romana bajoimperial. La relación estratigráfica de la tumba y el material apuntan una cronología, para el enterramiento, de siglo V-VI. La tumba se relaciona con la fase 3 y última de la ocupación del asentamiento, caracterizada por la compartimentación de una planta inicial regular perteneciente a un gran edificio público levantado durante los siglos I y II. En relación al individuo en cuestión, se llevó a cabo un estudio osteológico y biométrico, lo que permitió caracterizarlo a nivel de especie, edad y sexo, así como un análisis del patrón de microestriación dentaria, y paralelamente un profundo estudio del contexto histórico. macaco, tumba, Roma, Iulia Libica, Catalunya.

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In 2001 was discovered, in the site of Les Colomines (Llívia, Cerdanya), the remains of an african monkey’s burial, a macaque (Macaca sylvanus), containing the skeleton of the animal, with some objects. This group consisted basically in decorated metalic pieces; we can speak, among them, about some bronze military belt fittings, used in the Late Roman Empire. After the excavation, we agree to think all this objects were disposed in the moment of the burial. Chronologically, this whole belongs to the V-VI centuries A.D. (Studying this material and the stratigraphic relations of this structure, we can associate this tomb with the third phase of occupation of Les Colomines. This settlement, caracterized by important structures, including habitations, and materials (specially ceramics, but also an epigraphic inscription), was a public building (maybe a forum), during the romanization period and after (I-II centuries A.D.). In their third phase, along with the tomb, we discovered an important reestructuration of the buildings, and a group of 204 coins from the period. The interpretation of the tomb and its caracteristics can be associated with diferents military struggles to control the strategic Pyrennes in the last stages of Roman control of Hispania, between different emperors, and between the Roman Imperial Army and the Barbarians also. Possibly this macacus belonged to an official or a general. Once recuperated, osteological and biometric studies have been made with the bones, and complementary studies about the age, sex, and teeth also. No other exemple has been discovered in the classical world with this caracteristics). macaque, burial, Rome, Iulia Libica, Catalonia.

Enterramiento de un macaco con ajuar de época tardo-romana en el yacimiento de Les Colomines (Llívia, La Cerdanya, Girona)

J Guàrdia, M Maragall, O Mercadal, O Olesti, J Galbany, J Nadal  (2006)  Enterramiento de un macaco con ajuar de época tardo-romana en el yacimiento de Les Colomines (Llívia, La Cerdanya, Girona).  Animalia (vol. Especial Congreso AVEPA):  42-44.

Tamaño dental, desgaste oclusal y microestriación dentaria en primates Hominoidea

J Galbany, A Pérez-Pérez  (2006)  Tamaño dental, desgaste oclusal y microestriación dentaria en primates Hominoidea.  Revista Española de Antropología Física  26:  9-15.

Dental microwear patterns in the human dentition are mainly caused by the composition of the diet, but also by the presence of dust, ash or other abrasive particles on the ingested food items. The present study analyzes how this pattern is affected by other variables independent to the type of foods eaten, such as dental size and gross occlusal wear. Dental moulds of Hominoidea molars were obtained from original specimens curated at osteological collections. The buccal microwear patterns were analyzed in all the teeth, and its crown size (AOT, total occlusal area) and overall occlusal wear (PED, percent of dentine exposure) were measured using a new quantitative semiautomatic methodology. The results obtained suggest that no significant relationships exist between the buccal microwear patterns measured and dental size and occlusal. These indicate that the activities associated to occlusal chewing are independent to diet composition, and that other masticatory activities, not directly related to diet composition, might better explain the evolution of tooth size and enamel thickness. Key words: dental microwear, tooth size, occlusal wear, Primates, Hominoidea.

Nota metodológica: Alteración del patrón de microestriación dentaria por el efecto wrinkle

F Estebaranz, J Galbany, L M Martínez, B Pinilla, A Pérez-Pérez  (2006)  Nota metodológica: Alteración del patrón de microestriación dentaria por el efecto wrinkle.  Revista Española de Antropología Física  26:  115-121.

We describe the wrinkle effect for the first time on tooth molds made with epoxy resine and sputter-coated with gold for SEM observation. To determine to what extent it can affect the buccal microwear pattern on dental enamel, we analyze two dental samples including three Hominoidea subspecies. One of the samples includes teeth affected by wrinkles during sputtering. We have observed a significant decrease in the dental microwear variability in the affected sample, although no significant differences are observed. The wrinkle effect reduces the percent of subspecies correct classification in the sample with affected teeth when applying a Discriminant Analysis to the buccal microwear anr roughnes variables. It seems convenient to reject affected tooth molds for SEM analyses of dental microwear. Key words: microwear, SEM, wrinkle effect.

Comparative analysis of dental enamel polyvinylsiloxane impression and polyurethane casting methods for SEM research

J Galbany, F Estebaranz, L M Martínez, A Romero, J De_Juan, D Turbón, A Pérez-Pérez  (2006)  Comparative analysis of dental enamel polyvinylsiloxane impression and polyurethane casting methods for SEM research.  Microscopy Research and Technique  69:  (2).  246-252.

KEY WORDS dental microwear; polyvinylsiloxane; epoxy; SEM ABSTRACT Dental casting is a very common procedure for making high-quality replicas of paleo-anthropological remains. Replicas are frequently used, instead of original remains, to study both fossil and extant Primate teeth in morphological and metrical analyses. Several commercial products can be used in molds. This study analyzed SEM image resolution and enamel surface feature definition of tooth molds at various magnification levels and obtained, with both Colte`ne1 and 3MTM low-viscosity body polyvinylsiloxane impression, materials and polyurethane casts. Results, through comparison with the original teeth, show that both the negative molds and the positive casts are highly reliable in replicating enamel surfaces. However, positive cast quality is optimal for SEM observation only till the fourth consecutive replica from the original mold, especially at high SEM magnification levels.

Microestriación y modo de vida

J Galbany  (2006)  Microestriación y modo de vida.  Boletín de la Sociedad Castellonense de Cultura  LXXXII:  5-19.

Dental microwear variability on buccal tooth enamel surfaces of extant Catarrhini and Miocene fossil Dryopithecus laietanus (Hominoidea)

J Galbany, S Moyà-Solà, A Pérez-Pérez  (2005)  Dental microwear variability on buccal tooth enamel surfaces of extant Catarrhini and Miocene fossil Dryopithecus laietanus (Hominoidea).  Folia Primatologica  76:  (6).  325-341.

Analyses of buccal tooth microwear have been used to trace dietary habits of modern hunter-gatherer populations. In these populations, the average density and length of striations on the buccal surfaces of teeth are significantly correlated with the abrasive potential of food items consumed. In non-human primates, tooth microwear patterns on both occlusal and buccal wear facets have been thoroughly studied and the results applied to the characterization of dietary habits of fossil species. In this paper, we present inter- and intra-specific buccal microwear variability analyses in extant Cercopithecoidea (Cercopithecus mitis, C. neglectus, Chlorocebus aethiops, Colobus spp., Papio anubis) and Hominoidea (Gorilla gorilla, Pan troglodytes, Pongo pygmaeus). The results are tentatively compared to buccal microwear patterns of the Miocene fossils Dryopithecus and Oreopithecus. Significant differences in striation density and length are found among the fossil taxa studied and the extant primates, suggesting that buccal microwear can be used to identify dietary differences among taxa. The Dryopithecus buccal microwear pattern most closely resembles that of abrasive, tough plant foods consumers, such as the gorilla, in contrast to studies of dental morphology that suggest a softer, frugivorous diet. Results for Oreopithecus were equivocal, but suggest a more abrasive diet than that previously thought.

Error rates in dental buccal microwear quantification using Scanning Electron Microscopy

J Galbany, L M Martínez, H M López-Amor, V Espurz, O Hiraldo, A Romero, J De_Juan, A Pérez-Pérez  (2005)  Error rates in dental buccal microwear quantification using Scanning Electron Microscopy.  Scanning  27:  23-29.

Dental microwear, usually analyzed using scanning electron microscopy (SEM) techniques, is a good indicator of the abrasive potential of past human population diets. Scanning electron microscopy secondary electrons provide excellent images of dental enamel relief for characterizing striation density, average length, and orientation. However, methodological standardization is required for interobserver comparisons since semiautomatic counting procedures are still used for micrograph characterization. The analysis of normally distributed variables allows the characterization of small interpopulation differences. However, the interobserver error rates associated with SEM experience and the degree of expertise in measuring striations are critical to population dietary interpretation. The interobserver comparisons made here clearly indicate that the precision of SEM buccal microwear measurements depends heavily on variable definition and the researcher’s expertise. Moreover, error rates are not the only concern for dental microwear research. Low error rates do not guarantee that all researchers are measuring the same magnitudes of the variables considered. The results obtained show that researchers tend to maintain high intrapopulation homogeneity and low measurement error rates, whereas significant interobserver differences appear. Such differences are due to a differential interpretation of SEM microwear features and variable definitions that require detailed and precise agreement among researchers. The substitution of semiautomatic with fully automated procedures will completely avoid interobserver error rate differences. Key words: dental microwear, error rates, scanning electron microscopy, quantification

Enterrament d'època tardoromana corresponent a un macaco amb aixovar al jaciment de Les Colomines (Llívia)

J Guàrdia, M Maragall, O Mercadal, O Olesti, J Galbany, J Nadal  (2005)  Enterrament d'època tardoromana corresponent a un macaco amb aixovar al jaciment de Les Colomines (Llívia).  Ceretania - Quaderns d'Estudis Cerdans  4:  65-106.

Buccal enamel microwear variability in Cercopithecoidea Primates as a reflection of dietary habits in forested and open savanna environments

J Galbany, A Pérez-Pérez  (2004)  Buccal enamel microwear variability in Cercopithecoidea Primates as a reflection of dietary habits in forested and open savanna environments.  Anthropologie  42:  13-19.

Dental microwear analysis has proved to be a good indicator of diet and dietary related behaviour in modern humans, fossil hominids and primates. The composition of the diet and the presence of dust and other abrasive particles, are related to microwear rates on the buccal enamel surfaces of molar teeth. Plant food materials such as leaves or stems include phitoliths in larger quantities than fruits or meat. These particles may scratch the enamel surface of teeth during mastication producing a microwear pattern that may be indicative of food choice and food preferences within primate species. In this study we present a dental microwear analysis of extant Cercopithecoidea primates, based on the analysis of more than 200 dental casts obtained from the osteological collection of the National Museum of Kenya (NMK). Specific, sub-specific and also ecological differences are shown to underlie the buccal microwear variability observed within the studied sample. KEYWORDS: Non-occlusal dental microwear – Microstriation – Primates – Cercopithecoidea

Tooth replication techniques, SEM imaging and microwear analysis in Primates: methodological obstacles

J Galbany, L M Martínez, A Pérez-Pérez  (2004)  Tooth replication techniques, SEM imaging and microwear analysis in Primates: methodological obstacles.  Anthropologie  41:  5-12.

Dental microwear analyses are among the most significant techniques though which a researcher can make dietary and ecological inferences from primate fossil specimens. Hard particles, such as plant phytoliths or silica-base sands, can scratch tooth enamel surfaces during food mastication producing a dietary specific pattern of microwear on the enamel surface. The density, axis length and orientation of microwear features, either striations or pits, are highly informative of dietary habits in both extant and fossil primates. The analysis of tooth enamel surfaces requires the use of scanning electron microscopy (SEM) techniques, because of its high resolution power, including gold-coating of teeth for observation. Problems arise when specimens to be analysed are unique and there is no possibility of a direct observation with an environmental microscope. Negative moulds must then be made and silicone-base components are indicated for high quality replication of enamel surfaces. A positive cast needs to be obtained, and epoxy-base resins are frequently used for their good quality and durability. However, successive silicon and epoxy replications result in the loosing of surface detail and precision. Surface observation errors can also be caused be the SEM technology itself, especially if back-scattered electrons are used instead of secondary electrons for maximizing the topographical information of enamel images. This paper reviews the most commonly used methodological approaches to tooth moulding and casting, comparing SEM micrographs of casts with actual tooth surfaces, and contrasting the reliability of SEM images for dietary interpretation of tooth microwear in both extant and fossil primates. KEYWORDS: Scanning Electron Microscopy – Epoxy resin – Tooth cast – Polyvinylsiloxane impression – Microwear – Primates

Palaeodemography and dental microwear pattern of Homo habilis in East Africa

L M Martínez, J Galbany, A Pérez-Pérez  (2004)  Palaeodemography and dental microwear pattern of Homo habilis in East Africa.  Anthropologie  42:  53-58.

We have studied the variability of the buccal microwear pattern in the Homo habilis population from Olduvai Gorge (Tanzania) and East Rudolf (Kenya), as a dietary indicator in fossil hominin species, and its relationship to the age of the individuals analysed. The estimation of the age of the individuals was done by estimating the rate of dental occlusal wear of individuals of known age. The biodemographic population extinction pattern could be analysed, showing great similarities to that observed in other Paleolithic populations. In the studied sample, the results obtained show that the striation density of the buccal microwear pattern is not significantly correlated with the estimated age at death, despite a tendency towards an increase in the number of striations with age can be observed. Further analyses and greater samples are needed to draw meaningful results.KEYWORDS: Paleodemography – Buccal microwear – Hominins – Homo habilis

New evidence and interpretation of subvertical grooves in Neandertal teeth from Cueva de Sidrón (Spain) and Figueira Brava (Portugal)

J E Egocheaga, A Pérez-Pérez, L Rodríguez, J Galbany, L M Martínez, M Telles Antunes  (2004)  New evidence and interpretation of subvertical grooves in Neandertal teeth from Cueva de Sidrón (Spain) and Figueira Brava (Portugal).  Anthropologie  42:  49-52.

Interproximal tooth wear is caused by tooth-to-tooth rubbing that results in the formation of flat wear surfaces characterized by an intense pattern of enamel pitting caused by prism-plucking. The rate of wear of such surfaces depends on the forces involved in food processing and chewing. In some instances, the interproximal wear facets, mainly of molar teeth, show a number of subvertical grooves with a nearly vertical direction. These grooves are mostly present in Neanderthal teeth, but have also been described in some African fossil teeth and in European Homo heidelbergensis, as well as in several modern hunter-gatherer populations, such as Australian Aborigines. Subvertical grooves have seldom been attributed to taphonomic processes, although most probably they are caused by natural biomechanical processes during mastication of hard objects included in the diet. They have also been associated to acidic dietary habits given their radial disposition and their inter-digitalisation. The present study analyses the subvertical grooves observed in the Neanderthal dentition of Cueva de Sidrón (Spain). Comparisons are made with the similar interproximal grooves pattern observed in the Neanderthal specimen from Figueira Brava (Portugal) and some remains of H. heidelbergensis from Sima de los Huesos (Spain). Other cases have been described for the Neanderthal sites of Genay and Le Fate (France). The results obtained allow discarding a post-mortem origin of these structures, the most probable cause of the subvertical grooves being natural biomechanical chewing processes combined with some dietary habits indicative of hard plant foods ingestion. KEYWORDS: Subvertical grooves – Interproximal facets – Teeth – Neanderthals

Estudio del patrón de microestriación vestibular en algunos dientes del dolmen de Santa Margarita 3 (Portugal)

A Pérez-Pérez, J Galbany  (2003)  Estudio del patrón de microestriación vestibular en algunos dientes del dolmen de Santa Margarita 3 (Portugal).  Trabalhos de Arqueología  32:  422-431.

Variabilidad del patrón de microestriación dentaria en Primates Hominoideos: ¿cuestión de especie o de entorno ecológico?

J Galbany, L M Martínez, A Pérez-Pérez  (2002)  Variabilidad del patrón de microestriación dentaria en Primates Hominoideos: ¿cuestión de especie o de entorno ecológico?.  Revista Española de Antropología Física  23:  77-83.

El análisis del microdesgaste dentario es un buen indicador de la abrasividad de los alimentos consumidos por los Primates, y por los humanos y los Homínidos fósiles en particular. La abrasividad de la dieta es el resultado de la dureza de las partículas de alimento ingeridas, así como de la presencia de polvo y otras partículas externas, incorporadas al alimento durante su preparación, que son las causantes directas de la tipología de desgaste macroscópico y del microdesgaste del esmalte dental. El presente estudio analiza la variabilidad del microdesgaste dentario de las superficies vestibulares de los dientes de las grandes especies de Primates de la Superfamilia Hominoidea (Gorilla gorilla, Pan troglodytes y Pongo pygmaeus) a partir del estudio de moldes dentarios obtenidos de ejemplares originales de colecciones osteológicas de procedencia diversa. Al mismo tiempo se intentan explicar las posibles causas de dichos patrones de microestriación y como se relacionan con el hábitat ocupado por los diversos subgrupos poblacionales. Los resultados obtenidos sugieren que los procesos de adaptación ecológica son básicos en la configuración del patrón de microestriación dentaria, por encima de los modelos de diferenciación alimentaria a nivel de especie.

Estudio paleodemográfico de la población de Paranthropus boisei de los yacimientos de Olduvai (Tanzania), East Rudolf y West Turkana (Kenia)

L M Martínez, J Galbany, A Pérez-Pérez  (2002)  Estudio paleodemográfico de la población de Paranthropus boisei de los yacimientos de Olduvai (Tanzania), East Rudolf y West Turkana (Kenia).  Revista Española de Antropología Física  23:  85-91

En el presente trabajo se estudia el modelo paleodemográfico de la población de Paranthropus boisei constituida por los materiales fósiles de los yacimientos de Olduvai (Tanzania), West Turkana (Kenia) y East Rudolf (Kenia). Las estimaciones de edad de muerte de cada individuo se realizaron a partir de la tasa de desgaste dentario oclusal de especimenes de edad conocida de la población de Homo habilis de los mismos yacimientos estudiada anteriormente, que se aplicó a todos los dientes de P. boisei obteniéndose una edad por individuo que permitió realizar el estudio paleodemográfico de la población. Los resultados obtenidos, aunque limitados por la metodología aplicada, indican una elevada mortalidad en los individuos inmaduros, especialmente en los individuos juveniles, y un patrón demográfico en los primeros intervalos de edad diferente al de las poblaciones del género Homo estudiadas.