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Taphonomic studies aim to identify the modifying agents that intervene in bone assemblages found at archaeopaleontological sites. Carnivores may modify, accumulate, or scavenge skeletal parts inflicting tooth marks, including scores, on the cortical surface. Several works have studied tooth score morphology to discern which carnivore group modified the bone assemblages, achieving different results. In the present study, different methods based on the use of landmarks and semilandmarks have been tested to describe and analyze the score profile cross-sections of spotted and brown hyenas, leopards, and lions. According to our results, the already published seven-landmark method is useful in order to differentiate between carnivore species from different families (e.g., felids and hyenids). Meanwhile, felid species (e.g., leopards and lions) cannot be consistently distinguished using any of the methods tested here. In contrast, hyenid species can be morphologically differentiated. On the other hand, the use of semilandmarks does not generally improve morphological characterization and distinction, but low numbers of landmarks and the inclusion of the score’s deepest point might provide the best results when semi-automatic semilandmark models are preferred to avoid sampling biases., Los estudios tafonómicos tienen como objetivo identificar los agentes modificadores que intervienen en los conjuntos óseos encontrados en sitios arqueopaleontológicos. Los carnívoros pueden modificar, acumular o hurgar en partes del esqueleto, provocando marcas de dientes, incluidas rayas, en la superficie cortical. Varios trabajos han estudiado la morfología de las incisiones dentales para discernir qué grupo de carnívoros modificaban los conjuntos óseos, logrando resultados diferentes. En el presente estudio, se han probado diferentes métodos basados ​​en el uso de puntos de referencia y semipuntos de referencia para describir y analizar las secciones transversales del perfil de puntuación de hienas, leopardos y leones pardos y manchados. Según nuestros resultados, el método de los siete hitos ya publicado es útil para diferenciar entre especies de carnívoros de diferentes familias (p. ej., félidos e hienidas). Mientras tanto, las especies de felinos (por ejemplo, leopardos y leones) no se pueden distinguir de manera consistente utilizando ninguno de los métodos probados aquí. Por el contrario, las especies de hiénidas pueden diferenciarse morfológicamente. Por otro lado, el uso de semipuntos de referencia generalmente no mejora la caracterización y distinción morfológica, pero un número bajo de puntos de referencia y la inclusión del punto más profundo de la puntuación podrían proporcionar los mejores resultados cuando se prefieren los modelos semiautomáticos de semipuntos de referencia para evitar sesgos de muestreo., Euskal Herriko Unibertsitatea, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Depto. de Prehistoria, Historia Antigua y Arqueología, Fac. de Geografía e Historia, TRUE, pub

Taphonomic studies aim to identify the modifying agents that intervene in bone assemblages found at archaeopaleontological sites. Carnivores may modify, accumulate, or scavenge skeletal parts inflicting tooth marks, including scores, on the cortical surface. Several works have studied tooth score morphology to discern which carnivore group modified the bone assemblages, achieving different results. In the present study, different methods based on the use of landmarks and semilandmarks have been tested to describe and analyze the score profile cross-sections of spotted and brown hyenas, leopards, and lions. According to our results, the already published seven-landmark method is useful in order to differentiate between carnivore species from different families (e.g., felids and hyenids). Meanwhile, felid species (e.g., leopards and lions) cannot be consistently distinguished using any of the methods tested here. In contrast, hyenid species can be morphologically differentiated. On the other hand, the use of semilandmarks does not generally improve morphological characterization and distinction, but low numbers of landmarks and the inclusion of the score’s deepest point might provide the best results when semi-automatic semilandmark models are preferred to avoid sampling biases.

Defining the time that any given archaeofaunal assemblage took to be accumulated is challenging. Understanding the time variable is crucial to interpret how early sites were formed and what these sites represent in terms of hominin behavior. Two complementary dental analysis techniques (microwear and mesowear) have been used to understand dietary niches of ungulates. Microwear has also specifically been used to detect the character of occupations at archaeological sites. Here, we apply these techniques to a selection of Olduvai sites. Microwear and mesowear analyses on bovid teeth from a set of anthropogenic sites (FLK Zinj, DS, BK) and a carnivore palimpsest (FLK North) yielded different results. Microwear data from the three anthropogenic sites are similar, reflecting short, seasonal occupations, in contrast with the carnivore assemblage, which suggests a more prolonged period of deposition. The similar microwear signal in the two pene-contemporaneous sites of FLK Zinj and DS is encouraging, but caution in its interpretation is applied because of limited tooth enamel preservation and the resulting small sample size. The results shown here must be considered as a baseline for future and more extensive studies. Both microwear and mesowear analyses show that the most common bovid taxa in the Bed I sites exhibit mixed feeding signals. This reinforces the caution about interpretations of dietary niches of extinct ungulates based on their modern counterparts and emphasizes that for some taxa, the adoption of a browsing or grazing diet is context (time and locus) specific.

Excavations at Bell Korongo (BK) have yielded important evidence to infer different behaviours of early hominins in several archaeological levels since 1935. The present study shows the results for a newly geological and archaeological of BK (Level U3.1). This paper describes the geology of this newly discovered level, along with a taphonomical analysis of the archaeological remains to better understand the assemblage formation processes. This new level was deposited at the base of LA Unit 3, in decantation facies over a point-bar. Although these facies, found throughout the site furnish ideal conditions for preservation, this is the first time in BK level U3.1 that any archaeological or paleontological remains have been found embedded within them. The taphonomic study suggests that the assemblage is the result of a short time span involving processes accumulating remains from different thanatocoenoses created over a time span of less than one year, consistent with a sedimentation process triggered by flooding of the channel during the annual heavy rains in the wet season. Furthermore, a large percentage of bones, including megafaunal remains, appear cutmarked, percussion marks and anthropgenic green fractures. Level U3.1 is the youngest level at BK, and adds to the evidence of the megafaunal exploitation behaviour of early Pleistocene hominins, which has already been extensively reported in BK Levels 4 and 5 and other African Lower Pleistocene sites.

Since the 1980s an intense scientific debate has revolved around the hunting capacities of early hominin populations and the behavioral patterns of carnivores sharing the same ecosystem, and thus competing for the same resources. This debate, commonly known as the hunter-scavenger debate, fostered the emergence of a new research line into the Bone Surface Modifications (BSMs) produced by both taphonomic agents. Throughout the following 20 years, multiple studies concerning the action of carnivores have been developed, with a particular focus on the oldest archaeological sites in East Africa. Recent technological advances applied to taphonomy have provided new insight into carnivore BSMs. A newly developed part of this work relies on Geometric Morphometrics (GMM) studies aimed at discerning carnivore agency through the morphologic characterization of tooth scores and pits. GMM studies have produced promising results, however methodological limitations are still present. This paper presents the first combined application of Machine Learning (ML) algorithms and GMM to the analysis of carnivore tooth marks, generating classification rates of 100% between carnivore species in some cases.

Lagomorph remains at Pleistocene sites may accumulate through the action of hominins, raptors or carnivores. Actualistic studies have described reliable taphonomic indicators that allow human and non-human involvement in such accumulations to be distinguished. However, discriminating between possible animal predators is not easy, because the prey remnants they leave may undergo the same kinds of taphonomic transformation. The main aim of the present work was to identify the agent, human or non-human, that accumulated the lagomorph remains at the Navalmaíllo Rock Shelter site (Pinilla del Valle, Madrid). For this, 1) established taphonomic criteria, such as anatomical representation, were taken into account, 2) the presence of infant lagomorphs was examined by determining the age of the individual animals, 3) and coprolite remains adhered to fossils were identified. This new use of the latter two criteria aided in the identification of the predator responsible for the accumulation of remains. The results suggest that this was a small carnivore, probably an Iberian lynx.

Age and sex selection of prey is an aspect of predator ecology which has been extensively studied in both temperate and African ecosystems. This dimension, along with fecundity, survival rates of prey and mortality factors other than predation are important in laying down the population dynamics of prey and have important implications in the management of species. A carnivore den located in the short-grassland ecological unit of the Serengeti was studied. Sex- and age- class (using five age categories) of the wildebeest remains recovered were analyzed through horn morphology, biometrics of the bones and tooth wear patterns. We compared our results with previous studies from lion and hyaena kills through multivariate analyses. Seasonality of the accumulation was analyzed through tooth histology. PCA and CVA results show that age class selection by predators depends on season, habitat-type, and growth rate of the wildebeest population. Female-biased predation was found to contradict classical hypotheses based on territorial male behaviour. The lion and spotted hyaena showed strong selection on age classes, contrary to previous studies. Migratory wildebeest sex ratio is regulated through differential predation by seasons and female deaths in the wet season are a trade-off for population stability. These data are crucial for an effective management of the species and the new method created may be useful for different carnivore species and their prey.

Recent excavations at FLK North (Olduvai Gorge, Tanzania) have produced new information on the orientation of archaeological materials at various levels of the site. This information includes the uniform distribution of material azimuths, which contrasts with previous inferences of highly patterned orientations of materials in the Bed I archaeological sites. Those previous inferences of patterned material orientations are based on Mary Leakey's 50-year-old drawings of artifact and fossil bone distribution, but are not verified by our precise measurements of archaeological objects made in situ. Nor do those previous results agree with the general lack of geological, geomorphological, and/or taphonomic data that would indicate significant post-depositional movement of archaeological materials in the sites. We argue here that Leakey's drawings are incomplete (only portions of each assemblage were drawn) and inaccurate in their representation of the original locations, shapes and orientations of most archaeological specimens. This argument is supported by several important mismatches in object representations between a photograph taken of a small portion of the FLK 22 Zinjanthropus site floor before the removal of the archaeological items, and the sketch of the same area drawn by Leakey. Thus, we conclude that primary orientation data of excavations (i.e., direct measurements taken from items) generated prior to object removal are the only valid indicators of the relative isotropy or anisotropy of these important paleoanthropological assemblages., Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Depto. de Prehistoria, Historia Antigua y Arqueología, Fac. de Geografía e Historia, TRUE, pub