Taphonomic Analysis Research Articles

Palaeoenvironment and taphonomy of the Hypsilophodon Bed, Lower Cretaceous Wessex Formation, Isle of Wight

The Hypsilophodon Bed occurs at the top of the Wessex Formation (Early Cretaceous, Barremian) on the Isle of Wight, southern England. Numerous remains of the small ornithopod dinosaur Hypsilophodon foxii have been recovered from the bed since the mid-nineteenth century. Previous theories for these fossil occurrences have focused on catastrophic mass death events, including miring and flood-related mortality. However, only limited sedimentological and taphonomic analyses of the horizon and its fossil assemblage have been undertaken, hindering efforts to evaluate different theories about how the assemblage formed. Here, we report a sedimentological study of the bed to constrain its depositional environment, an examination of the matrix from Hypsilophodon fossils to identify where they were collected from within the bed, and a taphonomic investigation of Hypsilophodon specimens. Our results indicate a floodplain environment, which later became a marsh and then mudflats at the edge of a lagoon. Hypsilophodon fossils are spatially and stratigraphically distributed throughout the bed. The specimens are largely incomplete and unabraded, suggesting that most perished on, or near to, the floodplain and may have lain exposed for some time prior to burial. Overall, the evidence suggests that the fossil assemblage of the Hypsilophodon Bed formed as an accumulation of remains over time.

Alternating carnivore and Neanderthal activities at Escoural Cave: insights from the taphonomic and machine learning analysis of leporid remains

Exploring the varied subsistence strategies and cave occupation patterns of Neanderthals is key to understanding their complex behaviors and ecological adaptations. Small game consumption, in particular, is considered a relevant indicator of their behavioral complexity. Rabbit assemblages from Pleistocene cave sites provide valuable insights into Neanderthal interactions with small prey and potential competition with carnivores. Here, we present the first detailed taphonomic analysis of faunal remains from Escoural Cave (Portugal), where a European rabbit (Oryctolagus cuniculus) assemblage was found alongside Middle Paleolithic stone tools and some macromammal remains. This study combines traditional zooarchaeological and taphonomic analysis of the rabbit remains with multivariate statistics and machine learning methods to establish the origin of the accumulation, and the implications for Neanderthal subsistence and cave use. Results from the taphonomic analysis show no evidence of human consumption but abundant evidence of small terrestrial carnivore activity, primarily from lynxes. This could indicate a sequential occurrence of Neanderthal and carnivore activities in the cave, with Neanderthal activities likely related to something other than rabbit consumption. Our study contributes to characterizing Iberian carnivore fossil accumulations and differentiating between faunal assemblages accumulated by carnivores and those by hominins. Additionally, we show that the use of machine learning analysis provides a robust and objective method for identifying and classifying taphonomic signatures, enhancing the accuracy and reliability of our interpretations. Future work will focus on analyzing additional faunal collections from both past and new excavations at Escoural, to test whether carnivores and Neanderthals focused on different prey types and how they shared the cave space.

Alteration by natural processes or anthropogenic manipulation? Assessing human skull breakage through machine learning algorithms

Bone breakage is one of the most common features in the archaeological record. Fractures occur at different times and are classified as fresh or dry depending on the presence or absence of collagen in the bone. In the study of human remains, the timing of the occurrence of a fracture is of crucial importance as it can sometimes be linked to the cause of death. Types of skull breakage can be classified based on when they occurred, though not all fractures correspond to the expected features. This variability is added to the challenge of working with bones covered in consolidant, which obstructs the bone surface and hinders taphonomic analysis. This is the case of the Txispiri calotte, which was categorized as a skull cup in the early 20th century, though this classification was later rejected in the 1990s. In this study, we used statistics and machine learning (ML) to test the breakage characteristics of one set of skull fragments with fresh fractures, another set with dry fractures, and the Txispiri calotte. For this purpose, we considered the fracture type, trajectory, angles, cortical delamination and texture of each of the individual fractures. Our results show that the 13 fractures of the Txispiri calotte correspond to dry breakage and bear no relation to artificially produced skull cups. This study shows the potential of ML algorithms to classify fresh and dry fractures within the same specimen, a method that can be applied to other assemblages with similar characteristics.

From the wetlands to the farmyard: Osteometric approach to the presence of domestic geese and ducks in Zuid Holland, 150–1700 AD

AbstractThe history of domestic ducks (Anas platyrhynchos domesticus) and domestic greylag geese (Anser anser domesticus) remains poorly understood. This is mainly caused by the difficulty of identifying archaeological bones as domestic due to the existing overlap in sizes. A recently published osteometrical methodology is applied that successfully allows to identify domestic forms and distinguish between anatid species with more confidence. Four archaeological assemblages from the Zuid Holland province in the Netherlands are reanalyzed, ranging from the Roman period to the 17th century AD.It is determined that domestic geese were present in the Netherlands since at least 160–230 AD and domestic ducks since at least 585–725 AD. The latter might also be present in the Roman assemblage, but the evidence is inconclusive. Domestic species constitute only a small percentage of the total consumed anatids and do not surpass 15%–20% in any case, which is mainly caused by the weight of wildfowling in the Netherlands. Chickens (Gallus gallus domesticus) were therefore much more prevalent than domestic anatids in all assemblages. Taphonomical analysis did not show substantial differences between wild and domestic anatids. The sample size considered in this project is likely too small and biased to accurately detect any kind of evolution through time.

Artificial intelligence for the identification of taphonomic bio-accumulator agents: an actualistic test of potential faunal accumulation agency applied to Tritons Cave (Lleida, Spain)

Studying bone surface modifications (BSMs) in neotaphonomic research is an important aid to reconstruct agency in the archaeological and palaeontological record. The significance of correctly identifying BSMs has led to extensive debates about adequate methodological and interpretive frameworks to identify taphonomic agents and their bone-modifying patterns in dynamic taphonomic processes; especially those involving inter-agency interactions. Recent analytical innovations in the field have given rise to more updated and less biasing methods, including those rooted in multivariate statistics and artificial intelligence algorithms. Among the latter, convolutional neural networks have demonstrated a substantial potential in precision in the identification and characterization of BSMs. In this study, we present a successful application of these methods to reconstructing taphonomic agency in an archaeological context, specifically in Unit 2 of Tritons Cave (Lleida, Spain). Previous interpretations of this palaeontological layer suggested that it was a natural palimpsest created by carnivores, namely leopards. Through the present research, we objectively tested the original felid-accumulation hypothesis associated with the site’s original taphonomic analysis. Our findings provide additional evidence of the primary leopard agency in the formation of the assemblage and underscores the significant potential of transfer learning for identifying taxon-specific carnivore agency.

Holocene hillslope evolution through extreme rainfall induced landslides in the mountainous region of Rio de Janeiro, Brazil: Geochronology and paleoenvironmental evidence

AbstractGeomorphological, geochronological and paleoenvironmental data were integrated to examine how Holocene environmental changes have influenced geomorphic responses, particularly recurrent landslides and colluvial deposition on the steep slopes of the Rio de Janeiro mountains. This study focuses on a pilot hillslope (32°) with a concave‐up topographic hollow and associated shallow translational landslides, enhancing our understanding of how extreme climatic events shaped landscape evolution in the region prior to significant human impact. Recently, the hillslope was reactivated by a shallow landslide triggered by the extreme rainfall event of January 2011, which resulted in over 3600 landslides in the region. Subsequent deep gullying exposed a deposit (>3 m) containing buried, organic‐rich colluvial layers. Comprehensive analysis was conducted on sedimentological, geochronological (AMS 14C), palynological, taphonomic and carbon isotope (δ13C) data from this deposit. The geochronological results indicate that the hillslope's evolution involves recurrent shallow translational landslides throughout the Holocene, with organic colluvial layers dating from 10 148 cal years BP at the base to 663 cal years BP at the top. Charcoal fragments of various sizes suggest frequent paleofires during the Holocene. Palynological and taphonomic analyses reveal post‐fire herbaceous‐shrubby vegetation and ferns (Asteraceae, Poaceae, Alchornea, Baccharis, Celtis and Polypodium), with predominant pollen grains and spores showing mechanical damage indicative of high transport energy and physical stress conditions. The rarefied post‐fire vegetation and pioneer forest genera identified in the deposit are associated with a hydrological and mechanical dynamics that likely created less stable conditions on the slope system, promoting the occurrence of shallow landslides throughout the Holocene.

An Upper Paleolithic horse mandible with an embedded lithic projectile: Insights into 16,500 cal BP hunting strategies through a unique case of bone injury from Cantabrian Spain

AbstractEmbedded artifacts in osteoarchaeological remains may be key to approaching hunting strategies and other behavioral‐related issues such as technological development. However, that kind of evidence is not common within the archaeological record and often not well‐characterized, especially for faunal remains from prehistoric sites. Here, we present and discuss a unique case of a horse (Equus caballus) mandible with an embedded lithic remains from the Upper Paleolithic (ca. 17,300–16,200 cal BP) from La Garma cave in Cantabria, Spain. Our macro‐ and microscopic faunal and lithic integrated analysis suggests that the case presented here is a potential perimortem hunting lesion, representing an uncommon hunting strategy during the Magdalenian period. Furthermore, this study, representing the first case of its kind in the Iberian Peninsula, emphasizes the importance of the taphonomic analysis of bone surfaces to approach the understanding of past human behaviors.

Morphology and taphonomy of the gastropod Terebralia palustris from an iron age site in the Arabian Peninsula

The Indo-Pacific gastropod Terebralia palustris is particularly suitable for comparing natural and anthropogenic induced taphonomic pathways due to its wide geographic distribution and common presence within archeological context. The present study aims to (1) correlate shell architecture and morphology with fragmentation pattern and preservation, (2) quantify taphonomic changes to differentiate between natural vs. anthropogenic preservation features, (3) provide a guideline for analyzing fragmented shell remains in archeological material. Shells and taphonomic features were studied from both recent mangrove environments from the Emirate of Sharjah, United Arab Emirates as well as archeological material within the Iron age II site (1000–600 BC) of Muweilah near the City of Sharjah. Techniques utilized include morphometry, thin sectioning, scanning electron microscopy (SEM) of recent specimens and a semi—quantitative taphonomic analysis of anthropogenic material. Thin sectioning shows a complex internal shell morphology with a tripartite subdivision of shell layers. The recent material shows better preserved features on both the exterior and internal shell surfaces than the highly fragmented material recovered from the archeological context, which shows a distinct size distribution as well as showing higher levels of surface abrasion, surface cracks and color alterations. These features are correlated to extraction techniques, cooking methods and waste disposal handling.

Taphonomy and taphofacies of the bioclastic accumulations of Baía Formosa Paleolagoon (Quaternary), Rio de Janeiro state, Brazil

The study of taphofacies is extremely relevant in Paleontology as it provides support for paleoenvironmental interpretation by associating the preservation state of fossil content with sedimentological and stratigraphic characteristics. Despite its importance, there are few analyses of taphofacies in bioclastic accumulations of invertebrates in Brazilian sedimentary basins or Quaternary sedimentary accumulations. Therefore, this article aims to identify taphofacies in Holocene bioclastic accumulations distributed along the coastal plains of Armação de Búzios, Rio de Janeiro State, Brazil. After qualitative observations and taphonomic analysis of material from two outcrops located in the Canal Marina Porto Búzios, three distinct taphofacies were identified. Taphofacies 1 was interpreted as a beach environment related to strandlines; taphofacies 2 was interpreted as a shallow lagoon environment; and taphofacies 3 was interpreted as a lagoon margin. The taphofacies identified in this study are related to the maximum Holocene transgression, which occurred in the region about 6000 years BP, and the subsequent marine regression. This study presents relevant and unprecedented data, enabling a better understanding of the coastal evolution of Armação dos Búzios and Cabo Frio.

Taphonomic and zooarchaeological analysis of fauna from the Howiesons Poort and post-Howiesons Poort at Klasies River main site: Examining links between the environment and subsistence behaviour in Marine Isotope Stages 4 and 3

Marine Isotope Stages (MIS) 4 and 3 were significant periods encompassing some 50,000 years, including at least two techno-cultural entities: the Howiesons Poort (HP) and post-HP. Exploring subsistence and environmental changes during these periods may help us understand broader aspects of behavioural and occupational patterns over MIS 4 and 3. In this paper, we report on taphonomic analyses of a sample of early HP, late HP and post-HP fauna from Klasies River main site cave 1A. We use these and other faunal data to examine the links between subsistence behaviour and the environment during the HP and post-HP. The results of our analyses indicate that percussion marks are abundant in the HP, with percussion mark frequencies more prevalent in the later HP than the early HP indicating that humans were the primary accumulators of fauna in the HP. Other taphonomic data such as fracture patterns, burning and trampling marks also suggests that human activity was more prevalent in the HP than the post-HP. In contrast, in the post-HP, the prevalence of zoogenic marks on small mammal remains, and comparisons to actualistic assemblages indicate that carnivores probably contributed significantly to the post-HP assemblage. In all the samples investigated, crania dominate skeletal-part profiles. This could be a result of taphonomic bias, or it could indicate that foraging likely occurred relatively close to the site. Analyses of carcass-part utility show that marrow-extraction may have been a key subsistence strategy in the HP. In the post-HP, bone density-mediated attrition had a significant effect on fauna making it challenging to ascertain subsistence patterns, but preliminary analysis may also suggest marrow extraction in combination with other strategies.Post-depositional taphonomic marks such as manganese staining suggest that post-HP and late HP deposits were significantly more affected by moisture than the early HP deposits. Previous investigations of large mammal data point to more closed environments in the early HP, while our data indicate that the environment in the late HP and post-HP was largely similar. In comparing our data to previously analysed micromammal proxy data, we show that major environmental changes at KRM occurred after the shift to post-HP lithic technology. However, the taphonomic data suggests a close relationship between changing subsistence strategies and the MIS4/3 transition.

Animal exploitation by the last hunter-gatherers in the Mediterranean Iberia. New data from the Mesolithic groups from Cocina cave (Valencia, Eastern Iberia)

Mesolithic groups in Mediterranean Iberia lived during a period of bioclimatic and cultural changes. Thus, their economic behaviour and the availability of plant and animal resources show some interesting variation compared to previous periods that indicate changes in mobility patterns and social connectivity networks. This paper presents information on patterns of animal exploitation of the last hunter-gatherers in this region through zooarchaeological and taphonomic analyses of faunal remains from one of the key sites of the Iberian Peninsular Mesolithic, Cocina cave. This site is located in a mountainous woodland region with a rich Late Mesolithic archaeological record. Results indicate that Iberian ibex, red deer, and rabbits were the most hunted species, but that a diversity of other taxa were also present. The comparison to other Mediterranean sites suggests that Late Mesolithic foragers had common animal exploitation patterns with an increased taxonomic diversification and a clear connection to coastal areas. We suggest these foragers practiced a logistic pattern of food procurement, combining long-term with short-term camps including hunting spots, and in some cases evidence for broad scale social interactions. We hypothesize that Cocina cave may have served as a nexus of social and subsistence activities.

Unraveling the interplay between humans and carnivores in El Olivo Cave during the Middle and Upper Paleolithic period (Llanera, Asturias, Spain)

El Olivo Cave (Llanera, Asturias, Spain) is a small karst cave within the Aboño River watershed. It holds a significant archaeological and paleontological record dating from the Middle and late Upper Paleolithic, featuring several lithic artifacts and faunal remains in each archaeological level. The study of the faunal remains reveals a high representation of ungulates, with Cervus elaphus and Equus ferus being the main ones. Carnivores are also represented by diverse species such as Vulpes vulpes and Canis lupus, among others. The taphonomic analysis evidenced the presence of human activity, accompanied by a significant incidence of tooth marks across all stratigraphic units and water-related processes in the lower part of the sequence. During this temporal range, there were faunal accumulations of anthropogenic origin altered by the action of other agents, especially carnivores. A diverse array of carnivore used the same space and taking advanced of the anthropogenic residues as scavengers. Moreover, we suggest a commensal synanthropic behavior exhibited by foxes. Consequently, El Olivo Cave is an illustrative case to explore the carnivore action in levels with human presence, something unusual at the late Upper Paleolithic sites in Northern Iberia.

Violent death of a warrior in the destruction of Roca Vecchia, Apulia, Italy: Insights on hostilities and Aegean connections in the Bronze Age

This study recreates aspects of the life and death of a young adult male who died during the siege of Roca Vecchia, a Bronze Age fortified coastal site in Italy. The partially charred and unburied individual, Roca US813A, was found among the debris in the southern room of the main gate to the city.This paper highlights information that can be retrieved from a single partially preserved skeleton. Detailed bioarchaeological, forensic, and taphonomic analysis, and thorough examination of archaeological and contextual data permit an osteobiography of this individual to be developed, which we situate in the overall picture of Middle Bronze Age regional events and exchanges between Italy and the Aegean world.This individual represents a unique example of information derived from bones from an archaeological context. After suffering fatal blows to the body, the individual was accidently exposed to heat. This allowed us to analyze wounds that had undergone thermal alteration. Since the combustion of the body was only partial and the same bone retains both highly burned and unburned parts, we were able to document the variations induced by heat at a macroscopic and microscopic level.To investigate the circumstances of his death, we focus on macroscopic and microscopic details of taphonomy and trauma using micro-CT, forensic, and multi-isotopic analysis. This may be the first secure evidence of a Middle Bronze Age (MBA) war casualty in Italy. In addition to detailed information about their manner of death, we discuss implications for the peopling of the site, tactics in Bronze Age warfare, and the nature of relations between Roca and the Aegean region.

Neanderthal resilience and adaptability: insights from the Abric Pizarro faunal assemblage during the MIS 4

The examination of faunal assemblages through zooarchaeological analyses constitutes a fundamental approach for gaining insight into the intricate behaviours of Neanderthals. Previous investigations have primarily focused on periods of relative environmental stability, and this has provided a wealth of relevant archaeological data. However, our understanding of Neanderthal resilience during the MIS 4, a period presumably characterised by harsh environmental conditions, remains limited. This study presents the first comprehensive analysis of the faunal assemblages from Levels M and P at Abric Pizarro. The geographic location of Abric Pizarro in the southeast Pre-Pyrenees, combined with chronometric dating, offers a unique opportunity to explore Neanderthal behaviours during a poorly known chronological period. The detailed zooarchaeological analysis comprised taxonomic identification, taphonomic analysis and age-at-death profiling to explore the adaptability and flexibility in the Neanderthal diet. The findings indicate that Neanderthal groups incorporated a diverse range of protein resources from small herbivores (e.g., caprids) to very large herbivores (e.g., Bos/Bison). These results not only demonstrate an adaptability to changing environments in an area traditionally deemed unsuitable for long-term occupation, but also contributes significantly to our understanding of the complex behaviours exhibited by Neanderthals.

Evolving landscape and cultural change during the Middle Palaeolithic in Southeast Zagros (Iran): Insights from a micromammal assemblage

The Iranian Zagros is a remarkable zone to study Middle and Upper Palaeolithic human occupations and Tang-e Shikan (Arsanjan) is a strategic cave site which archaeological evidence can be taken as a proxy for the southeast portion. Micromammals have been extensively used as palaeoecological indicators and here we use the assemblage from Tang-e Shikan to infer the landscape and environment that framed and arguably triggered cultural change. A thorough taphonomic analysis was undertaken prior to any interpretation. Fourteen taxa have been identified: two “insectivores” s.l., nine rodents, two lagomorphs, and unidentified chiropterans. The remains would be the digestion by-products of a category 5 opportunistic predator: either an avian raptor or a mammalian carnivore. Our results show that shrubland and grassland dominated the distribution of habitats in the area during the Middle Palaeolithic (MP), followed by moderate rocky, desert, and steppe components, and sparse patches of woodland. The younger period of the MP occupation (NMP: ∼55-45 ka BP) would be somewhat wetter than the older period (OMP: ∼70-55 ka BP). Within a general environmental stability, slight changes between OMP and NMP are reasonably correlated with a shift in certain cultural patterns, as the use of a water reservoir and a stone drainage system during the OMP or the increase of hunting and moderate change in lithic technology and raw material acquisition during the NMP. Our environmental inferences are further supported by palynological data and match a regional trend towards wetter habitats in moving from the MP to the present.

Climatic variability in the Armenian Highlands as the backdrop to hominin population dynamics 50–25 ka

The impact of Late Pleistocene climatic oscillations, volcanism and the diverse terrain of the Armenian Highlands affected hominin population dynamics and movements through the region. To test different scenarios for the period 50–25 ka regarding expansion, adaptive response, intra-population interactions and extinction, we need local on-site paleoclimatic data found in association with hominin occupations. However, this approach has been hampered by the dearth and highly uneven spatiotemporal recovery of paleoclimatic data from prehistoric sites across the region. In this study, we analyze multiple assemblages of fossil micromammals from the Late Middle Paleolithic (LMP) Lusakert-1 rockshelter (two fossil-yielding strata; <55 ka) and Early Upper Paleolithic (EUP) Aghitu-3 Cave (four fossil-yielding strata; ∼39–24 ka) using geometric morphometric-aided taxonomy, to quantify the representation of different species among the abundant and diverse arvicoline genera (Microtus and Chionomys; mean = 58% of assemblages). We combined this approach with quantitative species-level paleoclimatic reconstructions (Bioclimatic Model; 14 rodent taxa) to determine changes in habitat composition as well as temperature and precipitation shifts during the Late Middle–Early Upper Paleolithic. Taphonomic analysis was conducted to establish isotaphonomy among the assemblages. The analysis shows higher than present-day absolute temperatures for the series of occupations at both Lusakert-1 and Aghitu-3, making it unlikely that hominin activity at the sites coincided with extreme cold-climate phases. A multivariate comparison of the taxonomic abundances (genus level) across a wider sample of regional Middle Paleolithic (MP) and Upper Paleolithic (UP) cave sites (Hovk-1, Kudaro-1, Mezmaiskaya, Satsurblia and Dzudzuana) indicates the possibility of cold-period occupation at only two of the sites, Mezmaiskaya Layers 3 and 2 and Kudaro-1 Layer 3. We surmise that the manufacturers of LMP lithic industries in the Caucasus were well adapted to these challenging environments, thus undermining arguments that rapid climate change through the LMP/EUP period could alone have determined the course of population dynamics in this region.

Fate and preservation of the late pleistocene cave bears from Niedźwiedzia Cave in Poland, through taphonomy, pathology, and geochemistry

This comprehensive study examines fossil remains from Niedźwiedzia Cave in the Eastern Sudetes, offering detailed insights into the palaeobiology and adversities encountered by the Pleistocene cave bear Ursus spelaeus ingressus. Emphasising habitual cave use for hibernation and a primarily herbivorous diet, the findings attribute mortality to resource scarcity during hibernation and habitat fragmentation amid climate shifts. Taphonomic analysis indicates that the cave was extensively used by successive generations of bears, virtually unexposed to the impact of predators. The study also reveals that alkaline conditions developed in the cave during the post-depositional taphonomic processes. Mortality patterns, notably among juveniles, imply dwindling resources, indicative of environmental instability. Skeletal examination reveals a high incidence of forelimb fractures, indicating risks during activities like digging or confrontations. Palaeopathological evidence unveils vulnerabilities to tuberculosis, abscesses, rickets, and injuries, elucidating mobility challenges. The cave’s silts exhibit a high zinc concentration, potentially derived from successive bear generations consuming zinc-rich plants. This study illuminates the lives of late cave bears, elucidating unique environmental hurdles faced near their species’ end.

Multidisciplinary analyses of partial human remains discovered in the Caribbean Sea (Venezuela)

ABSTRACT In March 2022, human remains were discovered submerged 15 metres underwater, near Cubagua Island, Venezuela. The remains were intricately entangled and secured to the seafloor. The investigation was conducted by the Servicio Nacional de Medicina y Ciencias Forenses (SENAMECF) of Venezuela, and it involved an underwater recovery operation, followed by a comprehensive examination. The medicolegal, anthropological, odontological, and taphonomical analyses alongside diatom test were conducted to ascertain the identity of the remains, determine the cause of death, and estimate the post-mortem interval (PMI)/post-mortem submersion interval (PMSI). Collaborative efforts with international experts on adipocere and barnacle analyses allowed for the refinement of the enhanced the precision of information provided in plea announcements, which facilitated the identification of the subject. Forensic analyses on incomplete and highly decomposed human remains present inherent complexities, which are exacerbated in underwater environments. Compounded by the limited experience and expertise in aquatic forensics among law enforcement agencies worldwide, the present case exemplifies a successful professional collaboration that surmounted a diverse array of challenges. This case underscores the critical importance of knowledge-sharing within the continuously evolving field of forensic science, serves as an illustrative example, and provides guidelines for the investigation of similar cases in the future.

Archaeological evidence of rodent consumption in North Africa: The Middle Stone Age of the rock shelter Ifri n'ammar in northeastern Morocco

This study presents undeniable evidence of anthropogenic exploitation of small mammals in Ifri n'Ammar rock shelter, located in the northeast of Morocco. Among the rodent species found at this site, Ctenodactylus gundi predominates in the assemblage of small mammals between approximately 130 ± 8 ka and 83 ± 6 ka. The taphonomic analysis of the fossil remains of this species, discovered alongside other components of the archaeological assemblage, clearly indicates that during the Middle Stone Age (MSA), humans consumed this species. Therefore, they are considered the main agents responsible for the accumulation of dental and postcranial remains of this species recorded in the shelter. Since the early Upper Pleistocene, bone elements bearing cut-marks and burn traces unequivocally attest to the consumption of this rodent by the hunter-gatherers at the Ifri n'Ammar rock shelter. Our findings regarding the exploitation of this species by humans in the northeastern region of Morocco are corroborated by ethnographic data, demonstrating that North African populations captured and consumed this large-sized rodent until the last century. The species Ctenodactylus gundi is known for its diurnal activity, gregarious and social habits, as well as its preference for rocky and arid environments.

Taphonomy and paleohistology of a dinosaur rib from Marília Formation, Bauru Group, in the state of Minas Gerais, Brazil

The Bauru Group (Campanian–Maastrichtian) has one of the richest fossil records of Cretaceous in South America. All dinosaur fossils from this unit were assigned to Saurischia, most of them poorly preserved. We present the histological and taphonomic analysis of a dinosaur dorsal rib fragment from the Marília Formation in the western state of Minas Gerais. Thin sections were prepared to describe the microstructures of the bone tissue and the fossilization processes involved in preserving the specimen. An elemental analysis was also performed to verify the chemical composition of the fossil and rock matrix. Haversian bone was identified in the rib cortex, and no growth marks or an external fundamental system were found. The rib probably belonged to a saurischian dinosaur because of its plank shape and elliptical cross-section. Hypotheses regarding taphonomic processes were inferred. An extended period of subaerial exposure, followed by high-energy transport, was interpreted due to extensive fractures and signs of abrasion on the outer surface of the bone. Pyrite pseudomorphs (framboids) indicate that the bone was deposited in a reductive environment. After burial, the rapid precipitation of calcite and alkaline stability allowed the preservation of apatite during the recrystallization phase. The manganese hydroxides were deposited on apatite crystals during early diagenesis. We concluded that the fossil rib presented a common taphonomic bias identified among vertebrate fossils of the Bauru Group, which is associated with the exposure of the bones to arid and semiarid climates, their transport into the depositional environments and pedogenetic influence during fossil diagenesis.