Tooth Marks Research Articles

Evidence of age segregation behavior in Hypacrosaurus stebingeri (Hadrosauridae: Lambeosaurinae) based on the taphonomic comparison of bonebeds from the Upper Cretaceous (upper Campanian) Oldman Formation of southernmost Alberta (Canada) and Two Medicine Formation of Montana (USA)

Hadrosaurid social structure is still poorly understood. Evidence from bonebeds suggests that juvenile individuals of some hadrosaurid species lived apart from herds composed of older individuals, a phenomenon called age segregation. However, the timing at which juvenile individuals became segregated and later rejoined a multigenerational herd is unknown. Three monodominant bonebeds that preserve the remains of multiple individuals of the lambeosaurine hadrosaurid Hypacrosaurus stebingeri at different ontogenetic stages offer an opportunity to better understand the social structure of this species: the Devil's Coulee juvenile hadrosaur bonebed (JBB) from the Oldman Formation of Alberta (Canada) preserves a minimum of four similar-sized late juvenile individuals; the Blacktail Creek North (BCNB) bonebed from the Two Medicine Formation of Montana (USA) preserves a minimum of 23 early juvenile (previously referred to as “nestling”) individuals; and the Lambeosite (LB) bonebed preserves four similar-sized late juvenile individuals and one adult individual. These bonebeds show uniform taphonomic signatures throughout their respective bone assemblages, characterized by little to no weathering and abrasion, uniform style of fracturing, and rare tooth marks on bones. All three bonebeds are interpreted as mass-mortality assemblages. Histological data indicate that the late juvenile individuals from the JBB were three years old at the time of death, similar to the slightly larger late juvenile individuals from the LB, whereas the early juveniles from the BCNB had not yet reached 1 year of age. A taphonomic comparison of the three bonebeds reveal that H. stebingeri individuals lived in age-segregated groups, likely cohorts, until into their fourth year of life when, after having reached sexual maturity, they rejoined a multigenerational herd. The smaller number of individuals preserved in bonebeds representing later ontogenetic stages could reflect a decrease in group size due to high juvenile mortality rate or to higher metabolic needs.

Who is who and why. Implications of tooth-marks identification at two sites in the Orce Basin Archaeological Zone (OBAZ; southern Spain)

The Orce Basin Archaeological Zone (OBAZ; Granada, Spain) is well known because it contains some of the most important Early Pleistocene archaeo-palaeontological sites for understanding the earliest human settlement in the westernmost part of Eurasia and its ecological context. Among those are Venta Micena (VM), Barranco León (BL) and Fuente Nueva 3 (FN3). The role played by the extinct Pachycrocuta brevirostris present at the OBAZ sites has long been recognised in the literature. However, little or nothing is known about the agency of the other documented carnivore species. Nevertheless, the development of technologies such as 3D modelling, geometric morphometrics, robust data modelling and artificial intelligence algorithms makes it possible to characterise a type of tooth mark (pits) and its assignment to a taxon. Moreover, such a combination of methodologies allows us to infer novel aspects related to the behaviour of carnivores, to establish interpretative differentiation between the carnivore agents at VM3 and BL, to point to the interactions among them and with Homo, and to review some proposals on the first human dispersal outside Africa.

Study on ballast test of underwater pile gripper

Abstract The underwater pile gripper plays an important role in the installation of the offshore jacket platform. With the further development of offshore oil, it is gradually moving into deep water. Therefore, people pay more attention to the reliability test of pile grippers. The Gripper of underwater pile gripper is the key component of the supporting pipe pile, which determines the quality of the underwater pile gripper to a great extent. Two sets of underwater pile grippers are made of imported and domestic materials, respectively. The maximum loading capacity is 600 tons. The pile gripper is clamped on the test steel pile, and the load is applied by the hydraulic ballast machine. After the experiment is completed, whether the scratch of the tooth mark of the gripper exceeds the expected amount is detected, so as to prove the clamping performance of the pile gripper. The results show that all the components of the pile gripper are not damaged, the hydraulic components are not leaking, the teeth of the imported material gripper and the domestic material gripper are all intact after testing, and the maximum width of tooth marks on steel piles of the two kinds of grippers is about 4 mm and 5 mm, respectively, less than the requirement of 10 mm. The pile gripper made in China can meet the requirements of the actual project for the holding performance, and the holding effect is good.

Experimental study on anti-clamping damage structure of drill pipe against slip-crushing

Deep ground conditions bring higher challenges to drill pipe and slip tools, and the slip is more likely to seriously bite or crush the drill pipe, which will easily lead to failure of the drill pipe, seriously affecting the safety of drilling operations. Based on the theoretical analysis of the mechanical behavior and damage characteristics of the drill pipe held by slips, the deep ground suitability test of API-S135 conventional drill pipe and S135 and V150 anti-slip crushing drill pipe combined with micro-teeth marks hydraulic slips with thickened slip holding area is carried out. The test results show that: Compared with S135 common drill pipe, S135 and V150 anti-slip crushing drill pipe have an average change in outside diameter of 43% and 0.19%, with a reduction of 8.31% and 4.9% in the proportion of the maximum depth of the tooth mark, both of which have good mechanical resistance to slip crushing and biting, and the tensile load capacity of the clamped pipe body has been significantly improved. Combined with micro-tooth mark slips, the slips in deep drilling operations can tighten the drill pipe and make the bite damage of the drill pipe less. It can effectively ensure the safety and efficiency of deep drilling operations.

The late Early Pleistocene site of Fuente Nueva-3 (Guadix-Baza Depression, SE Spain): a hyena latrine developed on a quicksand trap for megaherbivores?

AbstractThe late Early Pleistocene archaeological site of Fuente Nueva-3 (FN3), which lies in the Guadix-Baza Depression (SE Spain) and is dated to ~ 1.4 Ma, contributes some of the oldest evidence of hominin presence in Western Europe, including a huge tool assemblage of Oldowan tradition, manuports (i.e., unmodified stones used as percussion tools) and abundant fossils of large mammals, some of which preserve anthropogenic marks related to defleshing, butchering and marrow processing. In addition, there are bones with tooth marks produced by scavenging carnivores. The fertile layers of the FN3 section have been grouped in a lower archaeological level (LAL) and an upper archaeological level (UAL). Both levels preserve abundant skeletal remains and lithic tools. However, the LAL shows a high density of manuports, which suggests that hominin activity was more intense at this level, while the UAL preserves many remains of megaherbivores, particularly proboscideans (Mammuthus meridionalis), and almost all coprolites unearthed from the site, which points to a greater involvement of the giant hyenas (Pachycrocuta brevirostris). In this paper, we (i) test for statistical differences in the composition of the faunal assemblages preserved in the UAL and LAL; and (ii) analyze particle size in the fertile layers of both archaeological levels. Our results show that megaherbivores are comparatively overrepresented in the UAL, specially by young elephants, while other medium-to-large and large-sized ungulates, particularly equids, are more abundant in the LAL, showing a predominance of adult individuals. Concerning the sedimentology, layers 2–3 of the LAL show a predominance of silts and clays, with sands representing a minor fraction. In contrast, layer 5 of the UAL is composed of two-thirds of fine and very fine sands, with the remaining third consisting of silts and clays. These data and the paleoenvironmental reconstruction of layer 5 suggest that it may be interpreted as a paleo-quicksand in which megaherbivores were trapped due to the elevated weight per unit area supported by their feet, and their half-sunken carcasses attracted the scavengers, particularly the hyenas, which fed on these carcasses and defecated in their surroundings.

Lynxes and foxes among hyenas, bears and humans. Unit 3 of the Cova del coll Verdaguer Upper Pleistocene site (Barcelona, Iberian Peninsula)

Zooarchaeological and palaeontological assemblages, especially those located in karst cavities, are usually the product of the activity of several taphonomic biological agents. This is also the case of the Upper Pleistocene site of Cova del Coll Verdaguer (Barcelona, Iberian Peninsula), where hyenas accumulated most of the ungulates, bears used the cave to hibernate and for birthing cubs, and humans occasionally visited the cave. The main aim of this study is to investigate the role played by medium-sized mammalian carnivores in the formation of Unit 3 (the Sala Sal de Llop chamber). For this purpose, we analysed Lynx pardinus and Vulpes vulpes remains, on the one hand, and leporid remains, on the other, applying different taphonomic (breakage and surface modifications) zooarchaeological (skeletal parts frequencies, age at death) and spatial methods (GIS, geostatistics, refits). Regarding medium-sized carnivores, the results indicate a predominance of adult individuals, a fairly complete anatomical representation (especially in the case of the lynx), the refitting of several elements (in the case of the lynx, many of them clustered in the same area), and the presence of tooth marks on some remains. This data points to the natural death of these animals inside the cave, and suggests they were subsequently scavenged by other carnivores. With respect to leporids, adult individuals predominate, the most abundant elements are innominate bones and those from the distal segment of the appendicular skeleton, and there is evidence of carnivore damage on several remains. In accordance with these results, the leporid assemblage is interpreted mainly as a non-ingested assemblage caused by the feeding activity of the Iberian lynx and, to a lesser extent, the red fox. Thus, the combination of all these analyses indicates that the medium-sized terrestrial carnivores did not play a merely passive role, but were also accumulators and modifying agents, at least in terms of the leporid remains. Although ungulates are not the focus of this study, we have also discussed the potential role of Iberian lynx and red fox in accumulating and modifying them. This work adds to previously published studies indicating that Cova del Coll Verdaguer is the product of mixed occupations of different carnivore taxa, suggesting that lynxes and foxes used the cave as a safe place to rest, transport their prey and consume it. Therefore, this study will shed more light on the relationships between human groups and different carnivore taxa at Cova del Coll Verdaguer and, by extension, in the European Upper Pleistocene, demonstrating that the study of fossil collections can contribute significantly towards extending our knowledge on past carnivore and human behaviour.

Thermal radiation of tongue surface as a human computer interaction diagnostics technique based on image classification with software interface

Backgroundand Purpose: Thermal radiation plays a pivotal role in addressing recognition limitations encountered by traditional Chinese medicine's tongue diagnosis. Modern thermal radiation diagnostic instruments offer enhanced objectivity, and in this study, we strive to further improve the diagnostic process through the integration of Human-Computer Interaction (HCI) principles. Our objective is to introduce the thermal radiation DenseNet ensemble model, synergizing the strengths of Convolutional Neural Networks (CNNs) and HCI principles to advance tongue image recognition in healthcare. This approach aims to enhance classification accuracy, even when faced with limited training data. MethodologyTransfer learning, utilizing fine-tuned CNNs and DenseNet, is employed for precise classification, with a specific focus on distinguishing tooth-marked tongues. A portable hand-held thermal radiation diagnostic instrument, seamlessly integrated with HCI, is developed for both clinical use and research. Experimental resultsMeticulously curated datasets, formed through the annotation of thermal radiation images, confirm the superior performance of the DenseNet architecture in tooth mark and tongue feature recognition. The proposed tooth mark tongue recognition model exhibits a significant accuracy improvement of approximately 25% compared to similar tasks in existing studies. Additionally, an AI health detector tailored for Traditional Chinese Medicine (TCM) thermal radiation image recognition is introduced, showcasing the seamless integration of HCI principles into healthcare applications. This innovative tool not only assesses users' health but also provides personalized health recommendations, illustrating the transformative potential of combining technology and healthcare. Discussion and conclusionIn addressing the limitations of traditional tongue diagnosis, thermal radiation emerges as a key factor enhancing objectivity and accuracy. The thermal radiation DenseNet ensemble model, along with HCI integration through the portable hand-held device, proves effective for improved TCM thermal radiation image identification in healthcare. The fusion of technology and HCI principles underscores the potential to elevate health assessments and offer valuable guidance to users.

Computer vision enables taxon-specific identification of African carnivore tooth marks on bone

Taphonomic works aim at discovering how paleontological and archaeofaunal assemblages were formed. They also aim at determining how hominin fossils were preserved or destroyed. Hominins and other mammal carnivores have been co-evolving, at least during the past two million years, and their potential interactions determined the evolution of human behavior. In order to understand all this, taxon-specific carnivore agency must be effectively identified in the fossil record. Until now, taphonomists have been able to determine, to some degree, hominin and carnivore inputs in site formation, and their interactions in the modification of part of those assemblages. However, the inability to determine agency more specifically has hampered the development of taphonomic research, whose methods are virtually identical to those used several decades ago (lagged by a high degree of subjectivity). A call for more objective and agent-specific methods would be a major contribution to the advancement of taphonomic research. Here, we present one of these advances. The use of computer vision (CV) on a large data set of images of tooth marks has enabled the objective discrimination of taxon-specific carnivore agency up to 88% of the testing sample. We highlight the significance of this method in an interdisciplinary interplay between traditional taphonomic-paleontological analysis and artificial intelligence-based computer science. The new questions that can be addressed with this will certainly bring important changes to several ideas on important aspects of the human evolutionary process.

Tongue feature dataset construction and real-time detection.

Tongue diagnosis in traditional Chinese medicine (TCM) provides clinically important, objective evidence from direct observation of specific features that assist with diagnosis. However, the current interpretation of tongue features requires a significant amount of manpower and time. TCM physicians may have different interpretations of features displayed by the same tongue. An automated interpretation system that interprets tongue features would expedite the interpretation process and yield more consistent results. This study applied deep learning visualization to tongue diagnosis. After collecting tongue images and corresponding interpretation reports by TCM physicians in a single teaching hospital, various tongue features such as fissures, tooth marks, and different types of coatings were annotated manually with rectangles. These annotated data and images were used to train a deep learning object detection model. Upon completion of training, the position of each tongue feature was dynamically marked. A large high-quality manually annotated tongue feature dataset was constructed and analyzed. A detection model was trained with average precision (AP) 47.67%, 58.94%, 71.25% and 59.78% for fissures, tooth marks, thick and yellow coatings, respectively. At over 40 frames per second on a NVIDIA GeForce GTX 1060, the model was capable of detecting tongue features from any viewpoint in real time. This study constructed a tongue feature dataset and trained a deep learning object detection model to locate tongue features in real time. The model provided interpretability and intuitiveness that are often lacking in general neural network models and implies good feasibility for clinical application.

Coexistence of Indian Pangolin Manis crassicaudata (Geoffroy, 1803) (Mammalia: Pholidota: Manidae) and Indian Crested Porcupine Hystrix indica (Kerr, 1792) (Mammalia: Rodentia: Hystricidae) in Purulia District, West Bengal, India

The Indian Pangolin Manis crassicaudata and the Indian Crested Porcupine Hystrix indica are subject to extensive poaching in Purulia District (West Bengal, India), diminishing their populations, and making the study difficult. Applying methodologies that include local sightings, field observations, camera trapping, and quadrate analysis, these species were observed to co-occur in rocky cavities in Ajodhya hills at several locations. Evidence for this included fresh pangolin tail drag marks, claw prints, footprints, scales, porcupine quills, teeth marks, and faecal matter in the same locations within the study area. Quadrate analysis showed that the trees housing the target prey species of the Indian Pangolin as well as the trees bearing fruits favoured by the Indian Crested Porcupine, occurred at maximum frequency within the Quadrate area. We hypothesise that pangolins and porcupines co-occupy rocky cavities for protection from poachers, who can easily break into more typical burrows and set traps in front of them. This may be an example of adaption to poaching, which demonstrates the necessity of conservation measures to alleviate severe anthropogenic pressure.

Ultimate bearing capacity analysis and structural optimization of packer slip

The packer's slips indent the inner wall of the casing, leaving a series of marks between the teeth of the slips and the inner wall of the casing. Excessive bite depth can result in damage to the inner wall of the casing, potentially leading to failure. To minimize damage to the inner wall of the casing and improve the ultimate bearing capacity of the slip, a three-dimensional finite element analysis model of the slips is developed and validated through laboratory experiments. The optimization objective is to minimize casing damage and maximize bearing capacity. This paper examines the correlation between the residual collapse strength of the casing and the maximum depth of slips penetrating the inner wall. It determines the critical depth value by calculating the extrusion force endured by the inner wall of the casing as an optimization evaluation index. At the same time, the optimal structural parameters of the slips were determined through numerical simulation and orthogonal experiments. These parameters include a 90° dental angle, a 21° inner cone angle, a 219 mm outer diameter, and a 6.5 mm tooth pitch. The research results indicate that the equivalent stress of the improved slip has decreased by 8.66 %. The equivalent stress on the inner wall of the casing has been reduced by 9.34 %, and the maximum tooth mark depth of the casing has decreased by 30.48 %. Furthermore, the ultimate bearing capacity of the slip has increased by 2.24 times. Research has shown that the improved slip not only reduces damage to the inner wall of the casing and minimizes stress concentration on the slip, but also increases the ultimate bearing capacity of the slip. The research results can serve as a reference for the study and application of packers.

Puma (Puma concolor) modifications on medium-sized mammals: Can its taphonomic signature be differentiated from other South American carnivores?

The aim of this article is to characterize the taphonomic signature of puma (Puma concolor) on non-ingested bone assemblages of medium-sized mammals. We conducted an experiment in a biopark where two captive pumas were fed ten European rabbits (Oryctolagus cuniculus). The analysis of the remains showed a highly fragmented assemblage of skeletal remains, mainly dominated by skull fragments and complete distal bones of the limbs. The remains displayed a variety of tooth marks, with punctures ranging in size from 3 mm to 8 mm. We compared these results with similar experiments conducted with Pampas fox (Lycalopex gymnocercus) and Geoffroy’s cat (Leopardus geoffroyi). Only minor differences were noted, such as the range of mark sizes and the specimens' medians. In conclusion, the three carnivores' taphonomic signatures are very similar regarding medium-sized prey and non-ingested samples. Future analysis, including the study of ingested remains and pit measurements, will deepen our understanding of the potential differences.

Insights on the oldest terror bird (Aves, Phorusrhacidae) from the Eocene of Argentina

ABSTRACT Phorusrhacidae, commonly known as terror birds, constitutes a group of Cariamiformes that lived mainly in South America during the Cenozoic. The oldest record is represented by an isolated distal end of tibiotarsus (MLP-PV 75-II-3-22) discovered in the Lutetian (middle Eocene) levels of the Sarmiento Formation exposed in the Cañadón Vaca locality (Chubut Province, Argentina). Despite being frequently cited as the oldest specimen of Phorusrhacidae, this specimen has never been figured or comprehensively described. Motivated by this gap and recognising the significance of this finding, we conducted a detailed comparison of the tibiotarsus MLP-PV 75-II-3-22 with those of other species, assigning it to an indeterminate species of Psilopterinae with an estimated body mass of approximately 5 kg. Furthermore, following the identification of numerous tooth marks on the distal surface, we hypothesised that this small phorusrhacid may have been subjected to an attack or scavenging event by a small-to-medium predator, such as Nemolestes spalacotherinus, a hypercarnivorous marsupial previously recorded in the Cañadón Vaca assemblage.

Bite and tooth marks on sauropod dinosaurs from the Morrison Formation.

Tooth-marked bones provide important evidence for feeding choices made by extinct carnivorous animals. In the case of the dinosaurs, most bite traces are attributed to the large and robust osteophagous tyrannosaurs, but those of other large carnivores remain underreported. Here we report on an extensive survey of the literature and some fossil collections cataloging a large number of sauropod bones (68) from the Upper Jurassic Morrison Formation of the USA that bear bite traces that can be attributed to theropods. We find that such bites on large sauropods, although less common than in tyrannosaur-dominated faunas, are known in large numbers from the Morrison Formation, and that none of the observed traces showed evidence of healing. The presence of tooth wear in non-tyrannosaur theropods further shows that they were biting into bone, but it remains difficult to assign individual bite traces to theropod taxa in the presence of multiple credible candidate biters. The widespread occurrence of bite traces without evidence of perimortem bites or healed bite traces, and of theropod tooth wear in Morrison Formation taxa suggests preferential feeding by theropods on juvenile sauropods, and likely scavenging of large-sized sauropod carcasses.

Prey body size generates bias for human and avian agents: Cautions for interpreting small game assemblages

Identifying the accumulating agent(s) of small animal assemblages at archaeological sites is challenging given the range of behaviors, skeletal plans, and body sizes of prey species as well as the range of potential predators. Although mammalian carnivores, raptors, and humans are considered typical predators of small game, there are many contexts—especially in island ecosystems—where humans and raptors are the primary agents for small animal assemblages in the absence of mammalian carnivores. Moreover, smaller animals tend to range in body sizes in these geographically restricted ecosystems. This study aims to broadly explore: 1) how small animal body size affects the taphonomic signature(s) of human and avian predation; and 2) how human and avian-generated small game assemblages compare with one another. To investigate these questions, this study compared the resulting taphonomic patterns of small animal predation by raptors and humans using data collected during a controlled-feeding experiment and an observational study, respectively. In the controlled-feeding experiment, deceased laboratory rats (Rattus norvegicus domestica) (50–500 g) were fed to two Milky Eagle Owls (Ketupa lacteus), one King Vulture (Sarcoramphus papa), and two Lappet-Faced Vultures (Torgos tracheliotos). In the observational study, we explored how humans processed various species of small prey ranging in body mass (80–5000 g) by analyzing anthropogenic modifications (i.e., cutmarks, tooth marks, burning). The resulting small animal assemblages were analyzed post-consumption for skeletal element representation, fragmentation and breakage patterns, and bone surface modifications. Results show that small prey body size significantly affects pre-depositional patterning in terms of skeletal element survival, butchering intensities, and cutmark frequencies. Furthermore, our experimentally generated assemblages show that breakage, fragmentation, and element relative abundance patterns can be used to distinguish between human and avian-accumulated assemblages in the archaeological record.

Puncture game: let's play with the canines of carnivores

- Predator teeth, especially canines, leave circular marks as pits and punctures on the bone surface of prey. The morphology and dimensions of puncture marks are related to different factors, both in terms of the predator itself (age, sex) and the nature of the impacted bone. The aim of this study is to examine the variability of puncture marks made by various predator species through the biometrical analysis of canines. Such an approach highlights the wide dimensional overlap and helps define the range of potential puncture production from smaller to larger carnivore species. The results draw attention to the use of simple measurements in the analysis of tooth marks on bone. Notwithstanding, more sophisticated multifactorial integrative approaches (predator and prey) are still needed.

363 The Use of Printed Radiographs to Document Dental Extractions for Alveolar Bone Graft Patients

Abstract Aim Recent cases of additional operations had to be offered prior to an alveolar bone graft (ABG) to complete dental extractions. Appropriate planning is important to avoid multiple GAs or the potential extraction of a wrong tooth. This quality improvement project was performed to assess and improve our practice. Method As a gold-standard, all dental extractions should be correctly identified and documented on printed orthopantograms (OPG) or upper standard occlusal (UOS) radiographs at the time of ABG planning. Documentation should include their timing (pre- vs intra-operative), a cross tooth marking on the radiograph, signed by two consultants, and filed with the consent form. In the first audit cycle we completed retrospective data collection of the above parameters for all ABG clinic patients between June and August 2021. After discussion with the stakeholders and implementation of changes, prospective data was collected for the second cycle, from October to December 2021. Results The documentation of the date of the OPG and UOS improved from 26.6% (4/15) to 100% (11/11). For 1 of the patients in the 2nd cycle, no OPG was done, as the patient's dental development didn't justify it. For the preoperative extraction cases, the presence of printed OPG in file increased from 53.8% (7/13) to 100%, marking of teeth improved from 57.1% (4/7) to 83.3% (5/6), and filing of the consent forms remained stable around 70%. Conclusions Adherence to the gold-standard was improved in most aspects as a result of this quality improvement project. Further changes will be introduced to achieve 100% compliance rate.

Genetic mapping of craniofacial traits in the Mexican tetra reveals loci associated with bite differences between cave and surface fish

BackgroundThe Mexican tetra, Astyanax mexicanus, includes interfertile surface-dwelling and cave-dwelling morphs, enabling powerful studies aimed at uncovering genes involved in the evolution of cave-associated traits. Compared to surface fish, cavefish harbor several extreme traits within their skull, such as a protruding lower jaw, a wider gape, and an increase in tooth number. These features are highly variable between individual cavefish and even across different cavefish populations.ResultsTo investigate these traits, we created a novel feeding behavior assay wherein bite impressions could be obtained. We determined that fish with an underbite leave larger bite impressions with an increase in the number of tooth marks. Capitalizing on the ability to produce hybrids from surface and cavefish crosses, we investigated genes underlying these segregating orofacial traits by performing Quantitative Trait Loci (QTL) analysis with F2 hybrids. We discovered significant QTL for bite (underbite vs. overbite) that mapped to a single region of the Astyanax genome. Within this genomic region, multiple genes exhibit coding region mutations, some with known roles in bone development. Further, we determined that there is evidence that this genomic region is under natural selection.ConclusionsThis work highlights cavefish as a valuable genetic model for orofacial patterning and will provide insight into the genetic regulators of jaw and tooth development.

A comparative taphonomic study of tooth marks caused by Iberian wolves (Canis lupus signatus) and domestic hunting dogs (Rehala) (Canis familiaris) on bovine scapulae, for taxonomic differentiation

For many years, the conflict between humans and wolves has persisted due to the death of livestock attributed to the attack of these animals and dogs, causing high economic costs to owners and governments. To remedy this problem, differential compensation programs have been established for the affected owners, depending on the attacker. Obtaining these benefits requires evidence to demonstrate the veracity of the complaint. Reliable approaches are needed nowadays to detect the predator, beyond any reasonable doubt. Although the analysis of teeth marks on bones has been used to differentiate carnivores, especially for archaeological purposes, its interpretation for forensic purposes is still ambiguous, due to the high range of factors that can influence tooth mark patterns, and it has scarcely been considered in previous work. This study analyzed and compared the tooth marks caused by captive Iberian wolves and by a group of domestic hunting dogs (rehala) on fresh, and disarticulated (isolated) bovine scapulae, for taxonomic differentiation purposes. Wolves showed a higher rate of modification throughout the study and, although tooth marks caused by wolves tend to be larger and wider than those caused by dogs, in most cases it was possible to find overlap between the two subspecies. Bone modifications are conditioned by a number of factors intrinsic to the scavenger or predator species, and intrinsic to the aggressor and the environment, that must be considered during the interpretation of tooth marks found on bones at a crime scene. Along with the comprehensive analysis of all evidence, the analysis of new variables of tooth marks on bones, using novel image processing methodologies and statistical analysis, has shown high potential to identify the morphological and/or morphometric variables that allow taxonomic differentiation

Sharing food with hyenas: a latrine of Pachycrocuta brevirostris in the Early Pleistocene assemblage of Fuente Nueva-3 (Orce, Baza Basin, SE Spain)

The Early Pleistocene archeological site of Fuente Nueva-3 (FN3) preserves some of the oldest evidence of hominin presence in Western Europe, including a huge assemblage of Oldowan tools and evidence of butchering and marrow processing of large mammal bones. Moreover, there is also evidence of the regular presence of carnivores at the site, including a small proportion of bones that show tooth marks, the majority of which can be attributed to the giant, short-faced hyena Pachycrocuta brevirostris, and there are 220 coprolites, most of them from the Upper Archeological Level. In order to identify the defecating agent, we analyze here the coprolites and compare them with other specimens from the literature and with scats from zoo spotted hyenas (Crocuta crocuta). The morphology, color, size, and chemical composition of the FN3 coprolites allow us to attribute them to the hyena P. brevirostris, which is also represented at the site by fossil specimens. In addition, we evaluate the origin of the accumulation of coprolites and discuss on the role played by the scavenging hyenas in the accumulation and modification of the bone remains unearthed at the site, which allows evaluating the contribution of the giant hyena to this Early Pleistocene site. Finally, based on the lithology of layer 5 of the Upper Archeological Level, fine sands and clays deposited in a salt-lake environment, we hypothesize that this layer may have acted as a quicksand where large-sized animals like elephants were trapped and their carcasses lured scavenging carnivores.