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Craniofacial phenomics has opened up numerous opportunities to correlate genetic and epigenetic factors to craniofacial phenotypes in order to improve our understanding of growth and development in health and disease. Three-dimensional (3D) imaging has played a key role in advancing craniofacial phenomics by facilitating highly sensitive and specific characterizations of craniofacial and dental morphology. Here we describe the use of micro-computed tomography (micro-CT) to image the murine craniofacial complex, followed by surface reconstruction for traditional morphometric analyses. We also describe the application of geometric morphometrics, based on Generalized Procrustes Analysis, for use in human premolars. These principles are interchangeable between various vertebrate species, and between various surface imaging techniques (including micro-CT and 3D surface scanners), offering a high level of versatility and precision for extensive phenotyping of the entire craniofacial complex., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Between 1990 and 2018, the Defense POW/MIA Accounting Agency submitted 2177 cranial elements and 1565 teeth to the Armed Forces Medical Examiner System-Armed Forces DNA Identification Laboratory for DNA testing. In an effort to identify missing United States service members, materials were recovered from wartime losses inclusive of World War II, the Korean War, and Southeast Asia. Using four different DNA extraction protocols, DNA testing was performed using mitochondrial DNA Sanger sequencing, modified AmpFlSTR ® Yfiler™, AmpFlSTR ® MiniFiler™, PowerPlex ® Fusion, or Next Generation Sequencing. This paper aims to provide optimal strategies for the DNA testing of skeletonized cranial materials. Cranial elements produced the most consistent results in Sanger sequencing using an organic purification; however, teeth were most successful for the same platform with an inorganic purification. The inverse is true for STR testing of cranial bones. Of the cranial elements, the temporal provided the most consistent results., (© 2019 American Academy of Forensic Sciences.)

Middle to Late Pleistocene human evolution in East Asia has remained controversial regarding the extent of morphological continuity through archaic humans and to modern humans. Newly found ∼300,000-y-old human remains from Hualongdong (HLD), China, including a largely complete skull (HLD 6), share East Asian Middle Pleistocene (MPl) human traits of a low vault with a frontal keel (but no parietal sagittal keel or angular torus), a low and wide nasal aperture, a pronounced supraorbital torus (especially medially), a nonlevel nasal floor, and small or absent third molars. It lacks a malar incisure but has a large superior medial pterygoid tubercle. HLD 6 also exhibits a relatively flat superior face, a more vertical mandibular symphysis, a pronounced mental trigone, and simple occlusal morphology, foreshadowing modern human morphology. The HLD human fossils thus variably resemble other later MPl East Asian remains, but add to the overall variation in the sample. Their configurations, with those of other Middle and early Late Pleistocene East Asian remains, support archaic human regional continuity and provide a background to the subsequent archaic-to-modern human transition in the region., Competing Interests: The authors declare no conflict of interest.

Dalatiid sharks are members of a family of predominantly small, midwater meso- and bathypelagic chondrichthyans. The family is notable for both its number of monotypic genera and high morphological disparity. Three of the seven dalatiid genera are known only from holotype specimens (Mollisquama parini) or from only a handful of specimens (Euprotomicroides zantedeschia, Heteroscymnoides marleyi), with the only detailed anatomical work consistent across all taxa being studies of dentition. Here, we present detailed anatomical description of the second-ever specimen of Mollisquama (Mollisquama sp.) covering chondrocranial, jaw, dental, and muscular anatomy, derived from a phase-contrast synchrotron microtomographic scan. Mollisquama sp. is unique among dalatiids in possessing a deep carinal process, extending ventrally from the bar between the subethmoid region and basal angle in squaloid sharks, containing a large fenestra infiltrated by the suborbitalis muscle. Mollisquama sp. also exhibits additional possibly diagnostic features, including a planar configuration of the labial cartilages and the absence of labial folds; a pad-like orbital process on the palatoquadrate; and the origination of the suborbitalis muscle solely on the carina, rather than the intraorbital wall. Character optimization of anatomical data onto a phylogeny of dalatiid sharks suggests Mollisquama sp. to be among the most specialized in the family, expanding the existing dalatiid morphospace. However, the functional significance of such transformations remains unclear. Synchrotron-derived data, which do not require chemical pretreatment of specimens, may elucidate soft-tissue functional correlates in future studies of undersampled taxa, such as dalatiids., (© 2018 Anatomical Society.)

The Rhomaleosauridae were a clade of Jurassic plesiosaurians, characterized by triangular skulls, an elongated preorbital region, marked premaxillary-maxillary constriction, and intermediate body proportions that fall between pliosauromorphs and plesiosauromorphs. Despite recent progress in the study of dental replacement in plesiosaurians, the replacement features in rhomaleosaurids have not been studied yet. Here, the dental features of the rhomaleosaurid Maresaurus coccai Gasparini, 1997 are described and analyzed based on the holotype specimen. Regarding symmetry, it was determined that M. coccai shows symmetrical replacement in the maxillary-premaxillary and asymmetrical replacement in the dentary. Additionally, the tooth replacement cycle period (TRCP) of two alveoli was determined for the dental series, except for the anterior part of the left mandibular ramus, which presents an TRCP of three, an asymmetry considered here as teratology. This result indicates that the replacement cycle period (TRCP) of the two alveoli would correspond to a primitive character for Plesiosauria, displaying an increase of TRCP from two to three alveoli in taxa comparatively more derived within Pliosauridae. [ABSTRACT FROM AUTHOR]

Since discovery and description of the species, Sahelanthropus tchadensis has been at the centre of a great discussion around its classification as a hominin - the first of our lineage - or an ape. Many studies have been conducted in order to clarify this question, especially studies based on the morphology of the cranium and the post-cranial remains. In this study, we analysed the posterior dentition of S. tchadensis in relation to those of other hominins and chimpanzees, using a multivariate comparative metric analysis. Our results suggest that the posterior dentition of the Chad material lies in the range of well-established early Plio-Pleistocene hominins, supporting its classification as part of the hominin lineage. [ABSTRACT FROM AUTHOR]

Several recumbirostran 'microsaurs' are known from early Permian sites across Germany, including the Tambach Formation in Thuringia, central Germany. The only 'microsaur' thus far described from the Tambach Formation was the ostodolepid recumbirostran Tambaroter carrolli. However, there is also the documented presence of an undescribed recumbirostran 'microsaur' at the well-known Bromacker locality. The Bromacker locality is highly recognized and best known for its very diverse and extremely well-preserved terrestrial tetrapod assemblage combined with the co-occurrence of an exceptional vertebrate ichnofossil record. Here we describe a second new recumbirostran taxon from the Tambach Formation, which is also the first from the Bromacker locality itself. Phylogenetic analysis indicates that the new taxon, Bromerpeton subcolossus gen. et sp. nov., is a brachystelechid recumbirostran, a group also known elsewhere in Germany. The following features differentiate Bromerpeton from the other members of the clade: the presence of 13 maxillary teeth, narrow postorbitals that do not substantially contribute to the postorbital region of the skull, the frontal does not contribute to the orbital margin, and the presence of five manual digits. This new recumbirostran 'microsaur' further adds to the unique ecosystem that is preserved at the Bromacker locality, granting us a better understanding of what was living underfoot the larger more well-known animals at the locality. Likewise, it expands our understanding of the evolution of recumbirostran 'microsaurs', especially with regards to digit and limb reduction within the clade. [ABSTRACT FROM AUTHOR]

The Lufeng locality of China was a major biodiversity hotspot for sauropods and tritylodontids during the Early Jurassic. We describe a partly crushed cranium with complete dentition and dentaries from the Early Jurassic Lufeng Formation of China that we refer to Lufengia. The upper postcanine row length is 10.27 mm, representing one of the smallest tritylodontids to date. Lufengia and Dianzhongia are comparable in the upper postcanine dental pattern in having upper postcanine teeth with the cusp formula 2-3-3 and a small distolingual cusp. Based on the new discovery, Dianzhongia is here considered to be an older individual of Lufengia. Through the micro-computed tomography (micro-CT) of the fossil, differing paths of upper and lower dental replacements alongside new details about tooth replacement in tritylodontids have been revealed. [ABSTRACT FROM AUTHOR]

The consistency of the diet may affect the development and maintenance of the muscular and bony parts of the masticatory apparatus. Therefore, we investigated the effect of chronic intake of liquid nutrition (Fresubin) on the growth and maintenance of the weight and size of the skull, mandible, and teeth in Wistar rats fed with liquid nutrition during different developmental periods: (i) from weaning to adulthood, (ii) only in the juvenile period, or (iii) only in adulthood. We found that in all groups of rats fed with liquid nutrition, the skull and the mandible were significantly lighter in weight than those of control rats fed exclusively with pelleted chow from weaning to adulthood. In addition, in rats fed with liquid nutrition, the length of the mandible was significantly increased, whereas the height of the mandible and the length of the upper incisors were reduced. Our data indicate that food consistency may profoundly affect the growth pattern and the maintenance of the mass and size of skull bones and teeth during different periods of life. The extent of the effect was found to depend on the period during which liquid nutrition is provided and on the duration of its intake. In conclusion, the findings indicate that prolonged intake of liquid nutrition can significantly affect the development of the bone part of the masticatory apparatus. [ABSTRACT FROM AUTHOR]

Orthodontic treatment is a common dental treatment. A complete treatment often takes several years and is costly. In order to increase the degree of satisfaction and reduce the gap between the expectations of the patient and the limitations of orthodontics, orthodontists and patients should have sufficient communication. A simulation system can provide a good channel for communication between orthodontists and patients. This paper proposes a 3D dentist–patient communication system for the simulation of orthodontics in advance. The system collects the clinical paradigms of orthodontic cases, which must contain photos from before, during, and after maxillofacial treatment. This research simulates treatment processes by tuning a 3D virtual model of the oral and maxillofacial areas, including the face, mouth, and teeth, to demonstrate the processes of clinical paradigms. These 3D models could be edited and synthesized to generate new 3D models for simulation with the 3DS Max tool. In addition, the proposed system provides a function for the orthodontist to manually operate the 3D virtual model, such as tooth arrangement, morphing of the gums with movement of the teeth, the placement (attachment) of arch-wires and brackets, and changes of facial appearance. The orthodontist can demonstrate the treatment processes, show movements of the teeth, and answer possible questions from the patient about the treatment processes by using the 3D model. To show the effectiveness of the proposed system, a questionnaire about the system was also used to demonstrate its acceptance, usability, and validity. Qualitative interviews with dentists and questionnaires for patients about the system are both performed. The results showed that the proposed system is an effective vehicle for communication between patients and orthodontists. [ABSTRACT FROM AUTHOR]

There are different descriptions of allometric relationships between important components of the mammalian skull. Craniofacial evolutionary allometry describes a pattern of increasing facial cranium in larger skulls. Another body of literature describes disproportionately larger teeth in smaller species or specimens, matching anecdotal observations with dental problems in dwarf breeds whose teeth appear "too large for their skulls." We test the scaling of tooth row length with body size and skull length in a data set comprising 114 domestic horses (representing 40 breeds) and in another data set of 316 domestic cattle (of >60 breeds). We demonstrate that smaller skulls have a relatively longer tooth row in both horses and cattle; larger specimens have relatively shorter tooth rows. Whereas in horses, larger skulls have a relatively longer diastema, the distance of the mesial maxillary premolar to the premaxilla was proportional to cranium length in cattle. While the reasons for these patterns remain to be detected, they support the hypothesis that tooth size might be less "evolvable," in terms of time required for changes, than body size. The pattern may affect (i) the selective breeding for dwarf breeds by setting minimum constraints for skull size, as described previously for domestic horses with the same data set; (ii) the susceptibility of small breeds for dental problems; and (iii) differences in chewing efficiency between breeds of different sizes. The findings support the existing concept that scaling of tooth to body size across taxa becomes more isometric the longer these taxa are separated in evolutionary time. Research Highlights: In domestic horses and cattle, smaller breeds have relatively longer tooth rows.(i veterinary observations of "crammed teeth" in small breeds.(iii relatively lower chewing intensity of smaller specimens. [ABSTRACT FROM AUTHOR]

This study aims to determine the differences in skull between Asian and golden palm civets by geometric morphometric method. The landmarks were marked on these photographs, and principal component, classical cluster and canonical variance analyses were performed. The method of geometric morphometry of the skull is a powerful tool used to differentiate the species. Fourteen and 20 homologous landmarks were marked using tpsutil and tpsdig2 programs on the frontal and palatinal directional photographs, respectively. As a result of the study, the first principal component (PC1) accounted for 33.586% on the frontal view, 41.602% on the palatinal view of the total shape differences, respectively. Distinctive differences on the frontal and palatinal view were observed in the caudal, rostrolateral and the last molars and the caudal palatine, respectively. [ABSTRACT FROM AUTHOR]

The temnospondyl clade Amphibamiformes includes small newt-like forms that dwelled in freshwater lakes in the Pennsylvanian and Lower Permian of Europe and North America. Here we report a new genus and species, Piasimotriton kochovi, from the early Permian Boskovice Basin, Czech Republic. It has a unique combination of characters, among which the following ones rank as most important: (1) extremely elongated basipterygoid process forming a paired elongate facet for articulation with basal plate, (2) parasphenoid with broad and much abbreviated basal plate, about 2.5 times wider than long, (3) tooth crown with lateral crest, (4) premaxilla with 18 tiny teeth, and (5) a strong dermal ornament on the median skull elements. Piasimotriton kochovi has probably pedicellate teeth. Phylogenetic analysis finds Piasimotriton nests with the Melanerpeton clade with Melanerpeton, Leptorophus, and Schoenfelderpeton, with "Melanerpeton" gracile forming its sister taxon. The possession of various features that are also found in lissamphibians indicates a more widespread distribution of these within their putative stem-group. The stomach content of Piasimotriton kochovi consists of segmented thorax remains of small crustaceans. Piasimotriton probably competed with osteichthyans for arthropod prey and was only present in a short time interval of the lake's existence. [ABSTRACT FROM AUTHOR]

The fossil record of dipnoans is mostly represented by tooth plates and jaw bones, whereas nearly complete or complete skulls are rare. Here, we describe a new dipnoan from the Santonian (Upper Cretaceous) of Patagonia (Argentina) using three-dimensional renderings generated by CT scans. It consists of a near-complete skull and postcranial material. Rinconodus salvadori n. gen., n. sp. is diagnosed by a combination of features, such as medial series composed of two unpaired bones, mediolateral series composed of two paired bones, lateral series with at least one bone, medial edge of tooth plates longer than the lingual edge and equally curved, upper tooth plates contiguous or close to one another with five denticulations, lower tooth plates widely separated with four denticulations, first denticulation of upper tooth plates longer and thinner than the remaining denticulations, and posteriorly curved, first denticulation of lower tooth plates relatively straight and longer than the remaining ones, among other characters. The new species is based on the first two nearly complete Santonian dipnoan skulls from South America. Moreover, the materials presented here are the geologically youngest dipnoan remains consisting of a near-complete skull and postcranium from the Cretaceous of Gondwana. [ABSTRACT FROM AUTHOR]

We describe six specimens consisting of cranial remains and associated partial presacral axial series belonging to ornithuromorph birds from the Changma locality of the Lower Cretacous Xiagou Formation of northwestern Gansu Province, China. Comparison among specimens is limited by the paucity of overlapping elements, their differing exposed views, and, in some specimens, poor preservation. Despite this, three separate taxa are represented, evidenced by differences in their dentary dentitions: one specimen is edentulous, another has sharp, closely spaced, relatively high‐crowned and peg‐like teeth, and a third preserves blunt, relatively low‐crowned teeth placed in a communal groove, a morphology previously reported among adult birds only in Hesperornithiformes. We propose that the high‐crowned specimen may be referred to Gansus yumenensis based on shared similarities with the closely related Iteravis huchzermeyeri, including a very similar dentition and an edentulous premaxilla with elongate, unfused frontal processes and no palatal processes. The two other specimens are considered new taxa, for which we erect the names Meemannavis ductrix gen. et sp. nov. and Brevidentavis zhangi gen. et sp. nov. These new specimens confirm that the Changma locality is dominated by ornithuromorph birds and contribute to a better understanding of this important avifauna. The observed variation in dental morphology hints at trophic diversity like that observed in ornithuromorphs from the penecontemporaneous Jehol Group of northeastern China. [ABSTRACT FROM AUTHOR]

The present study provides a comprehensive osteological description of Pachypterus khavalchor from the family Horabagridae. Nine individuals of P. khavalchor representing both males and females collected from the type locality were cleared and double-stained to provide a description of osteological characteristics. The presence of an almost straight dorsal roof to the cranium, a long and protruding premaxilla with numerous rows of tiny, villiform teeth, a spoon-like lower jaw with villiform teeth projecting outward, and five long and ossified ceratobranchials, with the 5th ceratobranchial containing a set of 80 to 90 conical teeth, sheds light on the ecomorphological adaptation in P. khavalchor that may have led to the evolution of lepidophagy. Furthermore, a slight difference in the structure of the complex hypurapophysis was observed between males and females. The information on the osteology of the Khavalchor catfish forms a baseline for taxonomic research of the entire Horabagridae family comprising four genera with ten species distributed in Asia. [ABSTRACT FROM AUTHOR]

This study aimed to establish three-dimensional digital model new system from dental cast models and head films and verify the accuracy of the system to assess three-dimensional bone and tooth movement using a reconstructed bone-tooth integrated model, in cases treated by maxillary protractive new appliance. 12 patients (8 female and 4 male children), aged 6 years and 10 months on average (4 years and 10 months to 9 years and 11 months), with anterior cross bite due to skeletal factors participated in this study. They were treated by maxillary protractive new appliance. At an initial and the end of treatment recording, the upper teeth were reconstructed with digital models of the upper casts from the 3D Scanner STL data, the virtual skull were reconstructed with head films. The teeth area of the virtual skull models were replaced with the corresponding teeth of the digital models. Consequently the bone-teeth integrated models were reconstructed. As a result, bone and tooth movement was analyzed three-dimensionally. For the translation of the point A, anterior movement of the maxillary complex was 4.5mm on average on the global coordinate system. The rotation of the occlusal plane was 5.0°on average on the global coordinate system. Through reconstructing a bone-teeth integrated model, a three-dimensional digital model new system for analyzing bone and teeth movement was established. It was demonstrated that the maxillary protractive new appliance acts on the bone and effects in improving skeletal disharmony. The efficacy of the clinical application was suggested. [ABSTRACT FROM AUTHOR]

The Mompaderno cranium was found in 1883 at Baderna/Mompaderno in Croatian Istria. It was suspected to date from the Mesolithic or Neolithic period, but radiocarbon analyses, performed by accelerator mass spectrometry (AMS) on collagen extracted from two teeth, have provided an age range of 2,202–1928 cal. BC, which corresponds to the Early Bronze Age in the investigated region. Macroscopic observations and X‐ray micro‐tomography (micro‐CT) of the cranium have shown antemortem sharp force trauma on the frontal bones, probably caused by a bronze axe, and a related osteomyelitis likely caused by an infection of the wound. The study has also revealed a previous depressed fracture and an osteolytic area interpreted as intradiploic meningioma. Results provide rare and earliest evidence of interpersonal violence in the northern Adriatic region. [ABSTRACT FROM AUTHOR]

We report a new specimen of the plesiosaur Cardiocorax mukulu that includes the most complete plesiosaur skull from sub-Saharan Africa. The well-preserved three-dimensional nature of the skull offers rare insight into the cranial anatomy of elasmosaurid plesiosaurians. The new specimen of Cardiocorax mukulu was recovered from Bentiaba, Namibe Province in Angola, approximately three meters above the holotype. The new specimen also includes an atlas-axis complex, seventeen postaxial cervical vertebrae, partial ribs, a femur, and limb elements. It is identified as Cardiocorax mukulu based on an apomorphy shared with the holotype where the cervical neural spine is approximately as long anteroposteriorly as the centrum and exhibits a sinusoidal anterior margin. The new specimen is nearly identical to the holotype and previously referred material in all other aspects. Cardiocorax mukulu is returned in an early-branching or intermediate position in Elasmosauridae in four out of the six of our phylogenetic analyses. Cardiocorax mukulu lacks the elongated cervical vertebrae that is characteristic of the extremely long-necked elasmosaurines, and the broad skull with and a high number of maxillary teeth (28–40) which is characteristic of Aristonectinae. Currently, the most parsimonious explanation concerning elasmosaurid evolutionary relationships, is that Cardiocorax mukulu represents an older lineage of elasmosaurids in the Maastrichtian. [ABSTRACT FROM AUTHOR]

Five specimens of the late Permian cynodont Cynosaurus suppostus, inferred to represent an ontogenetic growth series, were imaged using X-ray microtomography in order to determine the pattern of tooth replacement for the species. Due to the small sample size, and damage to the rostrum in several specimens, replacement patterns of the incisors could not be accurately determined. Evidence supporting the presence of two maxillary canine loci in a juvenile Cynosaurus is presented. Replacement of the mandibular canines ceased at a basal skull length of ∼88 mm, whereas replacement of the maxillary canines ceased at a basal skull length of ∼90 mm. The final canine generation to erupt in both the maxillae and mandible had open-rooted apices. An alternating pattern of replacement is described for the maxillary and mandibular postcanine series. Postcanine replacement generations in the maxilla are seemingly separated by two tooth loci, whereas in the mandible replacement activity occurs at alternating loci. Cessation of replacement in the first maxillary postcanine locus (PC1) is synchronized with the eruption of the replacement tooth in the third locus (PC3). This cessation of replacement at PC1 results in a distal migration of the entire maxillary postcanine series. This pattern provides possible evidence for a finite number of replacement generations occurring at the active PC1. There appear to have been two replacement cycles per postcanine locus in Cynosaurus, which is a lower number of total replacements per postcanine locus than previously estimated for the Early Triassic basal cynodont Thrinaxodon liorhinus. [ABSTRACT FROM AUTHOR]

Sixteen specimens of the Early Triassic cynodont Galesaurus planiceps (including eight that were scanned using micro-computed tomography) representing different ontogenetic stages were assembled to study the dental replacement in the species. The growth series shows that the incisors and postcanines continue to develop and replace, even in the largest (presumably oldest) specimen. In contrast, replacement of the canines ceased with the attainment of skeletal maturity, at a basal skull length of ~90 mm, suggesting that Galesaurus had a finite number of canine replacement cycles. Additionally, the functional canine root morphology of these larger specimens showed a tendency to be open-rooted, a condition not previously reported in Mesozoic theriodonts. An alternating pattern of tooth replacement was documented in the maxillary and mandibular postcanine series. Both postcanine series increased in tooth number as the skull lengthened, with the mandibular postcanine series containing more teeth than the maxillary series. In the maxilla, the first postcanine is consistently the smallest tooth, showing a proportional reduction in size as skull length increased. The longer retention of a tooth in this first locus is a key difference between Galesaurus and Thrinaxodon, in which the mesial-most postcanines are lost after replacement. This difference has contributed to the lengthening of the postcanine series in Galesaurus, as teeth continued to be added to the distal end of the tooth row through ontogeny. Overall, there are considerable differences between Galesaurus and Thrinaxodon relating to the replacement and development of their teeth. [ABSTRACT FROM AUTHOR]

A large part of extant and past mammalian morphological diversity is related to variation in size through allometric effects. Previous studies suggested that craniofacial allometry is the dominant pattern underlying mammalian skull shape variation, but cranial allometries were rarely characterized within cranial units such as individual bones. Here, we used 3D geometric morphometric methods to study allometric patterns of the whole skull (global) and of cranial units (local) in a postnatal developmental series of nine-banded armadillos (Dasypus novemcinctus ssp.). Analyses were conducted at the ontogenetic and static levels, and for successive developmental stages. Our results support craniofacial allometry as the global pattern along with more local allometric trends, such as the relative posterior elongation of the infraorbital canal, the tooth row reduction on the maxillary, and the marked development of nuchal crests on the supraoccipital with increasing skull size. Our study also reports allometric proportions of shape variation varying substantially among cranial units and across ontogenetic stages. The multi-scale approach advocated here allowed unveiling previously unnoticed allometric variations, indicating an untapped complexity of cranial allometric patterns to further explain mammalian morphological evolution. [ABSTRACT FROM AUTHOR]

Cephalomys is the best-known cephalomyid, recorded in five localities in Argentina and known from well-preserved mandibles, fragments of skull, and a large number of isolated teeth, from both juveniles and adults. Despite this, a modern description is lacking and the validity of some species of Cephalomys has been questioned in the last few years. New material from the Deseadan locality of Cabeza Blanca (Chubut, Argentina), including skull fragments unknown for the species thus far, and well-preserved juvenile teeth, along with a large number of specimens from collections in Argentina, allow us to propose a more complete description of the genus and a new taxonomic arrangement for the Cephalomys species. We also analysed some dubious records of Cephalomys from Quebrada Honda and Pico Truncado and confirm that they are not part of this genus. We consider C. plexus to be a synonym of C. arcidens, we consider the combination previously proposed for C. bolivianus (as a species of Asteromys) to be valid, and we consider C. ceciae also to be a valid species. We performed a phylogenetic analysis including for the first time all cephalomyids (Cephalomys, Litodontomys, Cephalomyopsis, Soriamys and Banderomys) and possibly related genera (Perimys, Scotamys, Asteromys) to test the position of the family Cephalomyidae among the other caviomorph rodents, as well as its validity and internal relationships. The results recovered Cephalomyidae as a clade, including Cephalomys, Cephalomyopsis and Litodontomys. The monophyly of Cephalomys could not be confirmed. Soriamys and Banderomys were recovered within Cavioidea. Perimys, Scotamys and Asteromys were recovered within Chinchilloidea, and we analysed the implications of their positions within the group. The implications in terms of the biochron, distribution and evolutionary history of the Cephalomyidae, considering the new definition for the family proposed herein (including only Cephalomys, Cephalomyopsis and Litodontomys), are discussed, as well as inferences regarding caviomorph evolution at the scale of the entire group. [ABSTRACT FROM AUTHOR]

Skulls, jaws and teeth of wild terrestrial small mammals (Sciuridae, Soricidae, Erinaceidae, Talpidae, Gliridae, Arvicolidae, Muridae) are occasionally affected by anomalies and pathologies. The present study documents a total of 362 anomalies and 122 pathological changes across 20 different species. These are all based on data published in Germany, supplemented by our own records. Cases were classified into 14 different categories, according to bone and dental anomalies, fractures and inclusions, bone proliferation, dental disease and extreme wear of teeth. An additional category to specifically account for bone proliferation of the skull was not needed, but such findings are to be expected. The most frequent finding was abnormal tooth growth, particularly the elongation of the upper incisors. In individual cases, there was evidence that small mammals are able to recover even from serious injuries to the skull. [ABSTRACT FROM AUTHOR]

Here we present a description of the dipnoan remains collected from the middle to upper Norian (Upper Triassic) of Jameson Land, East Greenland. The specimens consist of isolated tooth plates and skull bones of Ptychoceratodus, the most complete Late Triassic dipnoan material from Greenland. This genus is reported for the first time from the Upper Triassic of Greenland. The studied material belongs to Ptychoceratodus rectangulus previously known from the middle–upper Norian of Germany. It fills the biogeographical gap between the records of the Germanic and the Jameson Land basins. A reconstruction of the skull roof is provided, based on isolated bones collected from the same bone-bed. Their good preservation enables recognition of the sensory line pits, arranged similarly as in the extant Protopterus, suggesting a comparable mode of life. This finding has implications for our understanding of the disparity in Ptychoceratodus dipnoans, as well as the morphology between closely related dipnoans of the Late Triassic ecosystems. [ABSTRACT FROM AUTHOR]

Objective: This study was conducted to compare vertical and horizontal periodontal measurements of posterior teeth on standardized panoramic and intraoral radiographs. Methods and materials: Standardized panoramic and periapical radiographs were made of 16 human skulls using ball bearings placed on the maxillary first molars to allow adjustment for horizontal and vertical magnification. Results: At 14 of 19 measurement sites there was no significant difference between measurements on the 2 radiographic film types. At 4 sites vertical measurements on panoramic radiographs were significantly larger than on periapical radiographs (0.80 to 1.37 mm). At one site horizontal measurements were significantly greater on periapical radiographs (0.88 mm). Conclusions: If there is adjustment of the raw data for magnification as suggested in this study, panoramic radiographs may be used for measurement studies in the posterior region once the patients are positioned appropriately within the focal trough of the machines and the magnification range for the posterior focal trough is used for adjustment of data. [ABSTRACT FROM AUTHOR]

Non‐avian reptiles are good models to investigate structural and developmental differences between amniotes. Investigations of craniofacial development in a complete series of embryos from oviposition up to hatching are still relatively rare. Consideration of a complete series can reveal developmental events that were previously missed, and thus correct or confirm theories about developmental events. The Egyptian Sand snake, Psammophis sibilans, has been a key species in descriptions of the snake skull development. However, published work was based on a limited sample of specimens collected from the wild. Here, we supplement previous descriptions with an illustrated account of skull development in P. sibilans based on a staged series of embryos and histological sections. Our findings largely agree with those of previous authors, although we record differences in developmental timing, confirming the presence of an egg tooth in this species. We add further observations on the enigmatic fenestra X, showing that it closes rather than merging with the prootic notch. Our observations revealed the likely contribution of the tectum posterius to the occipital roof, the presence of an internal carotid foramen (possibly transitory or variable), and the formation of the initial laterosphenoid pillar. [ABSTRACT FROM AUTHOR]

Until recently the immediate aftermath of the Hangenberg event of the Famennian Stage (Upper Devonian) was considered to have decimated sarcopterygian groups, including lungfish, with only two taxa, Occludus romeri and Sagenodus spp., being unequivocally recorded from rocks of Tournaisian age (Mississippian, Early Carboniferous). Recent discoveries of numerous morphologically diverse lungfish tooth plates from southern Scotland and northern England indicate that at least 10 dipnoan taxa existed during the earliest Carboniferous. Of these taxa, only two, Xylognathus and Ballgadus, preserve cranial and postcranial skeletal elements, which have yet to be described. Here we present a description of the skull of a new genus and species of lungfish, Limanichthys fraseri gen. et sp. nov., which hails from the very earliest Tournaisian in the Ballagan Formation of Burnmouth, southern Scotland. The new specimen represents the earliest definitive Tournaisian lungfish skull material, thus providing an invaluable insight into the response of this group – and, indeed, Sarcopterygii as a whole – immediately following the latest Devonian Hangenberg event. Phylogenetic analysis places Limanichthys fraseri within the Devonian 'phaneropleurid-fleurantiid' grade of lungfish and shows that the Carboniferous lungfish represent forms that have their origins deep in the Middle and Late Devonian as well as those from a unique Carboniferous radiation. [ABSTRACT FROM AUTHOR]

The Sthenurinae were a diverse subfamily of short-faced kangaroos that arose in the Miocene and diversified during the Pliocene and Pleistocene. Many species possessed skull morphologies that were relatively structurally reinforced with bone, suggesting that they were adapted to incorporate particularly resistant foods into their diets. However, the functional roles of many unique, robust features of the sthenurine cranium are not yet clearly defined. Here, the finite element method is applied to conduct a comprehensive analysis of unilateral biting along the cheek tooth battery of a well-represented sthenurine, Simosthenurus occidentalis. The results are compared with those of an extant species considered to be of most similar ecology and cranial proportions to this species, the koala (Phascolarctos cinereus). The simulations reveal that the cranium of S. occidentalis could produce and withstand comparatively high forces during unilateral biting. Its greatly expanded zygomatic arches potentially housed enlarged zygomaticomandibularis muscles, shown here to reduce the risk of dislocation of the temporomandibular joint during biting with the rear of a broad, extensive cheek tooth row. This may also be a function of the zygomaticomandibularis in the giant panda (Ailuropoda melanoleuca), another species known to exhibit an enlarged zygomatic arch and hypertrophy of this muscle. Furthermore, the expanded frontal plates of the S. occidentalis cranium form broad arches of bone with the braincase and deepened maxillae that each extend from the anterior tooth rows to their opposing jaw joints. These arches are demonstrated here to be a key feature in resisting high torsional forces during unilateral premolar biting on large, resistant food items. This supports the notion that S. occidentalis fed thick, lignified vegetation directly to the cheek teeth in a similar manner to that described for the giant panda when crushing mature bamboo culms. [ABSTRACT FROM AUTHOR]

Saturnalia tupiniquim is a sauropodomorph dinosaur from the Late Triassic (Carnian–c. 233 Ma) Santa Maria Formation of Brazil. Due to its phylogenetic position and age, it is important for studies focusing on the early evolution of both dinosaurs and sauropodomorphs. The osteology of Saturnalia has been described in a series of papers, but its cranial anatomy remains mostly unknown. Here, we describe the skull bones of one of its paratypes (only in the type-series to possess such remains) based on CT Scan data. The newly described elements allowed estimating the cranial length of Saturnalia and provide additional support for the presence of a reduced skull (i.e. two thirds of the femoral length) in this taxon, as typical of later sauropodomorphs. Skull reduction in Saturnalia could be related to an increased efficiency for predatory feeding behaviour, allowing fast movements of the head in order to secure small and elusive prey, a hypothesis also supported by data from its tooth and brain morphology. A principal co-ordinates analysis of the sauropodomorph jaw feeding apparatus shows marked shifts in morphospace occupation in different stages of the first 30 million years of their evolutionary history. One of these shifts is observed between non-plateosaurian and plateosaurian sauropodomorphs, suggesting that, despite also having an omnivorous diet, the feeding behaviour of some early Carnian sauropodomorphs, such as Saturnalia, was markedly different from that of later Triassic taxa. A second shift, between Late Triassic and Early Jurassic taxa, is congruent with a floral turnover hypothesis across the Triassic-Jurassic boundary. [ABSTRACT FROM AUTHOR]

This study reevaluates the tooth morphology used to define species within the genus Edestus (Chondrichthyes, Euchondrocephali). Known as the scissor tooth shark, Edestus produced a unique dentition of spiraled tooth families positioned in the symphysis (midline) of the upper and lower jaws. Morphometric analysis of more than 200 ejected teeth and intact spiral tooth whorls demonstrates that teeth from the upper and lower whorls differ in shape and ontogeny. Comparison of these data to the type specimens of 13 existing species reduces the number of morphologically distinct Edestus to just four species and refines the stratigraphic occurrence and expansion of the group. E. triserratus has a narrow bullet-shaped crown that points anteriorly and has roots of intermediate length. E. minor crowns have a wider triangular base, whereas the crowns of E. heinrichi form nearly equilateral triangles and are supported by an elongated root. E. vorax, which also has roughly equilateral triangular crowns, has short and deep roots, and is only known from very large specimens that are distinct from the growth series of E. heinrichi. Tooth and whorl morphologies among the species are consistent with cranial anatomy observed in a juvenile E. heinrichi and with transverse tooth-wear patterns to suggest Edestus used a forward to backward slicing motion to bite its prey. Extrapolating body size from tooth whorl length provides a conservative estimate that E. heinrichi could exceed 6.7 m in length. Edestus fossils are recovered from coastal marine to estuarine deposits spanning roughly six million years (313–307 Ma). Edestus first appears in England during the latest Bashkirian (313 Ma, Carboniferous), a few million years after its most closely resembling genus Lestrodus. Diversification and range expansion of Edestus coincides with the Moscovian transgression that flooded Laurentia and the Russian platform. [ABSTRACT FROM AUTHOR]

The genus Mystriosaurus, established by Kaup in 1834, was one of the first thalattosuchian genera to be named. The holotype, an incomplete skull from the lower Toarcian Posidonienschiefer Formation of Altdorf (Bavaria, southern Germany), is poorly known with a convoluted taxonomic history. For the past 60 years, Mystriosaurus has been considered a subjective junior synonym of Steneosaurus. However, our reassessment of the Mystriosaurus laurillardi holotype demonstrates that it is a distinct and valid taxon. Moreover, we find the holotype of "Steneosaurus" brevior, an almost complete skull from the lower Toarcian Whitby Mudstone Formation of Whitby (Yorkshire, UK), to be a subjective junior synonym of M. laurillardi. Mystriosaurus is diagnosed in having: a heavily and extensively ornamented skull; large and numerous neurovascular foramina on the premaxillae, maxillae and dentaries; anteriorly oriented external nares; and four teeth per premaxilla. Our phylogenetic analyses reveal M. laurillardi to be distantly related to Steneosaurus bollensis, supporting our contention that they are different taxa. Interestingly, our analyses hint that Mystriosaurus may be more closely related to the Chinese teleosauroid (previously known as Peipehsuchus) than any European form. [ABSTRACT FROM AUTHOR]

In 2016, an extraordinary burial of a young adult individual was discovered at the Late Pre-Pottery Neolithic B (LPPNB, 7,500–6,900 BCE) settlement of Baʻja in southern Jordan. This burial has exceptional grave goods and an elaborate grave construction. It suggests discussing anew reconstructions of early Neolithic social structures. In this article, we will summarize former theories on the emergence of leadership and hierarchies and present a multivariate model according to which anthropological and archaeological data of the burial will be analyzed. In conclusion, we surmise that early Neolithic hierarchization in southern Jordan was based on corporate pathways to power rather than self-interested aggrandizers. However, some aspects of the burial point to regional exchange networks of prestige goods, a trait considered characteristic of network based leadership. In line with anthropological and sociological research, we argue that pathways to power should be considered as relational processes that can be understood only when comparing traits of the outstanding person to her/his social environment. [ABSTRACT FROM AUTHOR]

We here describe the first fossil remains of a green lizard of the Lacerta group from the late Miocene (MN 13) of the Solnechnodolsk locality in southern European Russia. This region of Europe is crucial for our understanding of the paleobiogeography and evolution of these middle-sized lizards. Although this clade has a broad geographical distribution across the continent today, its presence in the fossil record has only rarely been reported. In contrast to that, the material described here is abundant, consists of a premaxilla, maxillae, frontals, parietals, jugals, quadrate, pterygoids, dentaries and vertebrae. The comparison of these elements to all extant green lizard species shows that these fossils are indistinguishable from Lacerta trilineata. Thus, they form the first potential evidence of the occurrence of this species in the Miocene. This may be also used as a potential calibration point for further studies. Together with other lizard fossils, Solnechnodolsk shows an interesting combination of survivors and the dawn of modern species. This locality provides important evidence for the transition of an archaic Miocene world to the modern diversity of lizards in Europe. In addition, this article represents a contribution to the knowledge of the comparative osteological anatomy of the selected cranial elements in lacertids. This study gives special emphasis to the green lizards, but new data are also presented for related taxa, e.g., Timon lepidus, Podarcis muralis or Zootoca vivipara. Although the green lizards include several cryptic species for which determination based on isolated osteological material would be expected to be difficult, our comparisons show several important morphological differences, although a high degree of variability is present. [ABSTRACT FROM AUTHOR]