Anatomical Record最新文献

{"title":"Helmeted hornbill cranial kinesis: Balancing mobility and stability in a high-impact joint.","authors":"Mike Schindler, Benjamin Flaum, Armita Razieh Manafzadeh, Viktoriia Kamska, Kanmani Chandra Rajan, Maria Jose Robles Malagamba, Ruien Hu, Daniel Baum, Mason N Dean","doi":"10.1002/ar.25613","DOIUrl":"https://doi.org/10.1002/ar.25613","url":null,"abstract":"<p><p>Prokinesis-in which a craniofacial joint allows the rostrum to move relative to the braincase-is thought to confer diverse advantages in birds, mostly for feeding. A craniofacial joint would, however, be a weak link if cranial stability is important. Paradoxically, we have identified a craniofacial joint in helmeted hornbills (Rhinoplax vigil), birds known for violent head-butting behavior. To understand how the helmeted hornbill balances the competing demands of kinesis and collision, we combine manual craniofacial joint manipulation, skull micro-computed tomography (μCT) and articular raycasting, also comparing our data with μCT scans of 10 closely-related species that do not aggressively head-butt. The helmeted hornbill boasts a particularly massive casque, a distinctive upper mandible protrusion fronting the braincase; the craniofacial joint is immediately caudal to this, a standard prokinetic hinge joint position, at the dorsal border of braincase and upper mandible. However, whereas the craniofacial joint in all bucerotiform bird species we examined was only a slender bridge, the helmeted hornbill's joint is exceptionally reinforced. Raycasting analyses revealed high correspondence between the extremely broad joint facets, with reciprocal topographies of braincase and casque fitting like complex puzzle pieces. The result is a joint with a single degree of freedom and limited range of motion, increasing the gape when elevated, but conversely stable when depressed. With the dense network of bony trabeculae in the casque also funneling back to this joint, we infer that the damaging effects of high cranial impact are mitigated, not by dissipating impact energy, but through a skull architecture with a prodigious safety factor.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143538073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early life functional transitions impact craniofacial morphology in osteogenesis imperfecta.","authors":"Courtney A Miller, Tanusha Emanuel, Rachel A Menegaz","doi":"10.1002/ar.25640","DOIUrl":"https://doi.org/10.1002/ar.25640","url":null,"abstract":"<p><p>Early life behaviors have a profound role in shaping adult craniofacial morphology. During early life, all mammals undergo the dynamic transition from suckling to mastication, a period coinciding with rapid cranial biomineralization. Osteogenesis imperfecta (OI), a genetic disorder that impacts the production of type I collagen, disrupts biomineralization, leading to craniofacial growth differences affecting quality of life. This study investigates craniofacial development during infant oral motor developmental stages in OI mice compared to unaffected wild-type littermates (WT mice). We hypothesize OI mice will exhibit smaller overall size, and the adult OI phenotype will develop postnatally in response to masticatory loading. Point cloud and fixed landmarks were collected from micro-computed tomography scans, then geometric morphometric analyses and interlandmark distances (ILDs) compared craniofacial size and shape between OI and WT mice at birth (P0; n = 27 OI murine/20 WT) and postnatal Days 7 (P7; n = 21/21), 14 (P14; n = 16/20), 21 (P21; n = 20/26), and 28 (P28; n = 26/33). This study found no size and shape differences between genotypes at birth. Starting at P7, OI mice are significantly (p < 0.05) smaller and display pronounced shape changes (p < 0.001) characterized by a larger neurocranium and a shorter viscerocranium. At P21, significant differences emerge in cranial base orientation, neurocranial width, viscerocranial shortening, and zygomatic arch displacement. These findings underscore the importance of early life oral motor stages in developing the adult OI craniofacial phenotype and oral health, suggesting earlier craniofacial interventions may improve effective treatment of OI.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143484584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The osteology, taxonomy, and phylogenetic placement of Seeleyosaurus guilelmiimperatoris (Plesiosauroidea, Microcleididae) from the Lower Jurassic Posidonia Shale of Germany.","authors":"Sven Sachs, Daniel Madzia, Miguel Marx, Aubrey J Roberts, Oliver Hampe, Benjamin P Kear","doi":"10.1002/ar.25620","DOIUrl":"https://doi.org/10.1002/ar.25620","url":null,"abstract":"<p><p>Seeleyosaurus guilelmiimperatoris is an early-diverging plesiosauroid from the lower Toarcian (Lower Jurassic) of the Posidonienschiefer Formation (Posidonia Shale) of Holzmaden, southwestern Germany. It is known from almost complete skeletons of two osteologically mature individuals, the holotype and a referred specimen that was largely destroyed during World War II. Although well-preserved and substantially complete, the anatomy of Seeleyosaurus and its taxonomic and phylogenetic significance remain insufficiently understood. Here, we provide a complete osteological description of the taxon. Seeleyosaurus guilelmiimperatoris can be diagnosed based on a unique combination of characters, including one autapomorphy: the tall and basally constricted neural spines of the posterior cervical, pectoral, and dorsal vertebrae which have a sinusoidal shape in lateral view. Our study supports the validity of the plesiosauroid taxon Plesiopterys wildi, which was considered a junior synonym of Seeleyosaurus in a previous joint assessment of the taxa. Our phylogenetic evaluation places S. guilelmiimperatoris among Microcleididae, in congruence with previous studies. However, in contrast to earlier phylogenetic reconstructions, our analyses, which take into account numerous changes to the character matrix, reconstruct S. guilelmiimperatoris as falling within the Microcleidus clade. While we admit that Seeleyosaurus might potentially be considered a species of Microcleidus, we refrain from promoting this nomenclatural change pending an osteological and taxonomic reassessment of Microcleidus spp. as well as other, potentially closely related forms, such as Lusonectes sauvagei.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143469967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphology and function of pinniped necks: The long and short of it.","authors":"Justin Keller, Annalisa Berta, Mark Juhn, Blaire Van Valkenburgh","doi":"10.1002/ar.25642","DOIUrl":"https://doi.org/10.1002/ar.25642","url":null,"abstract":"<p><p>Terrestrial vertebrates from at least 30 distinct lineages in both extinct and extant clades have returned to aquatic environments. With these transitions came numerous morphological adaptations to accommodate life in water. Relatively little attention has been paid to the cervical region when tracking this transition. In fully aquatic cetaceans, the cervical vertebrae are compressed, largely because a loss of neck mobility reduces drag. We ask whether this pattern of cervical evolution is present in the more recently evolved semiaquatic pinnipeds. Here, we compare neck morphology and function in three families of pinnipeds, the Otariidae, Phocidae, and Odobenidae as well as between pinnipeds and their terrestrial arctoid relatives (ursids and mustelids). Using cranial CT scans, we quantified the occipital surface area for neck muscle attachment as well as vertebral size and shape using linear measurements. Results show that pinnipeds have a relatively larger occipital surface area than ursids and terrestrial mustelids, suggesting that marine carnivorans have enlarged their neck muscles to assist with head stabilization during swimming. Within pinnipeds, we found quantitative differences in cervical morphology between otariids and phocids that coincide with their locomotor style. Phocids are hindlimb-dominated swimmers that propel themselves with pelvic oscillations. Their necks are relatively stiff and their cervical vertebrae are compressed anteroposteriorly with reduced muscular attachment areas. By contrast, otariids are forelimb-dominated swimmers that locomote in water and on land using their pectoral limbs, often recruiting their neck to initiate turns underwater as well as assisting in \"walking\" on land. Consequently, otariids have stronger, more flexible necks than phocids, which is reflected in more elongate cervical vertebral centra with larger muscle attachments. The walrus (Odobenidae) has a cervical vertebrae morphology intermediate to that of phocids and otariids, consistent with a phocid swimming mode combined with a more muscular neck that likely functions in intraspecific conflict and haul-out behavior.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143469964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of the anatomical basis for predicting plutonium alpha particle radiation induced osteogenic cancers.","authors":"Scott C Miller","doi":"10.1002/ar.25641","DOIUrl":"https://doi.org/10.1002/ar.25641","url":null,"abstract":"<p><p>Plutonium was discovered and first synthesized in the early 1940's. Several isotopes of plutonium are used in nuclear technologies, ²³⁸Pu for heat generation and ²³⁹Pu for energy production and weapons. Both isotopes emit alpha particles, which pose a significant radiation hazard when incorporated into the body. Alpha particles emitted during ²³⁹Pu decay deposit energy along a very short path in biological tissues (≈45 μm in soft tissues). Thus, defining the anatomical locations of these deposits is essential to identify the cells at risk of radiation damage and potential malignant transformation. Bone is a primary site for plutonium deposition and retention. Plutonium exposures are associated with increases in osteogenic cancers. Plutonium is preferentially deposited on endosteal and endocortical bone surfaces, particularly those surrounded by red versus yellow bone marrow. Red marrow is more vascularized with a sinusoid network, while yellow marrow is largely a closed capillary system. Cancellous bone in red marrow sites has greater bone turnover rates and relatively more plutonium-related bone cancers than in yellow marrow sites. The relationships of plutonium deposits in bone and potential alpha particle exposures to cells that include osteoclasts, reversal cells, canopy cells, osteoblasts, bone lining cells, and osteogenic progenitors of the basic multicellular unit during bone modeling and remodeling are reviewed. Differences in distributions of ²³⁹Pu versus naturally occurring tumors in humans and experimental animals are noted. This review emphasizes the importance of the anatomical locations of plutonium deposition and retention in the skeleton and the potential relative radiation risks from alpha particles to bone cells and their progenitors.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143442685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Human interparietal bones: Examination of existing classification schemes and development of a graphic library depicting variations.","authors":"Melissa D Clarkson, Rhian R Dunn, Joseph T Hefner, Holly A Long, Micayla C Spiros","doi":"10.1002/ar.25643","DOIUrl":"https://doi.org/10.1002/ar.25643","url":null,"abstract":"<p><p>Due to its complex ossification during development, the superior region of the human occipital bone is a frequent site of supernumerary bones known as interparietal bones. Interparietal bones have been extensively studied across various disciplines, resulting in multiple classification schemes using icon-like graphics to represent categories of interparietal variants. However, disparities across these classification schemes reveal the need for a standardized system to facilitate comparisons and permit data pooling across studies. Based on an extensive literature review and the examination of physical specimens, a graphic library of 80 evidence-based graphics capturing interparietal variants was designed for community use. It provides five graphics of different morphologies of the lambdoid suture, 64 graphics of interparietal bones, six of ossicles at lambda, three of mendosal suture variants, and two of intrasutural ossicles. This approach allows additional graphics to be added in the future as needed. Graphics are compared to those from existing classification schemes and an exercise using the graphics to classify crania was performed. In the broadest sense, this research establishes a model for improved practices in representing and sharing morphological data.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143426598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and thickness of Glisson's capsule differ considerably on the liver surface in mammalian species.","authors":"Hiroki Uchida, Naoyuki Aihara, Toshifumi Morimura, Shoma Matsumoto, Daichi Hasegawa, Tomoko Ichiki, Eiichi Okamura, Masanaga Muto, Go Sugahara, Toshio Miki, Masatsugu Ema, Kenichi Watanabe, Junichi Kamiie, Kinji Asahina","doi":"10.1002/ar.25636","DOIUrl":"https://doi.org/10.1002/ar.25636","url":null,"abstract":"<p><p>Glisson's sheath is the connective tissue ensheathing the portal vein, hepatic artery, and bile duct within the liver. Although the connective tissue surrounding the liver surface is known as Glisson's capsule, its structure and function are poorly understood. In the present study, we analyzed mouse, rat, rabbit, feline, canine, monkey, porcine, bovine, and equine livers by histochemistry and immunohistochemistry analysis of α-smooth muscle actin, keratin 19, and podoplanin and examined how the structure of the Glisson's capsule is conserved and differs among the nine species. Glisson's capsule tended to thicken as the animal's body size increased. Among the nine mammalian species, bile ducts were observed adjacent to the connective tissue of Glisson's capsule in adult monkey, porcine, bovine, and equine livers without association with portal veins. Fetal monkey and porcine livers exhibited thin Glisson's capsules without bile duct development. The hepatic artery develops in the Glisson's capsule in adult canine, monkey, porcine, bovine, and equine livers without association with the bile ducts and portal veins. Similar to the human liver, the livers of adult monkeys develop lymphatic vessels beneath the liver surface. The present study reveals for the first time that the structure of the Glisson's capsule differs considerably between small (mouse, rat, rabbit, and cat) and large (monkey, pig, cattle, and horse) animals and that the dog exhibits an intermediate structure between the two groups.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143383917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Segmentation of cortical bone, trabecular bone, and medullary pores from micro-CT images using 2D and 3D deep learning models.","authors":"Andrew H Lee, Julian M Moore, Brandon Vera Covarrubias, Leigha M Lynch","doi":"10.1002/ar.25633","DOIUrl":"https://doi.org/10.1002/ar.25633","url":null,"abstract":"<p><p>Computed tomography (CT) enables rapid imaging of large-scale studies of bone, but those datasets typically require manual segmentation, which is time-consuming and prone to error. Convolutional neural networks (CNNs) offer an automated solution, achieving superior performance on image data. In this methodology-focused paper, we used CNNs to train segmentation models from scratch on 2D and 3D patches from micro-CT scans of otter long bones. These new models, collectively called BONe (Bone One-shot Network), aimed to be fast and accurate, and we expected enhanced results from 3D training due to better spatial context. Contrary to expectations, 2D models performed slightly better than 3D models in labeling details such as thin trabecular bone. Although lacking in some detail, 3D models appeared to generalize better and predict smoother internal surfaces than 2D models. However, the massive computational costs of 3D models limit their scalability and practicality, leading us to recommend 2D models for bone segmentation. BONe models showed potential for broader applications with variation in performance across species and scan quality. Notably, BONe models demonstrated promising results on skull segmentation, suggesting their potential utility beyond long bones with further refinement and fine-tuning.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143191288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bienotheroides wucaiensis sp. nov., a new tritylodontid (Cynodontia, Mammaliamorpha) from the Late Jurassic Shishugou Formation of Xinjiang, China.","authors":"Jiawen Liu, Xing Xu, James M Clark, Shundong Bi","doi":"10.1002/ar.25631","DOIUrl":"https://doi.org/10.1002/ar.25631","url":null,"abstract":"<p><p>The Shishugou Formation of the Middle to Late Jurassic in Xinjiang, China, has produced abundant tetrapod fossils including dinosaurs and tritylodontids. Bienotheroides is a genus of highly specialized tritylodontids, characterized by a short and wide snout, ventrally expanded zygomatic process, strongly reduced maxilla, short and flat basisphenoid, and maxillary teeth cusp formula 2-3-3. Here, we report a new tritylodontid, Bienotheroides wucaiensis sp. nov. from the lower Upper Jurassic level of the formation at Wucaiwan, Xinjiang, Northwest China, represented by a well-preserved cranium and associated postcranial skeleton. Micro-computed tomography and 3D reconstruction reveal the medial view of the cranial structure and the replacement upper incisors, providing new anatomical information of Bienotheroides. The absence of a septomaxilla in B. wucaiensis reveals the homoplastic evolution of this feature within tritylodontids, as it remains in basal mammaliaforms but is lost in later descendants.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143191226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Small fish, large variation: Morphological diversity of Weberian apparatus in Noturus catfishes and ecological implications.","authors":"J C Hoeflich, Juan Liu","doi":"10.1002/ar.25629","DOIUrl":"https://doi.org/10.1002/ar.25629","url":null,"abstract":"<p><p>The Weberian apparatus is a hearing specialization unique to the otophysan fishes, and an unexpected degree of morphological variation exists in species of the Noturus catfishes. Our aim in this study is to investigate relationships between morphological variations and ecology that may drive this variation. Sampling 48 specimens representing 25 species, we investigated morphological diversity and accounted for ecological variables using landmark-based 3D geometric morphometrics and x-ray-based computed tomography (CT) images. We tested five ecological variables using three landmark sets in three focused regions: the tripus, scaphium, and overall shape of the peripheral structures including the complex vertebra. We performed phylogenetic signal tests, and phylogenetic influence is not significant within Noturus in any of the three regions. Among the tested ecological variables, stream velocity and coloration (a proxy for substrate) were found to be significantly associated with the morphology of the tripus and scaphium, the first and the last ossicles of the sound transmitting chain. This eco-morphology connection may be mediated through stream velocity's dominant role in defining the soundscape of aquatic environments and substrate material properties contributing to which sounds are produced and propagated. We conclude that Noturus catfishes could be acoustically adapted to their microhabitats.</p>","PeriodicalId":50793,"journal":{"name":"Anatomical Record","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143015268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}