Journal of Anatomy最新文献

{"title":"Functional compartmentalization of the anconeus: A three-dimensional study of muscle morphology and innervation patterns","authors":"Jocelynn G. McGee,&nbsp;Catherine Amara,&nbsp;John Tran,&nbsp;Anne M. R. Agur","doi":"10.1111/joa.70154","DOIUrl":"10.1111/joa.70154","url":null,"abstract":"<p>The function of the anconeus has been previously described for the muscle as a whole. No studies were found that explored the functional neuromuscular partitioning based on 3D muscle architecture and innervation patterns, which is paramount to understanding changes in pathological muscle. The purpose of this study was to investigate 3D muscle morphology and intramuscular innervation of the anconeus, quantify architectural parameters, and propose functional implications of the findings. The fiber bundles, aponeuroses, and intramuscular innervation of the anconeus (<i>n</i> = 8 embalmed specimens, mean age 81 ± 12 years) were serially dissected, digitized, and modeled in 3D. Muscle morphology and intramuscular innervation patterns were determined and architectural parameters computed. The 3D models and data were used to assess muscular partitioning and propose functional implications of the findings. The anconeus was found to be morphologically partitioned into three parts, proximal, distal, and deep, based on fiber bundle orientation, attachment sites, and architectural parameters. The nerve to anconeus supplied the proximal part and underlying deep part. The nerve bifurcated to supply the distal part via medial and lateral branches or superficial and deep branches. In conclusion, the proximal part could act as an abductor of the ulna, the distal part as an initial elbow extensor, and deep part as a stabilizer and tensor of the elbow joint capsule. The in-depth 3D mapping of the anconeus will enable the development of in vivo ultrasound protocols to provide further insight into the in vivo functions of the three parts of the anconeus.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"1120-1129"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13398567/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147690346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Updating the forelimb anatomy of the domestic cat (Felis catus, Felidae) based on evolutionary inferences of its muscles and nerves I: Shoulder and brachium","authors":"Juan Fernando Vélez García,&nbsp;Ismael Vélez Cabrera,&nbsp;Maria Angelica Miglino","doi":"10.1111/joa.70151","DOIUrl":"10.1111/joa.70151","url":null,"abstract":"&lt;p&gt;The domestic cat (&lt;i&gt;Felis catus&lt;/i&gt;) is a species of the order Carnivora, suborder Feliformia, and family Felidae. It is used as a representative model of mammals in comparative anatomy of vertebrates, whereas in veterinary anatomy, only differences from the domestic dog are described. Because of this, several recent studies on thoracic limb muscles in wild felids have preferred the use of former references concerning the anatomy of the cat as a guide to describe their findings. Furthermore, these studies established the homologies of the thoracic limb muscles among felids based on topology but did not consider other evolutionary characteristics, such as innervation and embryological development. Therefore, the present study aimed to describe in detail the thoracic limb muscles and the brachial plexus of &lt;i&gt;F. catus&lt;/i&gt; to reconstruct muscle maps, report anatomical variants, establish homologies, and infer muscle derivations in felids. In this chapter, we report the attachments, innervation, and arterial supply of the intrinsic shoulder and brachium muscles and the origin and distribution of the brachial plexus of &lt;i&gt;F. catus&lt;/i&gt; in these regions. Nineteen thoracic limbs from 10 carcasses of &lt;i&gt;F. catus&lt;/i&gt; were used. Differences from other studies in &lt;i&gt;F. catus&lt;/i&gt; and other felids were observed when considering the topology, innervation, and most recent available literature on the embryonic muscle splitting patterns in amniotes. Among the main findings, we observed the articularis humeri muscle in only one limb (1/19), exhibiting the arrangement of an atavistic muscle, similar to the coracobrachialis longus muscle observed in six limbs (6/19) and the caput breve of biceps brachii muscle observed in two limbs (2/19). The triceps brachii muscle only has four heads, and the anconeus medialis muscle (named by other authors as the short portion of the caput mediale, caput mediale accessorium, or m. epitrochleoanconeus) is not part of the triceps brachii muscle since its attachments are independent, the ulnar nerve innervates it, and the most recent embryological derivation evidence in mammals supports it. Two tricipital bursae were observed between the tendons of the triceps brachii heads. The muscle maps on the thoracic limb bones were reconstructed and complemented with the anatomical relationships of the ligaments, joint capsules, synovial bursae, and nerves. Most studied brachial plexuses originated from C6-T1 (13/16), whereas the origin from C5 was observed bilaterally in two limbs and from T2 in one limb. Adding the results of other studies (56), the contributions from C5 or T2 were 4.17% (3/72) and 1.39% (1/72), respectively. The distribution of the brachial plexus nerves of &lt;i&gt;F. catus&lt;/i&gt; was similar to that reported in other studies in felids, although most of those studies did not report innervation to the anconeus medialis muscle. The nerve distribution and muscle topology allowed us to establish muscle homologies with other felids ","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"1138-1169"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13398976/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative histological analysis of vertebrates reveals Triassic climate variability across southern Pangea","authors":"Valerie Trinidad,&nbsp;Darlington Munyikwa,&nbsp;Michel Zondo,&nbsp;Timothy J. Broderick,&nbsp;Sterling J. Nesbitt,&nbsp;Stephen Tolan,&nbsp;Christopher Griffin","doi":"10.1111/joa.70159","DOIUrl":"10.1111/joa.70159","url":null,"abstract":"<p>Climate highly influenced the distribution of major animal groups that emerged during the Triassic throughout the supercontinent Pangea. The earliest dinosaurs and associated assemblages (Carnian Stage, Late Triassic, ~230 Ma) are recovered along a paleolatitudinal climate belt spanning southern Pangea. However, developmental responses of different amniotic clades to climate across these environments remain unknown. Characterizing developmental variability, presumably driven in part by climatic variability within this belt, helps constrain the climatic ranges that shaped the earliest dinosaurs prior to their worldwide dispersal, while also providing insights into developmental plasticity of Triassic fauna. We analyzed the bone histology of five vertebrate taxa from the Carnian of Zimbabwe, including sauropodomorph and herrerasaurid dinosaurs, a gomphodontosuchine cynodont, a hyperodapedontine rhynchosaur, and a suchian archosaur (?aetosaur) as a proxy to assess probable climatic influence by comparing various growth strategies/metabolisms of these clades across southern Pangea. The dinosaurs are continuously growing individuals that exhibit well-vascularized woven-parallel and parallel-fibered cortical bone with no apparent growth marks. The cynodont is an immature specimen with a well-vascularized fibrolamellar matrix that has anastomosing vascular canals throughout the cortex and a single growth mark, indicating rapid growth. The rhynchosaurian femur and suchian tibia show moderate to poorly vascularized parallel-fibered and woven-fibered matrixes possessing multiple lines of arrested growth along with an external fundamental system, suggesting these were slow-growing individuals that had reached skeletal maturity at the time of death. Comparing this histology to that of similar assemblages from current-day Brazil, Argentina, and India (which fell along the same paleolatitudinal zone during the Triassic), the mid-continent (i.e., Zimbabwean) dinosaurs exhibit continuous uninterrupted growth in contrast to other histologically sampled dinosaurs from different localities along this climatic belt, whereas the Zimbabwean rhynchosaur and suchian exhibit patterns with more frequent cessation of growth than their South American counterparts. Slower-growing Zimbabwean taxa—presumably, more susceptible to climatic stressors—exhibit characteristics suggestive of a less resource-rich environment (e.g., frequent cessations, more interrupted growth) compared with rhynchosaurs and aetosaurs from South America. Taxa with faster growth rates and higher metabolic regimes (i.e., dinosaurs, cynodont) from this same assemblage apparently grew rapidly—and roughly continuously—throughout the year. This is consistent with an overall more arid but less seasonal climate in Zimbabwe compared to the signals recovered in Brazil, Argentina, and India.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"989-1004"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13398563/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147771805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A bristle-nosed Jurassic ray-finned fish (Actinopterygii) bears true dermal odontodes on its snout","authors":"Jack Stack,&nbsp;Ben T. Kligman,&nbsp;Maranda L. Stricklin","doi":"10.1111/joa.70152","DOIUrl":"10.1111/joa.70152","url":null,"abstract":"<p>Comparison of shared morphological characteristics between living and extinct species is essential to reconstructing repeated phenotypic evolution in deep time. For example, the extinct Triassic–Jurassic redfieldiid ray-finned fishes possess tubercles on their snout which resemble the enlarged dermal odontodes that give some extant ray-finned fishes “bristly” snouts. The three-dimensional anatomy of redfieldiid snout tubercle-bearing bones is typically obscured in fossils, leaving the anatomical identity and homology of these snout tubercles uncertain. We describe new aspects of redfieldiid snout tubercles based on a recently collected, exceptionally well-preserved specimen (VMNH 129827) of †<i>Redfieldius gracilis</i> from lacustrine deposits of the Early Jurassic (Hettangian, ~201 million years old) Waterfall Formation of the Culpeper Basin (Newark Supergroup) of Virginia. We determine that the body and skull of †<i>Redfieldius</i> is covered with dermal odontodes, which are extended into bristle-like tubercles on the snout and orbit. The phylogenetic position of †<i>Redfieldius</i> outside of the teleostean total group indicates that redfieldiid snout tubercles evolved convergently from those in living fishes, such as the bristlenose catfish (<i>Ancistrus</i>) and the denticle herring (<i>Denticeps</i>). †<i>Redfieldius</i> does not have strong morphological overlap with extant snout tubercle-bearing ray-finned fishes, limiting inference of their ecological function. However, we posit that the snout tubercles of †<i>Redfieldius</i>, in concert with a covering of pointed dermal odontodes on the scales, may have served a defensive function. The enlarged snout tubercles in †<i>Redfieldius</i> are part of an emerging pattern of increasingly specialized tooth morphology in Late Triassic–Early Jurassic ray-finned fishes that mirrors living ray-finned fishes.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"1021-1032"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13398942/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147698775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Labiolingual thickness and cross-sectional area in callitrichid incisors","authors":"Keegan R. Selig","doi":"10.1111/joa.70162","DOIUrl":"10.1111/joa.70162","url":null,"abstract":"<p>Several species of primate rely on tree exudates as a component of their diet, with taxa ranging from opportunistic exudativores to intensive exudativores. To access these exudates, many taxa make use of modified anterior teeth to gouge into tree bark to stimulate the flow of saps or gums. Recent efforts have identified several “dental signatures” of exudativory among primates, including differences in the robustness and bending resistance of the strepsirrhine toothcomb. The relative size and the labiolingual thickness of the lower incisors have also been cited as a difference between gouging and non-gouging callitrichids, with the former predicted to have relatively larger (in cross-sectional area) and labiolingually thicker lower incisors. However, along with methodological issues, these predictions have generally only been tested in a small sample of callitrichid taxa. Here, these predictions are tested in a sample of seven extant callitrichid species (<i>N</i> = 185 specimens), representing five genera. The results suggest that gouging callitrichids are not characterized by relatively larger incisors, contrary to previous results. However, the gougers are characterized by labiolingually thicker lower incisors compared to the non-gougers, which hypothetically helps resist bending stress during gouging. Having relatively taller incisors, as well as more highly decussated enamel, larger tooth roots, and differences in enamel distribution, along with the labiolingually thicker lower incisors may explain why the gouging taxa are not characterized by relatively larger incisors. This pattern of incisor morphology serves as another signal for primate gouging and may provide insight into gouging behavior in the fossil record and other extant taxa such as the exudativorous lorisoids.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"1112-1119"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13398778/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147771881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A statistical shape model of the human female sacrum: An integrative analysis of form","authors":"Liesbeth Van Hauwermeiren,&nbsp;Emmanuel Audenaert,&nbsp;Jan Van Houcke,&nbsp;Harold Matthews,&nbsp;Peter Claes,&nbsp;Louke Delrue,&nbsp;Eric Achten,&nbsp;Dominique Adriaens,&nbsp;Tom Van Hoof","doi":"10.1111/joa.70148","DOIUrl":"10.1111/joa.70148","url":null,"abstract":"<p>Sacral shape has been investigated in the context of many disciplines, such as anthropology, forensics and in clinical contexts. The female population is of special interest, given the complex interaction between locomotor, thermoregulatory and obstetric demands on the pelvis. However, interpretation of results between current studies is limited by the use of a diverse range of parameters, often offering an oversimplified and fragmented view on sacral shape. We investigated sacral shape in a young adult female population between 18 and 40 years old, using a statistical shape model based on 109 3D CT datasets and principal component analysis. This study provides a comprehensive and visually intuitive view on sacral shape, describing general shape patterns and covariation between different regions of the sacrum. Two dominant shape components were sacral size and sagittal curvature. Both components were associated with specific shape variations in the load-bearing areas of the sacrum, indicating a relationship between shape and function. This study generates hypotheses on sacral shape and its relation to function that warrant further research.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"1050-1067"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147771508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the microstructure of simple rhamphothecae in chickens (Aves: Galliformes: Gallus gallus domesticus)","authors":"Khanh H. T. To,&nbsp;Michelle R. Stocker,&nbsp;Tobin L. Hieronymus","doi":"10.1111/joa.70147","DOIUrl":"10.1111/joa.70147","url":null,"abstract":"<p>Corneous sheaths on the jaws of beaked tetrapods, or rhamphothecae, are classified as simple or compound based on their external morphology. In birds, simple rhamphothecae possess single corneous sheaths covering the upper jaws and the mandibles, respectively, rather than the several corneous plates of compound rhamphothecae. More than 60% of modern birds have simple rhamphothecae, but not all birds with simple rhamphothecae use their beaks for the same feeding style or dietary preferences. Grossly similar simple rhamphothecae may possess unreported microanatomical differences in response to different functional demands, but this requires first exploring whether the microanatomy of simple rhamphothecae is homogenous. We hypothesized based on foraging biomechanics that the rostral portion of the rhamphotheca is more mechanically resistant than the caudal portion, and the microanatomy will reflect this. We examine the microanatomy and biomechanical properties of rhamphothecae using chickens (<i>Gallus gallus domesticus</i>). We map the microstructure and relative hardness of corneous materials throughout the rhamphotheca using plastic-embedded histology and microindentation. Histological sections reveal eight corneous regions, more numerous on the rostral portion of the beak, making up the seemingly continuous corneous sheath of the upper jaws and mandibles. Microindentation of individual regions reveals hardness differences, with the rostral rhamphothecal tomia (cutting edge) having the highest hardness, and layers comprising the caudal portion of the rhamphotheca having the lowest. This configuration shows that more resistant corneous layers are found rostrally to accommodate the mechanical interactions happening at the tip. Our study shows that unreported complexity within simple beaks will allow us to determine simple rhamphotheca diversity and address the homoplasy of simple rhamphothecae in modern birds.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"1099-1111"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13399307/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147592214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Post-hatching development of the remote-tactile bill-tip organ in precocial shorebirds (Scolopacidae)","authors":"Carla J. du Toit,&nbsp;Anyaise Green,&nbsp;Daniel J. Field","doi":"10.1111/joa.70149","DOIUrl":"10.1111/joa.70149","url":null,"abstract":"<p>Several groups of birds that rely on tactile foraging methods to locate prey exhibit specialized bill-tip organs to sense tactile cues. Most scolopacid shorebirds (sandpipers and kin) employ the sensory capability of remote-touch during foraging, allowing them to locate buried prey at a distance from their bills by detecting vibrational cues in the substrates they probe in. This is facilitated by a bill-tip organ made up of dense clusters of mechanoreceptors housed within a constellation of neurovascular foramina in the bone at the tips of their bills. Bill-tip organ morphology has been shown to correlate with foraging ecology; however, all previous research has focused on adult birds. Many tactile foraging birds, including scolopacids, have precocial young that forage independently within hours of hatching, yet remote-touch foraging and its morphological correlates in juvenile birds remain unexplored. Here, we use μCT scans to describe the morphology of the bill tips of juvenile–adult pairs of several scolopacid species to characterize the post-hatching development of the bill-tip organ. We show that the osteological correlates of functional bill-tip organs are present in juvenile scolopacids and describe changes in bill-tip organ morphology during post-hatching development. Our results suggest that juvenile scolopacids, and likely other precocial tactile foraging birds, are able to sense tactile cues with their bills from the point of hatching. Our data additionally suggest that previously described interspecific variation in bill-tip organ morphology associated with taxon-specific foraging behaviours and habitat preferences appears to develop after fledging and dispersal in scolopacids. These data reveal ontogenetic and interspecific differences in scolopacid bill-tip organ morphology associated with differing ecologies and improve our understanding of foraging behaviour of juvenile shorebirds.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":"249 5","pages":"1087-1098"},"PeriodicalIF":2.2,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13398562/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147633450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Taxonomic and ecological assessment of an Antarctic Eocene Folivora (Mammalia) metacarpal using three-dimensional geometric morphometrics.","authors":"Bruno Quaggia, Javier N Gelfo, Carolina Acosta Hospitaleche","doi":"10.1111/joa.70245","DOIUrl":"10.1111/joa.70245","url":null,"abstract":"<p><p>Here, we reassess the taxonomic affinities and functional morphology of TMM 44190-1, an isolated metacarpal II from the Eocene La Meseta Formation, Marambio (Seymour) Island, Antarctic Peninsula, previously referred to an indeterminate xenarthran. We evaluated its morphological similarities using three-dimensional geometric morphometrics. A principal component analysis, based on a sample of 50 metacarpals representing 38 taxa, including Paleogene terrestrial mammals from Antarctica and South America, as well as extant mammals exhibiting a wide range of terrestrial locomotor habits, was conducted. Additionally, TMM 44190-1 was compared with Eocene taxa from Antarctica and South America, including Gondwanatheria, Metatheria (Sparassodonta, Pucadelphyidae, and Didelphimorphia), South American native ungulates (Astrapotheria, Litopterna, Xenungulata, and Notoungulata), and Xenarthra (Cingulata and Pilosa). Both geometric morphometric and qualitative anatomical evidence consistently support the previous assignment of TMM 44190-1 to Xenarthra and further allow a more precise taxonomic placement, identifying the specimen as an indeterminate Folivora.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13639325/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149110043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cochlear morphology is correlated with endocranial volume in catarrhine primates.","authors":"Takumi Kojima, Naoki Morimoto","doi":"10.1111/joa.70242","DOIUrl":"https://doi.org/10.1111/joa.70242","url":null,"abstract":"<p><p>The cochlear dimensions relevant to hearing capability generally follow a pattern of allometric scaling with body mass in mammals. Nevertheless, humans exhibit cochlear dimensions larger than expected from the body mass, and it has been proposed that this is related to encephalization. In this study, we investigate whether the link between brain mass and cochlear morphology is unique to humans and whether cranial features other than brain mass impinge on the cochlear morphology in catarrhine primates that exhibit considerable variation in brain mass. Cochlear and cranial dimensions (cochlear length, oval window area, endocranial volume, cranial size, and interaural distance) were measured on three-dimensional surface models for 30 hominoid individuals (humans, chimpanzees, gorillas, orangutans, and gibbons) and 20 cercopithecine individuals (Japanese macaques, mandrills, and baboons). Relations between cochlear and cranial variables were evaluated using generalized linear mixed model (GLMM) and phylogenetic generalized least squares (PGLS) analyses. The endocranial volume better predicts cochlear morphology than the other cranial measurements in catarrhines. Specifically, the average cochlear length per turn exhibits a strong correlation, while the oval window area exhibits a weaker correlation with the endocranial volume in both GLMM and PGLS. Humans do not deviate from the common allometric pattern of cochlear length against endocranial volume in the catarrhine primates studied here. It appears that humans do not necessarily represent an exceptional cochlear morphology in catarrhine primates after accounting for the cranial dimensions and phylogeny. Our data thus indicate that the link between endocranial volume and cochlear morphology could be a more general pattern for catarrhine primates than previously recognized.</p>","PeriodicalId":14971,"journal":{"name":"Journal of Anatomy","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633437/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149110090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}