Journal of Morphology最新文献

{"title":"Discovery and characterization of a transient chaetal gland during the development of Capitella teleta (Sedentaria: Annelida)","authors":"Ekin Tilic,&nbsp;Thomas Bartolomaeus,&nbsp;Elaine C. Seaver","doi":"10.1002/jmor.21742","DOIUrl":"https://doi.org/10.1002/jmor.21742","url":null,"abstract":"<p>Chaetae are among the most extensively studied structures in polychaetes, serving as a defining morphological trait for annelids. <i>Capitella teleta</i> stands out as one of the few established annelid models for developmental and morphological studies, thus receiving significant scholarly attention. In this study, we unveil a previously unnoticed glandular structure associated with chaetae within the larvae of <i>C. teleta</i>. Our investigations demonstrate the absence of comparable structures in the chaetal follicles of adults and juveniles (older than 1 week), as well as during active chaetogenesis, underscoring the transient nature of these glands. This indicates that larval chaetal follicles transform into a gland that later disappears. Utilizing histology and transmission electron microscopy, we characterized these glands. Our findings underscore the diversity of chaetal ultrastructure in annelids and show that, even in well-studied species, novel morphological details can be found. We emphasize the importance of examining various life-history stages to capture such transient morphological features. This work lays a crucial morphological foundation and deepens our understanding of chaetae and chaetogenesis in <i>C. teleta</i>, paving the way for more accurate interpretations of future experimental studies on chaetogenesis in this species.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jmor.21742","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141245707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Respiratory internal kinematics of the tongue base and soft palate in obese minipigs with obstructive sleep apnea","authors":"Zi-Jun Liu,&nbsp;Mandee Yang,&nbsp;Meng-Zhao Deng,&nbsp;Mohamed Yehia Abdelfattah,&nbsp;Michael C. Baldwin,&nbsp;Edward M. Weaver","doi":"10.1002/jmor.21741","DOIUrl":"https://doi.org/10.1002/jmor.21741","url":null,"abstract":"<p>It is largely unknown how the tongue base and soft palate deform to alter the configuration of the oropharyngeal airway during respiration. This study is to address this important gap. After live sleep monitoring of five Yucatan and two Panepinto minipigs to verify obstructive sleep apnea (OSA), eight and four ultrasonic crystals were implanted into the tongue base and soft palate to circumscribe a cubic and square region, respectively. The 3D and 2D deformational changes of the circumscribed regions were measured simultaneously with electromyographic activity of the oropharyngeal muscles during spontaneous respiration under sedated sleep. The results indicated that both obese Yucatan and Panepinto minipigs presented spontaneous OSA, but not in three nonobese Yucatan minipigs. During inspiration, the tongue base showed elongation in both dorsal and ventral regions but thinning and thickening in the anterior and posterior regions, respectively. The widths showed opposite directions, widening in the dorsal but narrowing in the ventral regions. The soft palate expanded in both length and width. Compared to normal controls, obese/OSA ones showed similar directions of deformational changes, but the magnitude of change was two times larger in the tongue base and soft palate, and obese/OSA Panepinto minipigs presented 10 times larger changes in all dimensions of both the tongue base and the soft palate. The distance changes between the dorsal surface of tongue base and soft palate during inspiration increased in normal but decreased in obese OSA minipigs.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141245709","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":"Morphological adaptation of the tongue of okapi (Okapia johnstoni Artiodactyla, Giraffidae)—Anatomy, histology, and ultrastructure","authors":"Karolina Goździewska-Harłajczuk,&nbsp;Pavla Hamouzová,&nbsp;Joanna Klećkowska-Nawrot,&nbsp;Petr Čížek","doi":"10.1002/jmor.21743","DOIUrl":"10.1002/jmor.21743","url":null,"abstract":"<p>The aim of this study was to describe the morphology of the tongue of the okapi, and to compare the results with other ruminants including browsers, intermediates and grazers. The material was collected post-mortem from two animals from a Zoological Garden. The structure of the okapi tongue, focusing of the shape of the tongue, lingual surface, its papillae and lingual glands, was examined using gross morphology, light and polarized microscopy, and by scanning electron microscopy. The okapi tongue was characterized by dark pigmentation on the lingual dorsum (except lingual torus) and on the whole ventral surface. Two types of filiform papillae were observed, with additional, even 6–8 projections at their base. The round fungiform papillae were present at a higher density, up to 16/cm², on the ventro-lateral area of the lingual apex. Round and elongate vallate papillae were arranged in two parallel lines between the body and root of the tongue. Numerous taste buds were detected within the epithelium of their vallum, while fungiform papillae had sparse taste buds. A lack of foliate papillae was noted. Very small conical papillae, some lenticular in shape, were present on the lingual torus. Thick collagen type I fibers were dominant over collagen type III fibers in the connective tissue of the lingual papillae. The mucous acini units were dominant among lingual glands, indicating that the secretion of okapi lingual glands was mostly mucous. In many aspects, the tongue of okapi resembles the tongue of other ruminants. The specific lingual shape and lingual surface, together with the lingual glands, support the processing of plant food, such as young and soft leaves. Although okapi tongue is characterized by smaller conical papillae compared to other ruminants, its high number of vallate papillae is similar that found in other browsers, intermediate and grazers. Thus the number of gustatory papillae rather indicates that this feature is not related to the type of feeding.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141200093","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 of the pterothoracic musculature in Paraneoptera and its phylogenetic implication (Insecta: Neoptera)","authors":"Azuma Kawata,&nbsp;Naoki Ogawa,&nbsp;Kazunori Yoshizawa","doi":"10.1002/jmor.21712","DOIUrl":"10.1002/jmor.21712","url":null,"abstract":"<p>Although the monophyly of Paraneoptera (=hemipteroid orders or Acercaria, composed of Psocodea, Thysanoptera and Hemiptera) has been widely accepted morphologically, the results from molecular phylogenetic and phylogenomic analyses contradict this hypothesis. In particular, phylogenomic analyses provide strong bootstrap support for the sister group relationship between Psocodea and Holometabola, that is, paraphyly of Paraneoptera. Here, we examined the pterothoracic musculature of Paraneoptera, as well as a wide range of other neopterous insect orders, and analysed its phylogenetic implication. By using the synchrotron microcomputed tomography (µCT) and parsimony-based ancestral state reconstruction, several apomorphic conditions suggesting the monophyly of Paraneoptera, such as the absence of the <b>II/IIItpm7</b>, <b>IIscm3</b>, <b>IIIspm2</b> and <b>IIIscm3</b> muscles, were identified. In contrast, no characters supporting Psocodea + Holometabola were recovered from the thoracic muscles. These results provide additional support for the monophyly of Paraneoptera, together with the previously detected morphological apomorphies of the head, wing base, and abdomen.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141155296","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":"Assessing phenotypic variation and plasticity of endemic gastropods from thermal water refugia using complex morphometric techniques: A case study of Lake Pețea melanopsids","authors":"Sándor Gulyás,&nbsp;Pál Sümegi,&nbsp;Tamás Müller,&nbsp;Dana H. Geary,&nbsp;Imre Magyar,&nbsp;Balázs Nagy,&nbsp;Réka Benyó-Korcsmáros","doi":"10.1002/jmor.21739","DOIUrl":"https://doi.org/10.1002/jmor.21739","url":null,"abstract":"<p>Understanding the underlying reasons for phenotypic plasticity and resulting morphological disparity is one of the key topics of evolutionary research. The phenotypic plasticity of extant and fossil melanopsids has been widely documented. Yet millennial-resolution, well-dated records from small aquatic habitats harboring endemics are scarce. The thermal spring-fed Lake Pețea is an ice age refugia harboring a unique endemic warm-water fauna. Subfossil melanopsids display incredible morphological variability from smooth to keeled, elongated to ribbed, shouldered forms. Numerous morphotypes have been considered as individual taxa with a fluent succession from the smooth elongated to the ribbed, shouldered types. This study presents an extensive morphometric analysis of subfossil melanopsids (ca. 3500 specimens) derived from stratified samples with an independent chronology. The aim was to separate morphotypes for investigations of temporal morphological disparity. Our results challenge the widely accepted hypothesis that proposes the evolution of shouldered, compressed, ribbed shells through a two-step process from smooth elongated spindle-shaped shells. Instead, it suggests that the subfossil shells belong to two distinct taxa present throughout the available stratigraphic data. The main components of shape variation, shape globularity, and shell coiling seem allometry-related. Ribs, striation, and keels appear randomly. High-spired spindle-shaped forms were considered to represent specimens of <i>Microcolpia daudebartii hazayi</i>. Bulkier low-spired and shouldered specimens represent phenotypes of <i>Mi. parreyssii parreyssii</i>. The collective and random distribution of morphotypes from the early stages of the lake's history also refutes the idea of a continuous transformation of the elongated forms into compressed, shouldered ones. Rather points to multiple events and environmental stimuli triggering development. Melanopsids appear in Late Glacial horizons, with <i>Theodoxus prevostianus</i> preferring temperatures above 23°C which may indicate the subordinate presence of hot water microhabitats in cooler waters.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141096471","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":"In vivo measurement of strain in the periodontal space of pig (Sus scrofa) incisors using in-fiber Bragg sensors","authors":"Tracy E. Popowics,&nbsp;Isabelle Hwang,&nbsp;Jason Lu,&nbsp;Tammy Nguyen,&nbsp;Morgan Sample,&nbsp;Anissa Sangster,&nbsp;Derrick Tang,&nbsp;Christopher R. Dennison,&nbsp;Dan L. Romanyk,&nbsp;Katherine Rafferty,&nbsp;Geoffrey Greenlee","doi":"10.1002/jmor.21738","DOIUrl":"10.1002/jmor.21738","url":null,"abstract":"<p>The incisor teeth in pigs, <i>Sus scrofa</i>, function in association with a disc-shaped snout to explore the environment for potential food. Understanding how mechanical loading applied to the tooth deforms the periodontal ligament (PDL) is important to determining the role of periodontal mechanoreceptors during food exploration and feeding. The objective of this study was to use fiber Bragg (FBG) sensors to measure strain in vivo within the PDL space of pig incisors. The central mandibular incisors of pigs underwent spring loaded lingual tipping during FBG strain recording within the labial periodontal space. FBG sensors were placed within the periodontal space of the central mandibular incisors of ~2–3-month-old farm pigs. The magnitude and orientation of spring loads are expected to mimic incisor contact with food. During incisor tipping with load calibrated springs, FBG strains in vitro (<i>N</i> = 6) and in vivo (<i>N</i> = 6) recorded at comparable load levels overlapped in range (−10–20 με). Linear regressions between peak FBG strains, that is, the highest recorded strain value, and baseline strains, that is, strain without applied spring load, were significant across all in vivo experiments (peak strain at 200 g vs. baseline, <i>p</i> = .04; peak strain at 2000 g vs. baseline <i>p</i> = .03; peak strain at 2000 g vs. 200 g, <i>p</i> = .004). These linear relationships indicate that on a per experiment basis, the maximum measured strain at different spring loads showed predictable differences. A Friedman test of the absolute value of peak strain confirmed the significant increase in strain between baseline, 200 g, and 2000 g spring activation (<i>p</i> = .02). Mainly compressive strains were recorded in the labial PDL space and increases in spring load applied in vivo generated increases in FBG strain measurements. These results demonstrate the capacity for FBG sensors to be used in vivo to assess transmission of occlusal loads through the periodontium. PDL strain is associated with mechanoreceptor stimulation and is expected to affect the functional morphology of the incisors. The overall low levels of strain observed may correspond with the robust functional morphology of pig incisors and the tendency for pigs to encounter diverse foods and substrates during food exploration.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141087756","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":"Paleoneurology of stem palaeognaths clarifies the plesiomorphic condition of the crown bird central nervous system","authors":"Klara E. Widrig,&nbsp;Guillermo Navalón,&nbsp;Daniel J. Field","doi":"10.1002/jmor.21710","DOIUrl":"10.1002/jmor.21710","url":null,"abstract":"<p>Lithornithidae, an assemblage of volant Palaeogene fossil birds, provide our clearest insights into the early evolutionary history of Palaeognathae, the clade that today includes the flightless ratites and volant tinamous. The neotype specimen of <i>Lithornis vulturinus</i>, from the early Eocene (approximately 53 million years ago) of Europe, includes a partial neurocranium that has never been thoroughly investigated. Here, we describe these cranial remains including the nearly complete digital endocasts of the brain and bony labyrinth. The telencephalon of <i>Lithornis</i> is expanded and its optic lobes are ventrally shifted, as is typical for crown birds. The foramen magnum is positioned caudally, rather than flexed ventrally as in some crown birds, with the optic lobes, cerebellum, and foramen magnum shifted further ventrally. The overall brain shape is similar to that of tinamous, the only extant clade of flying palaeognaths, suggesting that several aspects of tinamou neuroanatomy may have been evolutionarily conserved since at least the early Cenozoic. The estimated ratio of the optic lobe's surface area relative to the total brain suggests a diurnal ecology. <i>Lithornis</i> may provide the clearest insights to date into the neuroanatomy of the ancestral crown bird, combining an ancestrally unflexed brain with a caudally oriented connection with the spinal cord, a moderately enlarged telencephalon, and ventrally shifted, enlarged optic lobes.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jmor.21710","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140957935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative morphology of male genitalia in antlions (Insecta, Neuroptera, Myrmeleontidae), with emphasis on owlflies (Ascalaphinae) and a possible structural evolutionary scenario","authors":"Yesenia Marquez-López,&nbsp;Caleb C. Martins,&nbsp;Luis M. Guevara-Chumacero,&nbsp;Andrés Ramírez-Ponce,&nbsp;Atilano Contreras-Ramos","doi":"10.1002/jmor.21701","DOIUrl":"10.1002/jmor.21701","url":null,"abstract":"<p>Male genitalia morphology in Myrmeleontidae has traditionally been insufficiently studied, although it has received increased attention for its diagnostic value in recent times. A neutral terminology has generally been applied in standard taxonomic practice, yet knowledge of an equivalent and stable terminology across taxa based on comparative morphology has been missing. Herein a detailed comparative morphology study with examples from most tribes within Myrmeleontidae, including owlflies (Ascalaphinae), attempts to relate external and internal genital structures based on a proposed groundplan for Neuroptera and Myrmeleontidae. We contend that a groundplan based on 10 abdominal segments, plus vestigial structures from an 11th segment, coherently depicts structural components across myrmeleontid taxa. A gonarcus, an element of Neuropterida amply referred in Neuroptera, is supported to represent the pair of abdominal appendages of segment X medially fused, with gonocoxite and gonostylus components. In most myrmeleontid taxa, basal (gonocoxites) and distal (gonostyli) components separate, with gonostyli positioned posteriorly with respect to gonocoxites, still united with translucent, lightly sclerotized tissue, forming a more or less conical structure, a proposed synapomorphy for the family. Ninth gonostyli are generally reduced (pulvini) and have migrated close to the base of gonarcus (10th gonocoxites). A pelta, also a potential synapomorphy for Myrmeleontidae, derives from paired setose surfaces of the 10th gonostyli, medially positioned (still evident in <i>Bubopsis</i>). Three structural types of gonarcus are diagnosed for illustrative purposes, as they may represent convergent constructs.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jmor.21701","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140912496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How to do functional morphology, take 2 or 50 years later","authors":"Susan W. Herring","doi":"10.1002/jmor.21709","DOIUrl":"https://doi.org/10.1002/jmor.21709","url":null,"abstract":"","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140907120","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":"Finite element analysis of kangaroo astragali: A new angle on the ankle","authors":"Peter J. Murphy,&nbsp;Andre J. Rowe,&nbsp;Emily J. Rayfield,&nbsp;Christine M. Janis","doi":"10.1002/jmor.21707","DOIUrl":"10.1002/jmor.21707","url":null,"abstract":"<p>Using finite element analysis on the astragali of five macropodine kangaroos (extant and extinct hoppers) and three sthenurine kangaroos (extinct proposed bipedal striders) we investigate how the stresses experienced by the ankle in similarly sized kangaroos of different hypothesized/known locomotor strategy compare under different simulation scenarios, intended to represent the moment of midstance at different gaits. These tests showed a clear difference between the performance of sthenurines and macropodines with the former group experiencing lower stress in simulated bipedal strides in all species compared with hopping simulations, supporting the hypothesis that sthenurines may have utilized this gait. The Pleistocene macropodine <i>Protemnodon</i> also performed differently from all other species studied, showing high stresses in all simulations except for bounding. This may support the hypothesis of <i>Protemnodon</i> being a quadrupedal bounder.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jmor.21707","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140891978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}