1
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Fritzsch B, Schultze HP, Elliott KL. The evolution of the various structures required for hearing in Latimeria and tetrapods. IBRO Neurosci Rep 2023; 14:325-341. [PMID: 37006720 PMCID: PMC10063410 DOI: 10.1016/j.ibneur.2023.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Sarcopterygians evolved around 415 Ma and have developed a unique set of features, including the basilar papilla and the cochlear aqueduct of the inner ear. We provide an overview that shows the morphological integration of the various parts needed for hearing, e.g., basilar papilla, tectorial membrane, cochlear aqueduct, lungs, and tympanic membranes. The lagena of the inner ear evolved from a common macula of the saccule several times. It is near this lagena where the basilar papilla forms in Latimeria and tetrapods. The basilar papilla is lost in lungfish, certain caecilians and salamanders, but is transformed into the cochlea of mammals. Hearing in bony fish and tetrapods involves particle motion to improve sound pressure reception within the ear but also works without air. Lungs evolved after the chondrichthyans diverged and are present in sarcopterygians and actinopterygians. Lungs open to the outside in tetraposomorph sarcopterygians but are transformed from a lung into a swim bladder in ray-finned fishes. Elasmobranchs, polypterids, and many fossil fishes have open spiracles. In Latimeria, most frogs, and all amniotes, a tympanic membrane covering the spiracle evolved independently. The tympanic membrane is displaced by pressure changes and enabled tetrapods to perceive airborne sound pressure waves. The hyomandibular bone is associated with the spiracle/tympanic membrane in actinopterygians and piscine sarcopterygians. In tetrapods, it transforms into the stapes that connects the oval window of the inner ear with the tympanic membrane and allows hearing at higher frequencies by providing an impedance matching and amplification mechanism. The three characters-basilar papilla, cochlear aqueduct, and tympanic membrane-are fluid related elements in sarcopterygians, which interact with a set of unique features in Latimeria. Finally, we explore the possible interaction between the unique intracranial joint, basicranial muscle, and an enlarged notochord that allows fluid flow to the foramen magnum and the cochlear aqueduct which houses a comparatively small brain.
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Affiliation(s)
- Bernd Fritzsch
- Department of Biology & Department of Otolaryngology, University of Iowa, IA, USA
- Correspondence to: Department of Biology & Department of Otolaryngology, University of Iowa, Iowa City, IA, 52242, USA.
| | | | - Karen L. Elliott
- Department of Biology & Department of Otolaryngology, University of Iowa, IA, USA
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2
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Lipovsek M, Elgoyhen AB. The evolutionary tuning of hearing. Trends Neurosci 2023; 46:110-123. [PMID: 36621369 DOI: 10.1016/j.tins.2022.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/29/2022] [Accepted: 12/06/2022] [Indexed: 01/08/2023]
Abstract
After the transition to life on land, tympanic middle ears emerged separately in different groups of tetrapods, facilitating the efficient detection of airborne sounds and paving the way for high frequency sensitivity. The processes that brought about high-frequency hearing in mammals are tightly linked to the accumulation of coding sequence changes in inner ear genes; many of which were selected during evolution. These include proteins involved in hair bundle morphology, mechanotransduction and high endolymphatic potential, somatic electromotility for sound amplification, ribbon synapses for high-fidelity transmission of sound stimuli, and efferent synapses for the modulation of sound amplification. Here, we review the molecular evolutionary processes behind auditory functional innovation. Overall, the evidence to date supports the hypothesis that changes in inner ear proteins were central to the fine tuning of mammalian hearing.
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Affiliation(s)
- Marcela Lipovsek
- Ear Institute, Faculty of Brain Sciences, University College London, London, UK.
| | - Ana Belén Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres" (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
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3
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Wang HB, Hoffmann S, Wang DC, Wang YQ. A new mammal from the Lower Cretaceous Jehol Biota and implications for eutherian evolution. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210042. [PMID: 35125007 PMCID: PMC8819371 DOI: 10.1098/rstb.2021.0042] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Here we report on a new Early Cretaceous eutherian represented by a partial skeleton from the Jiufotang Formation at Sihedang site, Lingyuan City, Liaoning Province that fills a crucial gap between the earliest eutherians from the Yixian Formation and later Cretaceous eutherians. The new specimen reveals, to our knowledge for the first time in eutherians, that the Meckelian cartilage was ossified but reduced in size, confirming a complete detachment of the middle ear from the lower jaw. Seven hyoid elements, including paired stylohyals, epihyals and thyrohyals and the single basihyal are preserved. For the inner ear the ossified primary lamina, base of the secondary lamina, ossified cochlear ganglion and secondary crus commune are present and the cochlear canal is coiled through 360°. In addition, plesiomorphic features of the dentition include weak conules, lack of pre- and post-cingula and less expanded protocones on the upper molars and height differential between the trigonid and talonid, a large protoconid and a small paraconid on the lower molars. The new taxon displays an alternating pattern of tooth replacement with P3 being the last upper premolar to erupt similar to the basal eutherian Juramaia. Parsimony analysis places the new taxon with Montanalestes, Sinodelphys and Ambolestes as a sister group to other eutherians. This article is part of the theme issue 'The impact of Chinese palaeontology on evolutionary research'.
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Affiliation(s)
- Hai-Bing Wang
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, People's Republic of China.,Centre for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Beijing, People's Republic of China.,Key State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, People's Republic of China
| | - Simone Hoffmann
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY, USA
| | - Dian-Can Wang
- Department of Oral and Maxillofacial Surgery, Peking University School of Stomatology, 22 South Zhongguancun Avenue, Beijing, People's Republic of China
| | - Yuan-Qing Wang
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, People's Republic of China.,Centre for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Beijing, People's Republic of China.,College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
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4
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Krause DW, Hoffmann S, Lyson TR, Dougan LG, Petermann H, Tecza A, Chester SGB, Miller IM. New Skull Material of Taeniolabis taoensis (Multituberculata, Taeniolabididae) from the Early Paleocene (Danian) of the Denver Basin, Colorado. J MAMM EVOL 2021; 28:1083-1143. [PMID: 34924738 PMCID: PMC8667543 DOI: 10.1007/s10914-021-09584-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2021] [Indexed: 11/26/2022]
Abstract
Taeniolabis taoensis is an iconic multituberculate mammal of early Paleocene (Puercan 3) age from the Western Interior of North America. Here we report the discovery of significant new skull material (one nearly complete cranium, two partial crania, one nearly complete dentary) of T. taoensis in phosphatic concretions from the Corral Bluffs study area, Denver Formation (Danian portion), Denver Basin, Colorado. The new skull material provides the first record of the species from the Denver Basin, where the lowest in situ specimen occurs in river channel deposits ~730,000 years after the Cretaceous-Paleogene boundary, roughly coincident with the first appearance of legumes in the basin. The new material, in combination with several previously described and undescribed specimens from the Nacimiento Formation of the San Juan Basin, New Mexico, is the subject of detailed anatomical study, aided by micro-computed tomography. Our analyses reveal many previously unknown aspects of skull anatomy. Several regions (e.g., anterior portions of premaxilla, orbit, cranial roof, occiput) preserved in the Corral Bluffs specimens allow considerable revision of previous reconstructions of the external cranial morphology of T. taoensis. Similarly, anatomical details of the ascending process of the dentary are altered in light of the new material. Although details of internal cranial anatomy (e.g., nasal and endocranial cavities) are difficult to discern in the available specimens, we provide, based on UCMP 98083 and DMNH.EPV 95284, the best evidence to date for inner ear structure in a taeniolabidoid multituberculate. The cochlear canal of T. taoensis is elongate and gently curved and the vestibule is enlarged, although to a lesser degree than in Lambdopsalis.
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Affiliation(s)
- David W. Krause
- Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205 USA
- Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794-8081 USA
| | - Simone Hoffmann
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568 USA
| | - Tyler R. Lyson
- Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205 USA
| | - Lindsay G. Dougan
- Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205 USA
| | - Holger Petermann
- Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205 USA
| | - Adrienne Tecza
- Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205 USA
| | - Stephen G. B. Chester
- Department of Anthropology, Brooklyn College, City University of New York, 2900 Bedford Avenue, Brooklyn, NY 11210 USA
- Department of Anthropology, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016 USA
- New York Consortium in Evolutionary Primatology, 200 Central Park West, New York, NY 10024 USA
| | - Ian M. Miller
- Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205 USA
- National Geographic Society, 1145 17th Street NW, Washington, DC 20036 USA
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5
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Jurassic mammaliaform petrosals from Western Siberia (Russia) and implications for early mammalian inner-ear anatomy. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlab096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Five partially preserved mammaliaform petrosals recovered from Middle Jurassic sediments of the Berezovsk coal mine (Krasnoyarsk Krai, Russia) show similarities to other early mammaliaforms like the morganucodontan Morganucodon and the docodontan Haldanodon in having an inflated promontorium and a curved and apically inflated cochlear canal, but they are distinct from dryolestoid and derived mammalian petrosals by the weak coiling of the cochlear duct and the presence of a perilymphatic foramen with an open perilymphatic sulcus. The two larger and robust specimens exhibit striking similarities to docodontan petrosals. Inside the bone an intricate circumpromontorial venous plexus was discovered, as recently described for the docodontan Borealestes, confirming that this structure is consistently present in basal non-mammalian mammaliaforms. The three smaller and slender petrosals probably belong to haramiyidans and are unique in showing a septum-like structure medially along the cochlear nerve entrance. The protruding perforated bony bar, which is preserved in two of the three, is interpreted here to be a remnant of a bony septum with multiple foramina for cochlear nerve fibres, representing an autapomorphic feature of Haramiyida. This newly described passageway for nerve fibres shows that the formation of the osteological structure surrounding the nervous pathways of the cochlea is more plastic among the non-mammalian mammaliaforms than previously thought.
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6
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New Specimens of Reigitherium bunodontum from the Late Cretaceous La Colonia Formation, Patagonia, Argentina and Meridiolestidan Diversity in South America. J MAMM EVOL 2021. [DOI: 10.1007/s10914-021-09585-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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7
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Mammalian Petrosals from the Upper Jurassic Morrison Formation (Utah, USA) Reveal Non-canonical Evolution of Middle and Inner Ear Characters. J MAMM EVOL 2021. [DOI: 10.1007/s10914-021-09586-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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8
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Shelley SL, Bertrand OC, Brusatte SL, Williamson TE. Petrosal Anatomy of the Paleocene Eutherian Mammal Deltatherium fundaminis (Cope, 1881). J MAMM EVOL 2021; 28:1161-1180. [PMID: 34483638 PMCID: PMC8406390 DOI: 10.1007/s10914-021-09568-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2021] [Indexed: 12/04/2022]
Abstract
We describe the tympanic anatomy of the petrosal of Deltatherium fundaminis, an enigmatic Paleocene mammal based on cranial specimens recovered from New Mexico, U.S.A. Although the ear region of Deltatherium has previously been described, there has not been a comprehensive, well-illustrated contribution using current anatomical terminology. The dental and cranial anatomy of Deltatherium is a chimera, with morphological similarities to both ‘condylarth’ and ‘cimolestan’ taxa. As such, the phylogenetic relationships of this taxon have remained elusive since its discovery, and it has variably been associated with Arctocyonidae, Pantodonta and Tillodontia. The petrosal of Deltatherium is anteriorly bordered by an open space comprising a contiguous carotid opening and pyriform fenestra. The promontorium features both a small rostral tympanic process and small epitympanic wing but lacks well-marked sulci. A large ventral facing external aperture of the canaliculus cochleae is present and bordered posteriorly by a well-developed caudal tympanic process. The hiatus Fallopii opens on the ventral surface of the petrosal. The tegmen tympani is mediolaterally broad and anteriorly expanded, and its anterior margin is perforated by a foramen for the ramus superior of the stapedial artery. The tympanohyal is small but approximates the caudal tympanic process to nearly enclose the stylomastoid notch. The mastoid is widely exposed on the basicranium and bears an enlarged mastoid process, separate from the paraoccipital process. These new observations provide novel anatomical data corroborating previous hypotheses regarding the plesiomorphic eutherian condition but also reveal subtle differences among Paleocene eutherians that have the potential to help inform the phylogeny of Deltatherium.
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Affiliation(s)
- Sarah L Shelley
- School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom.,Carnegie Museum of Natural History, Pittsburgh, Pennsylvania United States of America
| | - Ornella C Bertrand
- School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Stephen L Brusatte
- School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom.,New Mexico Museum of Natural History and Science, Albuquerque, New Mexico United States of America
| | - Thomas E Williamson
- New Mexico Museum of Natural History and Science, Albuquerque, New Mexico United States of America
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9
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Grossnickle DM, Weaver LN, Jäger KRK, Schultz JA. The evolution of anteriorly directed molar occlusion in mammals. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlab039] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Abstract
In non-mammalian synapsids and early mammals, evolutionary transformations in the feeding and hearing apparatuses are posited to have been prerequisites for the radiation of extant mammals. Unlike most vertebrates, including many early synapsids, mammals have precise dental occlusion, a lower jaw composed of one bone, and middle ear ossicles derived from ancestral jaw bones. We illuminate a related functional transition: therian mammals (eutherians and metatherians) evolved anteriorly directed chewing strokes, which are absent in other synapsid lineages. Anteriorly directed jaw movement during occlusion necessitates anteriorly directed muscle force vectors, and we posit that a shift in muscle orientation is reflected in the fossil record by the evolutionary appearance of a posteriorly positioned angular process in cladotherians (therians and their close kin). Anteriorly directed occlusion might have been absent in earlier synapsids because of the presence of attached middle ear elements in the posterior region of the jaw that prohibited the posterior insertion of jaw musculature. These changes to the masticatory apparatus in cladotherians are likely to have permitted the evolution of novel masticatory movements, including grinding in both the anterior and medial directions (e.g. rodents and ungulates, respectively). Thus, this evolutionary transition might have been a crucial prerequisite for the dietary diversification of therians.
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Affiliation(s)
- David M Grossnickle
- Department of Biology, Life Sciences Building, University of Washington, Seattle, WA, USA
| | - Lucas N Weaver
- Department of Biology, Life Sciences Building, University of Washington, Seattle, WA, USA
| | - Kai R K Jäger
- Section Palaeontology, Institute of Geosciences, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 8, Bonn, Germany
| | - Julia A Schultz
- Section Palaeontology, Institute of Geosciences, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 8, Bonn, Germany
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10
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MacPhee R, Del Pino SH, Kramarz A, Forasiepi AM, Bond M, Sulser RB. Cranial Morphology and Phylogenetic Relationships of Trigonostylops wortmani, an Eocene South American Native Ungulate. BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY 2021. [DOI: 10.1206/0003-0090.449.1.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- R.D.E. MacPhee
- Department of Mammalogy/Vertebrate Zoology and Richard Gilder Graduate School, American Museum of Natural History
| | | | - Alejandro Kramarz
- Sección Paleontología de Vertebrados, Museo Argentino de Ciencias Naturales Bernardino Rivadavia, CONICET, Buenos Aires, Argentina
| | | | - Mariano Bond
- Departamento Científico de Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina
| | - R. Benjamin Sulser
- Department of Mammalogy/Vertebrate Zoology and Richard Gilder Graduate School, American Museum of Natural History
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11
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Wang J, Wible JR, Guo B, Shelley SL, Hu H, Bi S. A monotreme-like auditory apparatus in a Middle Jurassic haramiyidan. Nature 2021; 590:279-283. [PMID: 33505017 DOI: 10.1038/s41586-020-03137-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 12/10/2020] [Indexed: 01/30/2023]
Abstract
Among extant vertebrates, mammals are distinguished by having a chain of three auditory ossicles (the malleus, incus and stapes) that transduce sound waves and promote an increased range of audible-especially high-frequencies1. By contrast, the homologous bones in early fossil mammals and relatives also functioned in chewing through their bony attachments to the lower jaw2. Recent discoveries of well-preserved Mesozoic mammals have provided glimpses into the transition from the dual (masticatory and auditory) to the single auditory function for the ossicles, which is now widely accepted to have occurred at least three times in mammal evolution3-6. Here we report a skull and postcranium that we refer to the haramiyidan Vilevolodon diplomylos (dating to the Middle Jurassic epoch (160 million years ago)) and that shows excellent preservation of the malleus, incus and ectotympanic (which supports the tympanic membrane). After comparing this fossil with other Mesozoic and extant mammals, we propose that the overlapping incudomallear articulation found in this and other Mesozoic fossils, in extant monotremes and in early ontogeny in extant marsupials and placentals is a morphology that evolved in several groups of mammals in the transition from the dual to the single function for the ossicles.
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Affiliation(s)
- Junyou Wang
- Centre for Vertebrate Evolutionary Biology, Institute of Palaeontology, Yunnan University, Kunming, China.,Inner Mongolia Museum of Natural History, Hohhot, China
| | - John R Wible
- Centre for Vertebrate Evolutionary Biology, Institute of Palaeontology, Yunnan University, Kunming, China. .,Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, PA, USA.
| | - Bin Guo
- Inner Mongolia Museum of Natural History, Hohhot, China
| | - Sarah L Shelley
- Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, PA, USA.,School of Geosciences, University of Edinburgh, Edinburgh, UK
| | - Han Hu
- Zoology Division, School of Environmental and Rural Sciences, University of New England, Armidale, New South Wales, Australia
| | - Shundong Bi
- Centre for Vertebrate Evolutionary Biology, Institute of Palaeontology, Yunnan University, Kunming, China. .,Department of Biology, Indiana University of Pennsylvania, Indiana, PA, USA.
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12
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Panciroli E, Benson RBJ, Fernandez V, Butler RJ, Fraser NC, Luo ZX, Walsh S. New species of mammaliaform and the cranium of Borealestes (Mammaliformes: Docodonta) from the Middle Jurassic of the British Isles. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlaa144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Abstract
Docodonta are one of the earliest diverging groups of mammaliaforms, and their morphology provides key information on the transition between non-mammalian cynodonts and Mammalia. We describe the partial skulls of two docodontans Borealestes serendipitus and Borealestes cuillinensis sp. nov. from the Kilmaluag Formation (Middle Jurassic: Bathonian), Isle of Skye, Scotland. We visualize their cranial anatomy using laboratory and synchrotron X-ray micro-CT. The skulls belong to two partial skeletons, currently comprising the most complete Mesozoic mammal fossils reported from the British Isles. The associated upper and lower dentitions show that the lower dentition of Borealestes is not diagnostic to species level. We establish, B. cuillinensis, based on upper molar characters, and re-identify upper molars previously assigned to ‘Borealestes’ mussettae as belonging to B. cuillinensis. ‘Borealestes’ mussettae, based on distinctive lower molars, is found to be morphologically and phylogenetically distinct from Borealestes, necessitating assignment to a new genus, Dobunnodon gen. nov. The skulls of Borealestes retain many plesiomorphic features seen in Morganucodon but absent in more crownward mammaliaforms. Our study highlights that generic and species taxonomy of docodontans are more reliable when based on both upper and lower teeth, while lower molar morphology may underrepresent the true diversity of Mesozoic mammaliaforms.
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Affiliation(s)
- Elsa Panciroli
- Natural Science Department, National Museums Scotland, Edinburgh, Scotland, UK
- School of Geosciences, Grant Institute, University of Edinburgh, Scotland, UK
- Department of Earth Sciences, University of Oxford, Oxford, England, UK
| | - Roger B J Benson
- Department of Earth Sciences, University of Oxford, Oxford, England, UK
| | - Vincent Fernandez
- European Synchrotron Radiation Facility (ESRF), Beamline, Grenoble, France
- Natural History Museum, London, UK
| | - Richard J Butler
- School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Nicholas C Fraser
- Natural Science Department, National Museums Scotland, Edinburgh, Scotland, UK
- School of Geosciences, Grant Institute, University of Edinburgh, Scotland, UK
| | - Zhe-Xi Luo
- Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois, USA
| | - Stig Walsh
- Natural Science Department, National Museums Scotland, Edinburgh, Scotland, UK
- School of Geosciences, Grant Institute, University of Edinburgh, Scotland, UK
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13
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Honkura Y, Hayashi S, Abe H, Murakami G, Rodríguez-Vázquez JF, Shibata S. The third vascular route of the inner ear or the canal of Cotugno: Its topographical anatomy, fetal development, and contribution to ossification of the otic capsule cartilage. Anat Rec (Hoboken) 2020; 304:872-882. [PMID: 32865892 DOI: 10.1002/ar.24508] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/03/2020] [Accepted: 06/29/2020] [Indexed: 01/03/2023]
Abstract
Three vascular routes to the inner ear are known: (a) through the internal acoustic meatus with the vestibulocochlear nerve; (b) from the endolymphatic duct aperture; and (c) along the canal of Cotugno (CC) inserted into the vestibular part of the ear from the superior or brain side. The third is believed to contain only veins. Examinations of 33 human embryos and fetuses at 6-40 weeks demonstrated that (a) the CC appeared as a recess of epidural mesenchymal tissues at the superior aspect of the otic capsule cartilage in embryos and it was inserted deeply to issue multiple peripheral divisions inferolaterally and posteriorly at midterm; (b) the CC consistently passed through a ring of the superior or anterior semicircular canal and contained both, the arteries from the vestibulocochlear nerve origin at the midbrain and the vein draining into the sigmoid sinus or petrosal sinuses; and (c) the CC appeared not to contribute to ossification of the otic capsule cartilage but, after endochondral ossification of the internal ear, woven bone development occurred along a smooth interface of the CC with the ossified ear. In contrast, another interface between the developing bone and the residual cartilage of the otic capsule was rough and wavy with many short bony columns, called osseous globules. In addition, the endolymphatic duct accompanied veins but no arteries. Our results show that the CC is a major vascular route to the vestibular part of the otic capsule cartilage, but its role appears to be limited after ossification.
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Affiliation(s)
- Yohei Honkura
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Shogo Hayashi
- Department of Anatomy, School of Medicine, International University of Health and Welfare, Narita, Japan
| | - Hiroshi Abe
- Department of Anatomy, Akita University School of Medicine, Akita, Japan
| | - Gen Murakami
- Division of Internal Medicine, Jikou-kai Clinic of Home visits, Sapporo, Japan
| | | | - Shunichi Shibata
- Department of Maxillofacial Anatomy, Graduate School of Tokyo Medical and Dental University, Tokyo, Japan
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14
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Mao F, Hu Y, Li C, Wang Y, Chase MH, Smith AK, Meng J. Integrated hearing and chewing modules decoupled in a Cretaceous stem therian mammal. Science 2019; 367:305-308. [PMID: 31806694 DOI: 10.1126/science.aay9220] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 11/21/2019] [Indexed: 12/13/2022]
Abstract
On the basis of multiple skeletal specimens from Liaoning, China, we report a new genus and species of Cretaceous stem therian mammal that displays decoupling of hearing and chewing apparatuses and functions. The auditory bones, including the surangular, have no bone contact with the ossified Meckel's cartilage; the latter is loosely lodged on the medial rear of the dentary. This configuration probably represents the initial morphological stage of the definitive mammalian middle ear. Evidence shows that hearing and chewing apparatuses have evolved in a modular fashion. Starting as an integrated complex in non-mammaliaform cynodonts, the two modules, regulated by similar developmental and genetic mechanisms, eventually decoupled during the evolution of mammals, allowing further improvement for more efficient hearing and mastication.
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Affiliation(s)
- Fangyuan Mao
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China. .,CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China.,Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA
| | - Yaoming Hu
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China
| | - Chuankui Li
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China.,CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China
| | - Yuanqing Wang
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China.,CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China
| | - Morgan Hill Chase
- Microscopy and Imaging Facility, American Museum of Natural History, New York, NY 10024, USA
| | - Andrew K Smith
- Microscopy and Imaging Facility, American Museum of Natural History, New York, NY 10024, USA
| | - Jin Meng
- Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA. .,Earth and Environmental Sciences, Graduate Center, City University of New York, New York, NY 10016, USA
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