Transient role of the middle ear as a lower jaw support across mammals
Mammals articulate their jaws using a novel joint between the dentary and squamosal bones. In eutherian mammals, this joint forms in the embryo, supporting feeding and vocalisation from birth. In contrast, marsupials and monotremes exhibit extreme altriciality and are born before the bones of the no...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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eLife Sciences Publications Ltd
2020-06-01
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| Series: | eLife |
| Subjects: | |
| Online Access: | https://elifesciences.org/articles/57860 |
| _version_ | 1811180967157563392 |
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| author | Neal Anthwal Jane C Fenelon Stephen D Johnston Marilyn B Renfree Abigail S Tucker |
| author_facet | Neal Anthwal Jane C Fenelon Stephen D Johnston Marilyn B Renfree Abigail S Tucker |
| author_sort | Neal Anthwal |
| collection | DOAJ |
| description | Mammals articulate their jaws using a novel joint between the dentary and squamosal bones. In eutherian mammals, this joint forms in the embryo, supporting feeding and vocalisation from birth. In contrast, marsupials and monotremes exhibit extreme altriciality and are born before the bones of the novel mammalian jaw joint form. These mammals need to rely on other mechanisms to allow them to feed. Here, we show that this vital function is carried out by the earlier developing, cartilaginous incus of the middle ear, abutting the cranial base to form a cranio-mandibular articulation. The nature of this articulation varies between monotremes and marsupials, with juvenile monotremes retaining a double articulation, similar to that of the fossil mammaliaform Morganucodon, while marsupials use a versican-rich matrix to stabilise the jaw against the cranial base. These findings provide novel insight into the evolution of mammals and the changing relationship between the jaw and ear. |
| first_indexed | 2024-04-11T09:12:06Z |
| format | Article |
| id | doaj.art-c8d03251beb14dacaa8778a690000edf |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-04-11T09:12:06Z |
| publishDate | 2020-06-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-c8d03251beb14dacaa8778a690000edf2022-12-22T04:32:29ZengeLife Sciences Publications LtdeLife2050-084X2020-06-01910.7554/eLife.57860Transient role of the middle ear as a lower jaw support across mammalsNeal Anthwal0https://orcid.org/0000-0002-4104-7839Jane C Fenelon1https://orcid.org/0000-0001-8771-5196Stephen D Johnston2Marilyn B Renfree3https://orcid.org/0000-0002-4589-0436Abigail S Tucker4https://orcid.org/0000-0001-8871-6094Centre for Craniofacial and Regenerative Biology, King's College London, London, United KingdomSchool of BioSciences, University of Melbourne, Victoria, AustraliaSchool of Agriculture and Food Sciences, University of Queensland, Gatton, AustraliaSchool of BioSciences, University of Melbourne, Victoria, AustraliaCentre for Craniofacial and Regenerative Biology, King's College London, London, United KingdomMammals articulate their jaws using a novel joint between the dentary and squamosal bones. In eutherian mammals, this joint forms in the embryo, supporting feeding and vocalisation from birth. In contrast, marsupials and monotremes exhibit extreme altriciality and are born before the bones of the novel mammalian jaw joint form. These mammals need to rely on other mechanisms to allow them to feed. Here, we show that this vital function is carried out by the earlier developing, cartilaginous incus of the middle ear, abutting the cranial base to form a cranio-mandibular articulation. The nature of this articulation varies between monotremes and marsupials, with juvenile monotremes retaining a double articulation, similar to that of the fossil mammaliaform Morganucodon, while marsupials use a versican-rich matrix to stabilise the jaw against the cranial base. These findings provide novel insight into the evolution of mammals and the changing relationship between the jaw and ear.https://elifesciences.org/articles/57860monotremesMarsupialsmammalsevolutionjaw jointmiddle ear |
| spellingShingle | Neal Anthwal Jane C Fenelon Stephen D Johnston Marilyn B Renfree Abigail S Tucker Transient role of the middle ear as a lower jaw support across mammals eLife monotremes Marsupials mammals evolution jaw joint middle ear |
| title | Transient role of the middle ear as a lower jaw support across mammals |
| title_full | Transient role of the middle ear as a lower jaw support across mammals |
| title_fullStr | Transient role of the middle ear as a lower jaw support across mammals |
| title_full_unstemmed | Transient role of the middle ear as a lower jaw support across mammals |
| title_short | Transient role of the middle ear as a lower jaw support across mammals |
| title_sort | transient role of the middle ear as a lower jaw support across mammals |
| topic | monotremes Marsupials mammals evolution jaw joint middle ear |
| url | https://elifesciences.org/articles/57860 |
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