Variations in cochlea shape reveal different evolutionary adaptations in primates and rodents
Abstract The presence of a coiled cochlea is a unique feature of the therian inner ear. While some aspects of the cochlea are already known to affect hearing capacities, the full extent of the relationships between the morphology and function of this organ are not yet understood—especially when the...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2023-02-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-023-29478-z |
| _version_ | 1828035258875904000 |
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| author | Joaquin del Rio Roxana Taszus Manuela Nowotny Alexander Stoessel |
| author_facet | Joaquin del Rio Roxana Taszus Manuela Nowotny Alexander Stoessel |
| author_sort | Joaquin del Rio |
| collection | DOAJ |
| description | Abstract The presence of a coiled cochlea is a unique feature of the therian inner ear. While some aspects of the cochlea are already known to affect hearing capacities, the full extent of the relationships between the morphology and function of this organ are not yet understood—especially when the effect of body size differences between species is minimized. Here, focusing on Euarchontoglires, we explore cochlear morphology of 33 species of therian mammals with a restricted body size range. Using μCT scans, 3D models and 3D geometric morphometrics, we obtained shape information of the cochlea and used it to build phylogenetically corrected least square models with 12 hearing variables obtained from the literature. Our results reveal that different taxonomic groups differ significantly in cochlea shape. We further show that these shape differences are related to differences in hearing capacities between these groups, despite of similar cochlear lengths. Most strikingly, rodents with good low-frequency hearing display “tower-shaped” cochleae, achieved by increasing the degree of coiling of their cochlea. In contrast, primates present relatively wider cochleae and relative better high frequency hearing. These results suggest that primates and rodents increased their cochlea lengths through different morpho-evolutionary trajectories. |
| first_indexed | 2024-04-10T15:45:22Z |
| format | Article |
| id | doaj.art-7335878104c44d34bb6ccaa14e629fc9 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-04-10T15:45:22Z |
| publishDate | 2023-02-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-7335878104c44d34bb6ccaa14e629fc92023-02-12T12:09:02ZengNature PortfolioScientific Reports2045-23222023-02-0113111510.1038/s41598-023-29478-zVariations in cochlea shape reveal different evolutionary adaptations in primates and rodentsJoaquin del Rio0Roxana Taszus1Manuela Nowotny2Alexander Stoessel3Department of Archaeogenetics, Max Planck Institute for Evolutionary AnthropologyInstitute of Zoology and Evolutionary Research, Friedrich-Schiller-University JenaInstitute of Zoology and Evolutionary Research, Friedrich-Schiller-University JenaDepartment of Archaeogenetics, Max Planck Institute for Evolutionary AnthropologyAbstract The presence of a coiled cochlea is a unique feature of the therian inner ear. While some aspects of the cochlea are already known to affect hearing capacities, the full extent of the relationships between the morphology and function of this organ are not yet understood—especially when the effect of body size differences between species is minimized. Here, focusing on Euarchontoglires, we explore cochlear morphology of 33 species of therian mammals with a restricted body size range. Using μCT scans, 3D models and 3D geometric morphometrics, we obtained shape information of the cochlea and used it to build phylogenetically corrected least square models with 12 hearing variables obtained from the literature. Our results reveal that different taxonomic groups differ significantly in cochlea shape. We further show that these shape differences are related to differences in hearing capacities between these groups, despite of similar cochlear lengths. Most strikingly, rodents with good low-frequency hearing display “tower-shaped” cochleae, achieved by increasing the degree of coiling of their cochlea. In contrast, primates present relatively wider cochleae and relative better high frequency hearing. These results suggest that primates and rodents increased their cochlea lengths through different morpho-evolutionary trajectories.https://doi.org/10.1038/s41598-023-29478-z |
| spellingShingle | Joaquin del Rio Roxana Taszus Manuela Nowotny Alexander Stoessel Variations in cochlea shape reveal different evolutionary adaptations in primates and rodents Scientific Reports |
| title | Variations in cochlea shape reveal different evolutionary adaptations in primates and rodents |
| title_full | Variations in cochlea shape reveal different evolutionary adaptations in primates and rodents |
| title_fullStr | Variations in cochlea shape reveal different evolutionary adaptations in primates and rodents |
| title_full_unstemmed | Variations in cochlea shape reveal different evolutionary adaptations in primates and rodents |
| title_short | Variations in cochlea shape reveal different evolutionary adaptations in primates and rodents |
| title_sort | variations in cochlea shape reveal different evolutionary adaptations in primates and rodents |
| url | https://doi.org/10.1038/s41598-023-29478-z |
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