Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta)
Abstract Insect feeding structures, such as mandibles, interact with the ingesta (food or/and substrate) and can be adapted in morphology, composition of material and mechanical properties. The foraging on abrasive ingesta, as on algae covering rocks, is particularly challenging because the mandible...
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| Language: | English |
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Nature Portfolio
2024-02-01
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| Series: | Scientific Reports |
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| Online Access: | https://doi.org/10.1038/s41598-024-55211-5 |
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| author | Wencke Krings Patrick Below Stanislav N. Gorb |
| author_facet | Wencke Krings Patrick Below Stanislav N. Gorb |
| author_sort | Wencke Krings |
| collection | DOAJ |
| description | Abstract Insect feeding structures, such as mandibles, interact with the ingesta (food or/and substrate) and can be adapted in morphology, composition of material and mechanical properties. The foraging on abrasive ingesta, as on algae covering rocks, is particularly challenging because the mandibles will be prone to wear and structural failure, thus suggesting the presence of mandibular adaptations to accompany this feeding behavior. Adaptations to this are well studied in the mouthparts of molluscs and sea urchins, but for insects there are large gaps in our knowledge. In this study, we investigated the mandibles of a grazing insect, the larvae of the trichopteran Glossosoma boltoni. Using scanning electron microscopy, wear was documented on the mandibles. The highest degree was identified on the medial surface of the sharp mandible tip. Using nanoindentation, the mechanical properties, such as hardness and Young’s modulus, of the medial and lateral mandible cuticles were tested. We found, that the medial cuticle of the tip was significantly softer and more flexible than the lateral one. These findings indicate that a self-sharpening mechanism is present in the mandibles of this species, since the softer medial cuticle is probably abraded faster than the harder lateral one, leading to sharp mandible tips. To investigate the origins of these properties, we visualized the degree of tanning by confocal laser scanning microscopy. The autofluorescence signal related to the mechanical property gradients. The presence of transition and alkaline earth metals by energy dispersive X-ray spectroscopy was also tested. We found Ca, Cl, Cu, Fe, K, Mg, Mn, P, S, Si, and Zn in the cuticle, but the content was very low and did not correlate with the mechanical property values. |
| first_indexed | 2024-03-07T15:01:58Z |
| format | Article |
| id | doaj.art-03de44d7020b474aa59ff9cfe1b3db68 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-03-07T15:01:58Z |
| publishDate | 2024-02-01 |
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| series | Scientific Reports |
| spelling | doaj.art-03de44d7020b474aa59ff9cfe1b3db682024-03-05T19:04:57ZengNature PortfolioScientific Reports2045-23222024-02-0114111610.1038/s41598-024-55211-5Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta)Wencke Krings0Patrick Below1Stanislav N. Gorb2Department of Electron Microscopy, Institute of Cell and Systems Biology of Animals, Universität HamburgDepartment of Electron Microscopy, Institute of Cell and Systems Biology of Animals, Universität HamburgDepartment of Functional Morphology and Biomechanics, Zoological Institute, Christian-Albrechts-Universität zu KielAbstract Insect feeding structures, such as mandibles, interact with the ingesta (food or/and substrate) and can be adapted in morphology, composition of material and mechanical properties. The foraging on abrasive ingesta, as on algae covering rocks, is particularly challenging because the mandibles will be prone to wear and structural failure, thus suggesting the presence of mandibular adaptations to accompany this feeding behavior. Adaptations to this are well studied in the mouthparts of molluscs and sea urchins, but for insects there are large gaps in our knowledge. In this study, we investigated the mandibles of a grazing insect, the larvae of the trichopteran Glossosoma boltoni. Using scanning electron microscopy, wear was documented on the mandibles. The highest degree was identified on the medial surface of the sharp mandible tip. Using nanoindentation, the mechanical properties, such as hardness and Young’s modulus, of the medial and lateral mandible cuticles were tested. We found, that the medial cuticle of the tip was significantly softer and more flexible than the lateral one. These findings indicate that a self-sharpening mechanism is present in the mandibles of this species, since the softer medial cuticle is probably abraded faster than the harder lateral one, leading to sharp mandible tips. To investigate the origins of these properties, we visualized the degree of tanning by confocal laser scanning microscopy. The autofluorescence signal related to the mechanical property gradients. The presence of transition and alkaline earth metals by energy dispersive X-ray spectroscopy was also tested. We found Ca, Cl, Cu, Fe, K, Mg, Mn, P, S, Si, and Zn in the cuticle, but the content was very low and did not correlate with the mechanical property values.https://doi.org/10.1038/s41598-024-55211-5CuticleElemental compositionMechanical propertiesFeedingWear |
| spellingShingle | Wencke Krings Patrick Below Stanislav N. Gorb Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta) Scientific Reports Cuticle Elemental composition Mechanical properties Feeding Wear |
| title | Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta) |
| title_full | Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta) |
| title_fullStr | Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta) |
| title_full_unstemmed | Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta) |
| title_short | Mandible mechanical properties and composition of the larval Glossosoma boltoni (Trichoptera, Insecta) |
| title_sort | mandible mechanical properties and composition of the larval glossosoma boltoni trichoptera insecta |
| topic | Cuticle Elemental composition Mechanical properties Feeding Wear |
| url | https://doi.org/10.1038/s41598-024-55211-5 |
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