1
|
Gilgenreiner M, Kurze C. Age dominates flight distance and duration, while body size shapes flight speed in Bombus terrestris L. (Hymenoptera: Apidae). Proc Biol Sci 2024; 291:20241001. [PMID: 39079662 PMCID: PMC11288671 DOI: 10.1098/rspb.2024.1001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 06/04/2024] [Accepted: 06/05/2024] [Indexed: 08/03/2024] Open
Abstract
Flight plays a crucial role in the fitness of insect pollinators, such as bumblebees. Despite their relatively large body size compared with their wings, bumblebees can fly under difficult ambient conditions, such as cooler temperatures. While their body size is often positively linked to their foraging range and flight ability, the influence of age remains less explored. Here, we studied the flight performance (distance, duration and speed) of ageing bumblebee workers using tethered flight mills. Additionally, we measured their intertegular distance and dry mass as proxies for their body size. We found that the flight distance and duration were predominantly influenced by age, challenging assumptions that age does not play a key role in foraging and task allocation. From the age of 7 to 14 days, flight distance and duration increased sixfold and fivefold, respectively. Conversely, the body size primarily impacted the maximum and average flight speed of workers. Our findings indicate that age substantially influences the flight distance and duration in bumblebee workers, affecting foraging performance and potentially altering task allocation strategies. This underscores the importance of considering individual age and physiological changes alongside body size/mass in experiments involving bumblebee workers.
Collapse
Affiliation(s)
- Milena Gilgenreiner
- Institute for Zoology and Evolutionary Biology, University of Regensburg, Regensburg, Germany
| | - Christoph Kurze
- Institute for Zoology and Evolutionary Biology, University of Regensburg, Regensburg, Germany
| |
Collapse
|
2
|
Klunk CL, Heethoff M, Hammel JU, Gorb SN, Krings W. Mechanical and elemental characterization of ant mandibles: consequences for bite mechanics. Interface Focus 2024; 14:20230056. [PMID: 38618235 PMCID: PMC11008963 DOI: 10.1098/rsfs.2023.0056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 02/16/2024] [Indexed: 04/16/2024] Open
Abstract
Mandible morphology has an essential role in biting performance, but the mandible cuticle can have regional differences in its mechanical properties. The effects of such a heterogeneous distribution of cuticle material properties in the mandible responses to biting loading are still poorly explored in chewing insects. Here, we tested the mechanical properties of mandibles of the ant species Formica cunicularia by nanoindentation and investigated the effects of the cuticular variation in Young's modulus (E) under bite loading with finite-element analysis (FEA). The masticatory margin of the mandible, which interacts with the food, was the hardest and stiffest region. To unravel the origins of the mechanical property gradients, we characterized the elemental composition by energy-dispersive X-ray spectroscopy. The masticatory margin possessed high proportions of Cu and Zn. When incorporated into the FEA, variation in E effectively changed mandible stress patterns, leading to a relatively higher concentration of stresses in the stiffer mandibular regions and leaving the softer mandible blade with relatively lower stress. Our results demonstrated the relevance of cuticle E heterogeneity in mandibles under bite loading, suggesting that the accumulation of transition metals such as Cu and Zn has a relevant correlation with the mechanical characteristics in F. cunicularia mandibles.
Collapse
Affiliation(s)
- Cristian L. Klunk
- Animal Evolutionary Ecology, Technische Universität Darmstadt, Schnittspahnstr. 3, Darmstadt 64287, Germany
| | - Michael Heethoff
- Animal Evolutionary Ecology, Technische Universität Darmstadt, Schnittspahnstr. 3, Darmstadt 64287, Germany
| | - Jörg U. Hammel
- Institute of Materials Physics, Helmholtz-Zentrum Hereon, Geesthacht, Germany
| | - Stanislav N. Gorb
- Department of Functional Morphology and Biomechanics, Zoological Institute, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1-9, Kiel 24118, Germany
| | - Wencke Krings
- Department of Functional Morphology and Biomechanics, Zoological Institute, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1-9, Kiel 24118, Germany
- Department of Cariology, Endodontology and Periodontology, Universität Leipzig, Liebigstraße 12, Leipzig, Germany
- Department of Electron Microscopy, Institute of Cell and Systems Biology of Animals, Universität Hamburg, Martin-Luther-King-Platz 3, Hamburg 20146, Germany
| |
Collapse
|
3
|
Birkenfeld V, Gorb SN, Krings W. Mandible elemental composition and mechanical properties from distinct castes of the leafcutter ant Atta laevigata (Attini; Formicidae). Interface Focus 2024; 14:20230048. [PMID: 38618230 PMCID: PMC11008964 DOI: 10.1098/rsfs.2023.0048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 12/18/2023] [Indexed: 04/16/2024] Open
Abstract
Leafcutter ant colonies are divided into castes with the individuals performing different tasks, based mostly on size. With the mandibles, the small minims care for the brood or the fungus, whereas the larger minors and mediae cut and transport plant material, with the ant size positively related to the material size. The mechanical properties and composition of the mandible cuticle have been previously tested in the soldiers as the largest caste, revealing that the cutting edges contained high contents of the cross-linking transition metal zinc (Zn). With regard to the smaller castes, no data are present. To study how the mandible size and function relates to its mechanical properties, we here tested the mandibles of minims, minors and mediae by nanoindentation. We found that the hardness (H) and Young's modulus (E) values increased with increasing ant size and that the mandible cutting edges in each caste have the highest H- and E-values. To gain insight into the origins of these properties, we characterized the elemental composition by energy-dispersive X-ray analysis, revealing that minors and mediae possessed higher content of Zn in the cutting edges in contrast to the minims containing significantly less Zn. This shows, that Zn content relates to higher mechanical property values. Additionally, it shows that all of these parameters can differ within a single species.
Collapse
Affiliation(s)
- Valentin Birkenfeld
- Department of Functional Morphology and Biomechanics, Zoological Institute, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1–9, 24118 Kiel, Germany
| | - Stanislav N. Gorb
- Department of Functional Morphology and Biomechanics, Zoological Institute, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1–9, 24118 Kiel, Germany
| | - Wencke Krings
- Department of Functional Morphology and Biomechanics, Zoological Institute, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1–9, 24118 Kiel, Germany
- Department of Cariology, Endodontology and Periodontology, Universität Leipzig, Liebigstraße 12, 04103 Leipzig, Germany
- Department of Electron Microscopy, Institute of Cell and Systems Biology of Animals, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
- Department of Mammalogy and Palaeoanthropology, Leibniz Institute for the Analysis of Biodiversity Change, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
| |
Collapse
|
4
|
Bast EM, Marshall NT, Myers KO, Marsh LW, Hurtado MW, Van Zandt PA, Lehnert MS. Diverse material properties and morphology of moth proboscises relates to the feeding habits of some macromoth and other lepidopteran lineages. Interface Focus 2024; 14:20230051. [PMID: 38618232 PMCID: PMC11008959 DOI: 10.1098/rsfs.2023.0051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 01/03/2024] [Indexed: 04/16/2024] Open
Abstract
Insects have evolved unique structures that host a diversity of material and mechanical properties, and the mouthparts (proboscis) of butterflies and moths (Lepidoptera) are no exception. Here, we examined proboscis morphology and material properties from several previously unstudied moth lineages to determine if they relate to flower visiting and non-flower visiting feeding habits. Scanning electron microscopy and three-dimensional imaging were used to study proboscis morphology and assess surface roughness patterns on the galeal surface, respectively. Confocal laser scanning microscopy was used to study patterns of cuticular autofluorescence, which was quantified with colour analysis software. We found that moth proboscises display similar autofluorescent signals and morphological patterns in relation to feeding habits to those previously described for flower and non-flower visiting butterflies. The distal region of proboscises of non-flower visitors is brush-like for augmented capillarity and exhibited blue autofluorescence, indicating the possible presence of resilin and increased flexibility. Flower visitors have smoother proboscises and show red autofluorescence, an indicator of high sclerotization, which is adaptive for floral tube entry. We propose the lepidopteran proboscis as a model structure for understanding how insects have evolved a suite of morphological and material adaptations to overcome the challenges of acquiring fluids from diverse sources.
Collapse
Affiliation(s)
- Elaine M. Bast
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | - Natalie T. Marshall
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | - Kendall O. Myers
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | - Lucas W. Marsh
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | | | | | - Matthew S. Lehnert
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| |
Collapse
|
5
|
Imirzian N, Püffel F, Roces F, Labonte D. Large deformation diffeomorphic mapping of 3D shape variation reveals two distinct mandible and head capsule morphs in Atta vollenweideri leaf-cutter worker ants. Ecol Evol 2024; 14:e11236. [PMID: 38633523 PMCID: PMC11021802 DOI: 10.1002/ece3.11236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 02/21/2024] [Accepted: 03/15/2024] [Indexed: 04/19/2024] Open
Abstract
Ants are crucial ecosystem engineers, and their ecological success is facilitated by a division of labour among sterile "workers". In some ant lineages, workers have undergone further morphological differentiation, resulting in differences in body size, shape, or both. Distinguishing between changes in size and shape is not trivial. Traditional approaches based on allometry reduce complex 3D shapes into simple linear, areal, or volume metrics; modern approaches using geometric morphometrics typically rely on landmarks, introducing observer bias and a trade-off between effort and accuracy. Here, we use a landmark-free method based on large deformation diffeomorphic metric mapping (LDDMM) to assess the co-variation of size and 3D shape in the mandibles and head capsules of Atta vollenweideri leaf-cutter ants, a species exhibiting extreme worker size-variation. Body mass varied by more than two orders of magnitude, but a shape atlas created via LDDMM on μ-CT-derived 3D mesh files revealed only two distinct head capsule and mandibles shapes-one for the minims (body mass < 1 mg) and one for all other workers. We discuss the functional significance of the identified 3D shape variation, and its implications for the evolution of extreme polymorphism in Atta.
Collapse
Affiliation(s)
| | | | - Flavio Roces
- Department of Behavioural Physiology and SociobiologyBiocenter, University of WürzburgWürzburgGermany
| | - David Labonte
- Department of BioengineeringImperial College LondonLondonUK
| |
Collapse
|
6
|
Richter A, Economo EP. The feeding apparatus of ants: an overview of structure and function. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220556. [PMID: 37839452 PMCID: PMC10577024 DOI: 10.1098/rstb.2022.0556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 06/25/2023] [Indexed: 10/17/2023] Open
Abstract
Ants are a dominant family of eusocial terrestrial insects with a diversity of ecologies, lifestyles and morphologies. Ant diet preferences range from strict carnivory through omnivory to almost complete herbivory in species feeding on seeds or exudates of plant-sucking insects. While several studies have investigated ant feeding performance on different substrates, comparatively little is known about the functional morphology of the structures involved in food uptake or their diversification across the ants. To take stock of our current knowledge, we give an overview of how adult ants ingest food, followed by a morphological description of the mouthparts, preoral space and cephalic sucking pump. The mandibles are the most prominent mouthparts and have received considerable attention in the literature, so we focus on the maxillae and labium here. We present current hypotheses for the movement patterns of these parts and discuss morphological differences among ants that may be related to their ecological diversity. Finally, we give short comparisons of the ant condition with some other insects and vertebrates, as well as an outlook summarizing gaps in our knowledge. This sets the stage for future studies elucidating the connections between ant feeding mechanisms and mouthpart evolution. This article is part of the theme issue 'Food processing and nutritional assimilation in animals'.
Collapse
Affiliation(s)
- Adrian Richter
- Biodiversity and Biocomplexity Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1, Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Evan P Economo
- Biodiversity and Biocomplexity Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1, Tancha, Onna-son, Okinawa 904-0495, Japan
| |
Collapse
|
7
|
Saccardi L, Schiebl J, Balluff F, Christ U, Gorb SN, Kovalev A, Schwarz O. Anti-Adhesive Surfaces Inspired by Bee Mandible Surfaces. Biomimetics (Basel) 2023; 8:579. [PMID: 38132517 PMCID: PMC10742288 DOI: 10.3390/biomimetics8080579] [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: 09/18/2023] [Revised: 11/15/2023] [Accepted: 11/20/2023] [Indexed: 12/23/2023] Open
Abstract
Propolis, a naturally sticky substance used by bees to secure their hives and protect the colony from pathogens, presents a fascinating challenge. Despite its adhesive nature, honeybees adeptly handle propolis with their mandibles. Previous research has shown a combination of an anti-adhesive fluid layer and scale-like microstructures on the inner surface of bee mandibles. Our aim was to deepen our understanding of how surface energy and microstructure influence the reduction in adhesion for challenging substances like propolis. To achieve this, we devised surfaces inspired by the intricate microstructure of bee mandibles, employing diverse techniques including roughening steel surfaces, creating lacquer structures using Bénard cells, and moulding resin surfaces with hexagonal patterns. These approaches generated patterns that mimicked the bee mandible structure to varying degrees. Subsequently, we assessed the adhesion of propolis on these bioinspired structured substrates. Our findings revealed that on rough steel and resin surfaces structured with hexagonal dimples, propolis adhesion was significantly reduced by over 40% compared to unstructured control surfaces. However, in the case of the lacquer surface patterned with Bénard cells, we did not observe a significant reduction in adhesion.
Collapse
Affiliation(s)
- Leonie Saccardi
- Institute of Biomaterials and Biomolecular Systems, University of Stuttgart, 70569 Stuttgart, Germany
- Department of Biomechatronic Systems, FraunhoferInstitute for Manufacturing Engineering and Automation IPA, 70569 Stuttgart, Germany
| | - Jonas Schiebl
- Department of Biomechatronic Systems, FraunhoferInstitute for Manufacturing Engineering and Automation IPA, 70569 Stuttgart, Germany
| | - Franz Balluff
- Department of Applied Coating Technology, Fraunhofer-Institute for Manufacturing Engineering and Automation (IPA), 70569 Stuttgart, Germany
| | - Ulrich Christ
- Department of Applied Coating Technology, Fraunhofer-Institute for Manufacturing Engineering and Automation (IPA), 70569 Stuttgart, Germany
| | - Stanislav N. Gorb
- Department Functional Morphology and Biomechanics, Zoological Institute, Kiel University, 24118 Kiel, Germany
| | - Alexander Kovalev
- Department Functional Morphology and Biomechanics, Zoological Institute, Kiel University, 24118 Kiel, Germany
| | - Oliver Schwarz
- Department of Biomechatronic Systems, FraunhoferInstitute for Manufacturing Engineering and Automation IPA, 70569 Stuttgart, Germany
| |
Collapse
|
8
|
Klunk CL, Argenta MA, Rosumek FB, Schmelzle S, van de Kamp T, Hammel JU, Pie MR, Heethoff M. Simulated biomechanical performance of morphologically disparate ant mandibles under bite loading. Sci Rep 2023; 13:16833. [PMID: 37803099 PMCID: PMC10558566 DOI: 10.1038/s41598-023-43944-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 09/30/2023] [Indexed: 10/08/2023] Open
Abstract
Insects evolved various modifications to their mouthparts, allowing for a broad exploration of feeding modes. In ants, workers perform non-reproductive tasks like excavation, food processing, and juvenile care, relying heavily on their mandibles. Given the importance of biting for ant workers and the significant mandible morphological diversity across species, it is essential to understand how mandible shape influences its mechanical responses to bite loading. We employed Finite Element Analysis to simulate biting scenarios on mandible volumetric models from 25 ant species classified in different feeding habits. We hypothesize that mandibles of predatory ants, especially trap-jaw ants, would perform better than mandibles of omnivorous species due to their necessity to subdue living prey. We defined simulations to allow only variation in mandible morphology between specimens. Our results demonstrated interspecific differences in mandible mechanical responses to biting loading. However, we found no evident differences in biting performance between the predatory and the remaining ants, and trap-jaw mandibles did not show lower stress levels than other mandibles under bite loading. These results suggest that ant feeding habit is not a robust predictor of mandible biting performance, a possible consequence of mandibles being employed as versatile tools to perform several tasks.
Collapse
Affiliation(s)
- C L Klunk
- Graduate Program in Ecology and Conservation, Universidade Federal do Paraná, Centro Politécnico, Av. Cel. Francisco H. dos Santos, 100 - Jardim das Américas, Curitiba, PR, 81531-980, Brazil.
- Animal Evolutionary Ecology, Technische Universität Darmstadt, Schnittspahnstr. 3, 64287, Darmstadt, Germany.
| | - M A Argenta
- Department of Civil Construction, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - F B Rosumek
- Department of Ecology and Zoology, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - S Schmelzle
- Animal Evolutionary Ecology, Technische Universität Darmstadt, Schnittspahnstr. 3, 64287, Darmstadt, Germany
| | - T van de Kamp
- Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
- Laboratory for Applications of Synchrotron Radiation (LAS), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - J U Hammel
- Institute of Materials Physics, Helmholtz-Zentrum Hereon, Geesthacht, Germany
| | - M R Pie
- Biology Department, Edge Hill University, Ormskirk, Lancashire, UK
| | - M Heethoff
- Animal Evolutionary Ecology, Technische Universität Darmstadt, Schnittspahnstr. 3, 64287, Darmstadt, Germany.
| |
Collapse
|
9
|
Klunk CL, Argenta MA, Casadei‐Ferreira A, Pie MR. Mechanical demands of bite in plane head shapes of ant (Hymenoptera: Formicidae) workers. Ecol Evol 2023; 13:e10162. [PMID: 37293120 PMCID: PMC10244895 DOI: 10.1002/ece3.10162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/16/2023] [Accepted: 05/24/2023] [Indexed: 06/10/2023] Open
Abstract
Food processing can exert significant evolutionary pressures on the morphological evolution of animal appendages. The ant genus Pheidole displays a remarkable degree of morphological differentiation and task specialization among its workers. Notably, there is considerable variation in head shape within worker subcastes of Pheidole, which could affect the stress patterns generated by bite-related muscle contraction. In this study, we use finite element analysis (FEA) to investigate the effect of the variation in head plane shape in stress patterns, while exploring the morphospace of Pheidole worker head shapes. We hypothesize that the plane head shapes of majors are optimized for dealing with stronger bites. Furthermore, we expect that plane head shapes at the edges of each morphospace would exhibit mechanical limitations that prevent further expansion of the occupied morphospace. We vectorized five head shapes for each Pheidole worker type located at the center and edges of the corresponding morphospaces. We conducted linear static FEA to analyze the stresses generated by mandibular closing muscle contraction. Our findings indicate that plane head shapes of majors exhibit signs of optimization to deal with stronger bites. Stresses are distinctly directed along the lateral margins of the head, following the direction of muscle contraction, whereas the stresses on the plane head shapes of minors tend to concentrate around the mandibular articulations. However, the comparatively higher stress levels observed on majors' plane head shapes suggest a demand for cuticular reinforcement, like increased cuticle thickness or sculpturing pattern. Our results align with the expectations regarding the main colony tasks performed by each worker subcaste, and we find evidence of biomechanical limitations on extreme plane head shapes for majors and minors.
Collapse
Affiliation(s)
- Cristian L. Klunk
- Graduate Program in Ecology and ConservationUniversidade Federal do ParanáCuritibaBrazil
| | - Marco A. Argenta
- Department of Civil ConstructionUniversidade Federal do ParanáCuritibaBrazil
| | - Alexandre Casadei‐Ferreira
- Biodiversity and Biocomplexity UnitOkinawa Institute of Science and Technology Graduate UniversityOnnaJapan
| | - Marcio R. Pie
- Department of BiologyEdge Hill UniversityOrmskirkUK
- Department of ZoologyUniversidade Federal do ParanáCuritibaBrazil
| |
Collapse
|
10
|
Marcé-Nogué J. One step further in biomechanical models in palaeontology: a nonlinear finite element analysis review. PeerJ 2022; 10:e13890. [PMID: 35966920 PMCID: PMC9373974 DOI: 10.7717/peerj.13890] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/21/2022] [Indexed: 01/19/2023] Open
Abstract
Finite element analysis (FEA) is no longer a new technique in the fields of palaeontology, anthropology, and evolutionary biology. It is nowadays a well-established technique within the virtual functional-morphology toolkit. However, almost all the works published in these fields have only applied the most basic FEA tools i.e., linear materials in static structural problems. Linear and static approximations are commonly used because they are computationally less expensive, and the error associated with these assumptions can be accepted. Nonetheless, nonlinearities are natural to be used in biomechanical models especially when modelling soft tissues, establish contacts between separated bones or the inclusion of buckling results. The aim of this review is to, firstly, highlight the usefulness of non-linearities and secondly, showcase these FEA tool to researchers that work in functional morphology and biomechanics, as non-linearities can improve their FEA models by widening the possible applications and topics that currently are not used in palaeontology and anthropology.
Collapse
Affiliation(s)
- Jordi Marcé-Nogué
- Department of Mechanical Engineering, Universitat Rovira i Virgili Tarragona, Tarragona, Catalonia, Spain,Institut Català de Paleontologia, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Catalonia, Spain
| |
Collapse
|
11
|
Wang Z, Zhan Y, Yang Y, Wu J. Hollow mandibles: Structural adaptation to high-speed and powerful strike in the trap-jaw ant Odontomachus monticola. JOURNAL OF INSECT PHYSIOLOGY 2022; 141:104426. [PMID: 35907587 DOI: 10.1016/j.jinsphys.2022.104426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 07/18/2022] [Accepted: 07/24/2022] [Indexed: 06/15/2023]
Abstract
The trap-jaw ant Odontomachus monticola manipulates its hollow mandibles to generate extremely high speed to impact various objects through a catapult mechanism, making the violent collision occur between the mandible and the impacted objects, which increases the risk of structural failure. However, how the ant balances the trade-off between the powerful clamping and impact resistance by using this hollow structure remains elusive. In this combined experimental and theoretical investigation, we revealed that the hollowness ratio of the mandible plays an essential role in counterbalancing the trade-off. Micro-CT and high-speed images suggested that the hollow mandibles facilitate a high angular acceleration to 108 rad/s2 for an enormous clamping force. However, this hollowness might challenge the structural strength while collision occurs. We found that under the same actuating energy, the von Mises stress of the object collided by the natural mandible striking can reach up to 2.9 times that generated by the entirely solid mandible. We defined the efficiency ratio of the von Mises stress on the impacted object to that on the mandible and found the hollow mandible achieves a more robust balance between powerful clamping and impact resistance compared to the solid mandible.
Collapse
Affiliation(s)
- Zixin Wang
- School of Engineering and Technology, China University of Geosciences (Beijing), Beijing 100083, PR China
| | - Yuping Zhan
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Shenzhen 518107, PR China
| | - Yunqiang Yang
- School of Engineering and Technology, China University of Geosciences (Beijing), Beijing 100083, PR China.
| | - Jianing Wu
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Shenzhen 518107, PR China.
| |
Collapse
|
12
|
Finite element analysis relating shape, material properties, and dimensions of taenioglossan radular teeth with trophic specialisations in Paludomidae (Gastropoda). Sci Rep 2021; 11:22775. [PMID: 34815469 PMCID: PMC8611077 DOI: 10.1038/s41598-021-02102-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 11/10/2021] [Indexed: 01/18/2023] Open
Abstract
The radula, a chitinous membrane with embedded tooth rows, is the molluscan autapomorphy for feeding. The morphologies, arrangements and mechanical properties of teeth can vary between taxa, which is usually interpreted as adaptation to food. In previous studies, we proposed about trophic and other functional specialisations in taenioglossan radulae from species of African paludomid gastropods. These were based on the analysis of shape, material properties, force-resistance, and the mechanical behaviour of teeth, when interacting with an obstacle. The latter was previously simulated for one species (Spekia zonata) by the finite-element-analysis (FEA) and, for more species, observed in experiments. In the here presented work we test the previous hypotheses by applying the FEA on 3D modelled radulae, with incorporated material properties, from three additional paludomid species. These species forage either on algae attached to rocks (Lavigeria grandis), covering sand (Cleopatra johnstoni), or attached to plant surface and covering sand (Bridouxia grandidieriana). Since the analysed radulae vary greatly in their general size (e.g. width) and size of teeth between species, we additionally aimed at relating the simulated stress and strain distributions with the tooth sizes by altering the force/volume. For this purpose, we also included S. zonata again in the present study. Our FEA results show that smaller radulae are more affected by stress and strain than larger ones, when each tooth is loaded with the same force. However, the results are not fully in congruence with results from the previous breaking stress experiments, indicating that besides the parameter size, more mechanisms leading to reduced stress/strain must be present in radulae.
Collapse
|