Structural background of intraspecific color polymorphism and the driver of geographic patterns in a shining leaf chafer.

Background: The phenomenon of color polymorphism has been extensively documented in a range of animal species. A series of hypotheses have been proposed to explain potential functions of color variations in diverse habitats. However, the generation of color is an intricate physical, chemical and biological process.

How Does a Delicate Insect Wing Resist Damage? Chitin Orientation Is Adapted to the Mechanical Demands at the Nanoscale.

Insect wings achieve an extraordinary balance between structural robustness and lightweight flexibility, enabling efficient and durable flight. This performance arises from their hierarchical composite architecture, where nanoscale chitin fiber orientations play a critical role in adapting to complex mechanical demands. Using scanning X-ray micro- and nano-diffraction, the spatial distribution and orientation of chitin fibers in the hindwing of the desert locust Schistocerca gregaria are systematically mapped.

Structural and Adhesive Properties of Cellulosic Mucilage: A Molecular-Level Investigation.

Several plant seeds release a mucilaginous envelope upon hydration, rich in pectin and stabilized by cellulose fibers, generating adhesion. However, the mechanisms governing mucilage adhesion remain unclear. Using a multibody dissipative particle dynamics (MDPD) model, we investigated the roles of cellulose, pectin, and water in seed adhesion.

Morphology and material composition of raptorial foreleg cuticles in praying mantises Gongylus gongylodes and Sphodromantis lineola.

Praying mantises (Mantodea, Insecta) are capable of capturing larger invertebrates and also smaller vertebrates with their raptorial forelegs. Forelegs may exhibit morphological adaptations based on the type of prey they prefer (e.g.

Functional leg design in dung beetles: Morphological adaptations to food relocation behavior.

Dung beetles are coprophagous insects that reproduce and feed on vertebrate faeces. The dependency on the same ephemeral food source leads to frequent contact between individuals and thus intense competition. As a consequence, different strategies of food relocation (horizontal and vertical) have evolved, that put different stresses on the functional morphology of the extremities depending on whether dung is rolled as a ball, carried in fragments or dragged directly into the underground burrow.

The ectoparasitic seal louse, Echinophthirius horridus, relies on a sealed tracheal system and spiracle closing apparatus for underwater respiration.

Marine mammals host a diverse array of parasites engaged in a continuous evolutionary arms race. However, our understanding of the biology of parasitic insects associated with marine mammals, particularly their adaptations to challenging marine environments, remains limited. The seal louse, Echinophthirius horridus, which infests true seals, is one of thirteen insect species capable of enduring prolonged dives in open seas.

Wear-coping mechanisms and functional morphology of the radular teeth of (Neritimorpha, Gastropoda).

In most molluscan species, the food is manipulated and taken in by the radula, a chitinous structure exhibiting diverse morphologies and compositions. The teeth of Patellogastropoda and Polyplacophora are well studied, with heavy mineralization reducing wear and failure. However, some gastropod taxa possess unmineralized teeth, even though they forage from rocks.

Structure and material composition of oral disc structures in selected Anuran tadpoles (Amphibia).

This study investigates the material composition of the keratinous teeth and jaw sheaths of Anuran tadpoles, for the first time. Using scanning electron microscopy (SEM), confocal laser scanning microscopy (CSLM), and energy dispersive X-ray spectroscopy (EDX), the oral discs of eight species were analysed. SEM analysis revealed structural diversity, including different tooth microstructures, which may reflect functional adaptations to different mechanical loads.

Biological Attachment Systems and Biomimetics-In Memory of William Jon P. Barnes.

Any system preventing the separation of two surfaces may be defined as an attachment system [...

Material composition of the endophytic ovipositor in the damselfly Calopteryx splendens (Odonata, Calopterygidae).

Natural selection has favoured the incorporation of ions, including transition metals, in materials of various biological structures susceptible to mechanical fracture to enhance their failure and wear resistance. With regards to insects, only a few taxa have been investigated. The objective of this study was to analyse the biomechanical properties of the ovipositor in the damselfly Calopteryx splendens (Harris, 1780) (Odonata, Zygoptera, Calopterygidae) through nanoindentation and to ascertain the elemental composition gradient within the cuticle using energy-dispersive X-ray spectroscopy.

Advances in Biomimetics: The Power of Diversity.

Biomimetics research on living systems attempts to transfer their properties and functions to engineering applications [...

The influence of pectins and cellulose fibers in the mechanical and adhesive properties of seed mucilage.

Several plant seeds release a mucilaginous envelope through hydration, rich in pectins and stabilized by cellulose fibers. This mucilage aids in seed protection, development, and adhesion for dispersal. This study aimed to separate the effects of pectins and cellulose fibers by using pectinase to remove mucilage pectins, leaving cellulose arrays, and performing wet and dry pull-off force measurements on seeds of three plant species: Salvia hispanica (chia), Collomia grandiflora (collomia), and Linum usitatissimum (flax).

Kinematics and directionality of body turning in water striders (Gerris argentatus) on the water surface.

Water striders inhabit the elastic surface tension film of water, sharing their environment with other aquatic organisms. Their survival relies heavily on swift maneuverability and navigation around floating obstacles, which aids in the exploration of their habitat and in escaping from potential threats. Their high agility is strongly based on the ability to execute precise turns, enabling effective directional control.

Natural nanofibers embedded in the seed mucilage envelope: composite hydrogels with specific adhesive and frictional properties.

The increasing interests in natural, biodegradable, non-toxic materials that can find application in diverse industry branches, for example, food, pharmacy, medicine, or materials engineering, has steered the attention of many scientists to plants, which are a known source of natural hydrogels. Natural hydrogels share some features with synthetic hydrogels, but are more easy to obtain and recycle. One of the main sources of such hydrogels are mucilaginous seeds and fruits, which produce after hydration a gel-like, transparent capsule, the so-called mucilage envelope.

Adhesion of the mucilage envelope of seeds probed by sum frequency generation spectroscopy.

The attachment of seeds to natural surfaces is important for the reproductive success of plants. This study investigates the adhesion mechanisms of seed mucilage to CaF and polystyrene surfaces, using sum frequency generation (SFG) vibrational spectroscopy and pull-off force measurements. The results show that the adhesion is driven by the formation of crystalline cellulose at the interface.

Comparative Morphology of the Extrinsic and Intrinsic Leg Musculature in Dictyoptera (Insecta: Blattodea, Mantodea).

Insect legs, as primarily locomotory devices, can show a tremendous variety of morphological modifications providing a multitude of usages. The prehensile raptorial forelegs of praying mantises (Mantodea) are a prominent example of true multifunctionality since they are used for walking while being efficient prey-capturing and grasping devices. Although being mostly generalist arthropod predators, various morphological adaptations due to different environmental conditions occur across Mantodea.

Pectin Mucilage Adhesion on a Flat Substrate: A Molecular Simulation Approach to Plant-Seed Adhesion.

We investigate the adhesion of pectin-mucilage-coated seeds to substrate surfaces, focusing on the effect of water content. It is known that the adhesion of pectin mucilage increases with water loss, eventually dropping to zero beyond a certain point. To explore this phenomenon, we develop and parametrize a coarse-grained many-body dissipative-particle dynamics (MDPD) model.

Double-spiral as a bio-inspired functional element in engineering design.

Spiral, one of the most well-known functional patterns in nature that can be observed in structures such as the proboscis of lepidoptera and snail shells or as vortices forming in flowing fluids, has long served as a source of inspiration for humans in the creation of numerous spiral-based designs. Double-spiral is a design derived from spirals, which has been previously presented and utilized as a compliant joint. Advantageous properties of double-spirals, such as easily adjustable design, multiple degrees of freedom, reversible extensibility, and tunable deformability make them promising candidates for the development of mechanically intelligent structures that exhibit unique behavior and reach desired functions, such as soft grippers, continuum manipulators, energy-dissipative structures, and foldable metamaterials.

Mandible composition and properties in two selected praying mantises (Insecta, Mantodea).

Insects process their food with their cuticle-based mouthparts. These feeding structures reflect their diversity and can, in some cases, showcase adaptations in material composition, mechanical properties, and shape to suit their specific dietary preferences. To pave the way to deeply understand the interaction between mouthparts and food and to determine potential adaptations of the structures to the food, this study focuses on the mandibles of two praying mantis species.

Diversity of attachment systems in heelwalkers (Mantophasmatodea) - highly specialized, but uniform.

Background: Heelwalkers possess a highly modified tarsal attachment system. All extant species lift the distalmost tarsomere permanently off the substrate and primarily use their euplantulae for locomotion. The combination of a smooth adhesive pad (arolium) on the pretarsus and fibrillary attachment pads on the euplantulae offers valuable insights for translational approaches, but its infra-order diversity remains unexplored.

Leg Attachment Devices of Tiger Beetles (Coleoptera, Cicindelidae) and Their Relationship to Their Habitat Preferences.

The ability of many insects to adhere vertically or even upside down to smooth substrates is closely related to the morphology and distribution of the adhesive structures on their legs. During locomotion, the legs are in direct contact with different substrates, and it is hypothesized that the adhesive structures have been evolved as an adaption to smooth substrates in specific environments. To investigate whether there is a relationship between the presence of adhesive structures and the combined effects of different environments and mating behavior, we compared five species of tiger beetles belonging to two tribes living in arboreal and non-arboreal environments, respectively.

WingAnalogy: a computer vision-based tool for automated insect wing asymmetry and morphometry analysis.

WingAnalogy is a computer tool for automated insect wing morphology and asymmetry analysis. It facilitates project management, enabling users to import pairs of wing images obtained from individual insects, such as left and right, fore- and hindwings. WingAnalogy employs image processing and computer vision to segment wing structures and extract cell boundaries, and junctions.

Radular Tooth Coating in Members of Dendronotidae and Flabellinidae (Nudibranchia, Gastropoda, Mollusca).

Nudibranchs, with their mesmerizing diversity and ecological significance, play crucial roles in marine ecosystems. Central to their feeding prowess is the radula, a chitinous structure with diverse morphologies adapted to prey preferences and feeding strategies. This study focuses on elucidating wear coping mechanisms in radular teeth of carnivorous molluscs, employing Dendronotus lacteus (Dendronotidae) and Flabellina affinis (Flabellinidae) as model species.