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Abstract Because plants are considered immobile, they remain underrepresented as concept generators for soft robots and soft machines. However, plants show a great variety of movements exclusively based on elastic deformation of regions within their moving organs. The absence of gliding parts, as found in the joints of vertebrates and insects, prevents stress concentration and attrition. Since plants have no central control unit (brain), stimulus-sensing, decision-making and reaction usually take place noncentrally in the hierarchically structured materials systems of the moving organs, in what can be regarded as an example of physical intelligence. These characteristics make plants interesting models for a new group of soft robots and soft machines that differ fundamentally from those inspired by animals. The potential of such plant-inspired soft robots and machines is shown in six examples and is illustrated by examples applied in architecture and medicine. Graphical abstract

Plants are exposed to various environmental stresses. Leaves immediately respond to mechano-stimulation, such as wind and touch, by bending and twisting or acclimate over a longer time period by thigmomorphogenetic changes of mechanical and geometrical properties. We selected the peltate leaves of Pilea peperomioides for a comparative analysis of mechano-induced effects on morphology, anatomy, and biomechanics of petiole and transition zone. The plants were cultivated for 6 weeks in a phytochamber divided into four treatment groups: control (no stimulus), touch stimulus (brushing every 30 s), wind stimulus (constant air flow of 4.6 m s−1), and a combination of touch and wind stimuli. Comparing the four treatment groups, neither the petiole nor the transition zone showed significant thigmomorphogenetic acclimations. However, comparing the petiole and the transition zone, the elastic modulus (E), the torsional modulus (G), the E/G ratio, and the axial rigidity (EA) differed significantly, whereas no significant difference was found for the torsional rigidity (GK). The twist-to-bend ratios (EI/GK) of all petioles ranged between 4.33 and 5.99, and of all transition zones between 0.67 and 0.78. Based on the twist-to-bend ratios, we hypothesize that bending loads are accommodated by the petiole, while torsional loads are shared between the transition zone and petiole.

Faced with the environmental challenges posed by climate change, architects are creating nature-based solutions for urban areas, such as transforming living trees into artificial architectural structures. In this study, we have analyzed stem pairs of five tree species conjoined for more than eight years by measuring the stem diameters below and above the resulting inosculation and by calculating the respective diameter ratio. Our statistical analyses reveal that Platanus × hispanica and Salix alba stems do not differ significantly in diameter below inosculation. However, in contrast to P. × hispanica, the diameters of the conjoined stems above inosculation differ significantly in S. alba. We provide a binary decision tree based on diameter comparisons above and below inosculation as a straightforward tool for identifying the likelihood of full inosculation with water exchange. Moreover, we have compared branch junctions and inosculations by means of anatomical analyses, micro-computed tomography, and 3D reconstructions showing similarities in the formation of common annual rings that increase the capacity for water exchange. Due to the highly irregular cell arrangement in the center of the inosculations, cells cannot be assigned clearly to either of the stems. In contrast, cells in the center of branch junctions can always be attributed to one of the branches.

The proclamation of the Anthropocene occurred simultaneously with consideration of the contribution of biomimetic products towards a more sustainable future. One major challenge is the purposeful handling of consumer goods in order to save resources and avoid waste. This can be achieved by damage control. In recent years, damage control exerted by plants has turned out to be a treasure trove of functional principles that can be transferred to technical systems. Plants prevent damage to themselves through the formation of gradient transitions by means of geometrical characteristics and biomechanical properties. Furthermore, they can respond structurally and mechanically to withstand higher stresses without damage. Damage management in plants includes the self-repair of wounds and the formation of abscission zones, the latter ensuring the controlled disintegration of biological materials systems. Plant-inspired solutions of damage control can contribute to Sustainable Development Goal 12 ‘responsible consumption and production patterns’ through the efficient use of resources and the reduction of waste generation.

During the evolution of land plants many body plans have been developed. Differences in the cross-sectional geometry and tissue pattern of plant axes influence their flexural rigidity, torsional rigidity and the ratio of both of these rigidities, the so-called twist-to-bend ratio. For comparison, we have designed artificial cross-sections with various cross-sectional geometries and patterns of vascular bundles, collenchyma or sclerenchyma strands, but fixed percentages for these tissues. Our mathematical model allows the calculation of the twist-to-bend ratio by taking both cross-sectional geometry and tissue pattern into account. Each artificial cross-section was placed into a rigidity chart to provide information about its twist-to-bend ratio. In these charts, artificial cross-sections with the same geometry did not form clusters, whereas those with similar tissue patterns formed clusters characterized by vascular bundles, collenchyma or sclerenchyma arranged as one central strand, as a peripheral closed ring or as distributed individual strands. Generally, flexural rigidity increased the more the bundles or fibre strands were placed at the periphery. Torsional rigidity decreased the more the bundles or strands were separated and the less that they were arranged along a peripheral ring. The calculated twist-to-bend ratios ranged between 0.85 (ellipse with central vascular bundles) and 196 (triangle with individual peripheral sclerenchyma strands).

Premise Because of their own weight and additional wind forces, plants are exposed to various bending and torsional loads that sometimes require contradictory structural characteristics and mechanical properties. The resulting trade-off between flexural and torsional rigidity can be quantified and compared using the dimensionless twist-to-bend ratio. Methods The flexural rigidity of the stems of Carex pendula was determined by 2-point bending tests. Additionally, 4-point bending tests and torsional tests were carried out on segments of two internodes directly below the inflorescences to measure flexural and torsional rigidity. Anatomical investigations were performed to quantify the cross-sectional distribution of their tissues. Results The flexural rigidity of the stems, segments of the apical internode 1, and the more basal internode 2 differed significantly from each other, whereas the bending elastic moduli were not significantly different. The torsional rigidity of segments of internode 2 was a factor of 3.3 higher than that of internode 1, whereas the torsional moduli did not differ significantly. The twist-to-bend ratios of segments of internode 1 and 2 reached values between 85 and 403. Light microscopic investigations revealed a triangular stem possessing individual sclerenchyma strands, with internode 2 having significantly more strands than internode 1. Conclusions In the case of Carex pendula, flexural and torsional rigidity are adapted to the given mechanical constraints by significant changes in morphometric variables (axial and polar second moment of area, number of sclerenchyma strands), whereas the material properties (bending and torsional modulus) do not change markedly along the stem.

During biological evolution, plants evolved various types of wound reactions. This study focuses on the self-healing of plant fibers in the model plant Leonurus cardiaca L. In one of the square-shaped internodes of each plant, all four prominent strands of the collenchyma were damaged by a razor blade with a central incision in a longitudinal direction. After 20 to 24 days, the morphology, anatomy, and biomechanics of the healed internodes were compared with undamaged controls. Stem height increased highly significantly in the healed and control plants, although the healed internodes were significantly shorter than the respective control internodes. Light microscopy examination of the wounded region revealed permanent gaping of the wound and the formation of a distinct boundary layer. Four-point-bending tests showed a significantly lower flexural rigidity (self-healing efficiency = 44%) and a highly significantly lower bending elastic modulus (self-healing efficiency = 66%) for the healed internodes compared with the controls, although the axial second moments of area did not differ significantly (self-healing efficiency = 82%). After a healing period of three weeks, recovery of the morphological–anatomical characteristics and mechanical properties of the healed internodes was incomplete compared with the undamaged control samples. Nevertheless, the self-healing efficiency seemed to be sufficient to ensure the integrity of the stem during the entire growth period.

The building industry is one of the main contributors to worldwide resource consumption and anthropogenic climate change. Therefore, sustainable solutions in construction are particularly urgent. Inspired by the success principles of living nature, biologists and engineers present here an interdisciplinary work: The sustainability assessment of a bio-inspired material technology called graded concrete, which was developed at ILEK. Gradient structural materials can be found in plants on different hierarchical levels, providing a multitude of creative solutions for technology. Graded concrete applies this biological concept of structural optimization to the interior structure of concrete components to minimize material and resource expenditure. To evaluate the sustainability of this innovation, a newly developed quantitative Bio-inspired Sustainability Assessment (BiSA) method is applied. It focuses on the relationship of environmental, social and economic functions and the corresponding burdens quantified basing on life cycle assessment. The BiSA of graded concrete slabs shows significant improvements over conventional concrete for the applied use case. While an overall reduction of environmental burdens by 13% is expected, economic burdens can be reduced by up to 40% and social burdens by 35.7%. The assessment of the graded concrete technology identifies its potential with regard to sustainable construction. The presented work provides a blueprint for the interdisciplinary, integrative work on sustainable, bio-inspired innovations. It shows that the synergies of bio-inspiration and BiSA within technical product development can be fruitful.

The European mistletoe (Viscum album) is an epiphytic hemiparasite that attaches to its host by an endophytic system. Two aspects are essential for its survival: the structural integrity of the host–parasite interface must be maintained during host growth and the functional integrity of the interface must be maintained during ontogeny and under mechanical stress. We investigated the mechanical properties of the mistletoe–host interaction. Intact and sliced mistletoe–host samples, with host wood as reference, were subjected to tensile tests up to failure. We quantified the rough fractured surface by digital microscopy and analysed local surface strains by digital image correlation. Tensile strength and deformation energy were independent of mistletoe age but exhibited markedly lower values than host wood samples. Cracks initiated at sites with a major strain of about 30%, especially along the mistletoe–host interface. The risk of sudden failure was counteracted by various sinkers and a lignification gradient that smooths the differences in the mechanical properties between the two species. Our results improve the understanding of the key mechanical characteristics of the host–mistletoe interface and show that the mechanical connection between the mistletoe and its host is age-independent. Thus, functional and structural integrity is ensured over the lifetime of the mistletoe.

Since most plant movements take place through an interplay of elastic deformation and strengthening tissues, they are thus ideal concept generators for biomimetic hingeless actuators. In the framework of a biomimetic biology push process, we present the transfer of the functional movement principles of hollow tubular geometries that are surrounded by a net-like structure. Our plant models are the recent genera Ochroma (balsa) and Carica (papaya) as well as the fossil seed fern Lyginopteris oldhamia, which hold a net of macroscopic fiber structures enveloping the whole trunk. Asymmetries in these fiber nets, which are specifically caused by asymmetric growth of the secondary wood, enable the up-righting of inclined Ochroma and Carica stems. In a tubular net-like structure, the fiber angles play a crucial role in stress–strain relationships. When braided tubes are subjected to internal pressure, they become shorter and thicker if the fiber angle is greater than 54.7°. However, if the fiber angle is less than 54.7°, they become longer and thinner. In this article, we use straightforward functional demonstrators to show how insights into functional principles from living nature can be transferred into plant-inspired actuators with linear or asymmetric deformation.

In the course of biological evolution, plant stems have evolved mechanical properties and an internal structure that makes them resistant to various types of failure. The mechanisms involved during damage development and failure in bending are complex and incompletely understood. The work presented builds on a theoretical framework outlined by Ennos and van Casteren, who applied engineering mechanics theory to explain why different woody stems fail in different ways. Our work has extended this approach, applying it to a detailed analysis of one particular species: Fuchsia magellanica var. gracilis. When subjected to three-point bending, stems of this species exhibited one of two failure mechanisms: a plastic hinge or a greenstick fracture. We developed a predictive model using a computer simulation and a mathematical analysis using the theory of plastic bending. Required material properties were obtained from tests, the literature and imaging techniques. We found that greenstick fractures are more likely to occur in more lignified stems with a higher density. We discovered a new failure mode: an internal crack caused by tensile transverse stress. This work helps in understanding how plants have evolved their bending resistance and may assist in the creation of novel engineering structures inspired by these principles.

Sustainable development is a global challenge addressed by the 2030 Agenda with internationally adopted goals. The consideration of the three major sustainability strategies of efficiency, consistency, and sufficiency can guide us toward more sustainable policy approaches, product manufacturing, service offers, and consumption lifestyles. We select the growth form “liana”, which has evolved several times independently, to identify traits of lianas and general biological concepts derived therefrom. Even though sustainability is an anthropocentric approach and does not exist in biology, we can attribute biological concepts to sustainability strategies. The biological concepts of lightweight construction, modularity, function-related tissue formation, and trade-off can be attributed to efficiency; the concepts of zero waste, best fit, and damage repair to consistency; and the change of growth form and the concept of less is more and good enough to sufficiency. We discuss the analogies between parasitic architecture and the “structural parasitism” of lianas on host trees and between polymers with switchable autonomous properties and ontogenetic changes in the lianescent growth form. Efficiency can be analyzed quantitatively and consistency qualitatively, whereas sufficiency, as an aspect of human consumption patterns, cannot be mathematically measured. Biological concepts can thus serve as a source of inspiration for improving sustainability in the technosphere.

During biological evolution, plants have developed a wide variety of body plans and concepts that enable them to react or adapt to changing environmental conditions. Their morphological-anatomical and mechanical adaptations to conflicting conditions are especially interesting. A good example is the trade-off between flexural and torsional rigidity, as represented by the dimensionless twist-to-bend ratio. We have developed geometric models of a plant tissue reflecting the 2D situation of triangular cross-sections comprising of a parenchymatous matrix with vascular bundles surrounded by an epidermis and analysed them by using mathematical models (finite element analysis) to measure the effect of either reinforcements of the epidermal tissue or fibre reinforcements such as collenchyma and sclerenchyma on the twist-to-bend ratio. The change from an epidermis to a covering tissue of corky periderm increases both the flexural and the torsional rigidity and decreases the twist-to-bend ratio. Furthermore, additional fibre reinforcement strands in a parenchymatous ground tissue lead to a strong increase of the flexural and a weaker increase of the torsional rigidity and thus resulting in a marked increase of the twist-to-bend ratio. Within the developed model, a reinforcement by 49 sclerenchyma fibre strands or 24 collenchyma fibre strands is optimal in order to achieve high twist-to-bend ratios. Dependent on the mechanical quality of the fibres, the twist-to-bend ratio of collenchyma-reinforced axes is noticeably smaller, with collenchyma having an elastic modulus that is approximately 20 times smaller than that of sclerenchyma.

Within the framework of a biomimetic top-down approach, our study started with the technical question of the development of a hinge-free and compliant actuator inspired by plant movements. One meaningful biological concept generator was the opening and closing movements of the leaf halves of grasses. Functional morphological investigations were carried out on the selected model plant Sesleria nitida . The results formed the basis for further clarifying the functional movement principle with a particular focus on the role of turgor changes in bulliform cells on kinetic amplification. All findings gained from the investigations of the biological model were incorporated into a finite-element analysis, as a prerequisite for the development of a pneumatic cellular actuator. The first prototype consisted of a row of single cells positioned on a plate. The cells were designed in such a way that the entire structure bent when the pneumatic pressure applied to each individual cell was increased. The pneumatic cellular actuator thus has the potential for applications on an architectural scale. It has subsequently been integrated into the midrib of the facade shading system Flectofold in which the bending of its midrib controls the hoisting of its wings.

Within the Aizoaceae, the genus Delosperma exhibits a vast diversification colonizing various ecological niches in South-Africa and showing evolutionary adaptations to dry habitats that might include rapid self-sealing. Leaves of Delosperma react to external damage by the bending or contraction of the entire leaf until wound edges are brought into contact. A study of leaf morphology and anatomy, biomechanics of entire leaves and individual tissues and self-sealing kinematics after a ring incision under low and high relative humidity (RH) was carried out comparing the closely related species Delosperma cooperi and Delosperma ecklonis, which are indigenous to semi-arid highlands and regions with an oceanic climate, respectively. For both species, the absolute contractions of the examined leaf segments (&ldquo, apex&rdquo, &ldquo, incision&rdquo, base&rdquo, ) were more pronounced at low RH levels. Independent of the given RH level, the absolute contractions within the incision region of D. cooperi were significantly higher than in all other segments of this species and of D. ecklonis. The more pronounced contraction of D. cooperi leaves was linked mainly to the elastic properties of the central vascular strand, which is approximately twice as flexible as that of D. ecklonis leaves.

A numerical computer model was developed in order to describe the complex self-sealing mechanism of injured Delosperma cooperi leaves. For this purpose, the leaf anatomy was simplified to a model consisting of five concentric tissue layers. Specific parameters (modulus of elasticity, permeability, porosity, etc.) were assigned to each tissue type for modelling its physical properties. These parameters were either determined experimentally from living plant material or taken from literature. The developed computer model considers the leaf as a liquid-filled porous body within a continuum approach in order to determine the governing equations. The modelling of the wound accounts for both the injury of peripheral tissues and the free surfaces caused by the incision. The loss of water through these free surfaces initiates the self-sealing process. It is further shown that the tissue permeability and the reflection coefficient (relative permeability of a cell membrane for solutes) are the determining parameters of the self-sealing process, whereas the modulus of elasticity has a negligible influence. Thus, the self-sealing mechanism is a hydraulically driven process which leads to a local (incision region) and global (total leaf) contraction of the leaf. The accuracy of the modelled self-sealing process was validated by comparing simulation results with experiments conducted on natural plant leaves. The results will serve as valuable input for developing novel, bio-inspired technical products with self-sealing function.

Objectives We sought to characterize a histologic pattern of mid- and deep-zone gastritis, distinct from the typical pattern of Helicobacter pylori or autoimmune gastritis and to see if it had any clinicopathologic association(s). Methods We analyzed inflammatory patterns and composition, excluded autoimmune gastritis using immunohistochemistry, and reviewed the medical record for demographics, medical/surgical history, presenting symptoms, endoscopic findings, and medications for 28 cases. Results All cases had inflammation in the middle and/or deep mucosal zones with sparing of the superficial/pit compartment. Subfeatures included corpus or antral predominance, pangastric involvement, prominence of a subset(s) of inflammatory cells, and degree of epithelial injury. Of 28 patients, 13 had autoimmune disease(s), autoantibodies, or both. There was no other unifying clinical feature. Conclusions This unique pattern of gastritis should be distinguished from other entities such as H pylori and autoimmune gastritis. At least a subset may be an autoimmune condition different from classic autoimmune gastritis.

During evolution plants have evolved a multitude of adaptations to harsh environments lacking liquid water. Selectively advantageous structural adaptations include the storage of water in the parenchymatous tissues of diverse succulent plant organs, the formation of effective evaporation barriers and the minimization of water loss by rapid sealing and subsequent healing of injuries. The investigated succulent species, namely Euphorbia tirucalli, Rhipsalis baccifera ssp. mauritiana and Sansevieria cylindrica, belong to different phylogenetic lineages. They were selected based on the similar cylindrical geometry of their succulent organs and their occurrence in different ecological sites all characterized by periods of (temporary) drought. Comparative morphological and anatomical analyses were carried out on virgin control samples and on test samples after artificial mechanical damage in the longitudinal and transversal directions of the respective plant organ. Wound reactions were studied over a time span of 21 days, with various functional principles being found. Immediately after damage, mainly injury-induced physical reactions occur causing rapid self-sealing, which included: (1) tissue deformation in the wounded region resulting in wound closure and (2) discharge of mucilage/or latex. During the subsequent self-healing phase, chemical reactions and more complex biological responses dominated: (3) coagulation of latex, (4) formation of a ligno-suberized boundary layer and (5) development of a wound periderm. The results provide fundamental knowledge concerning the similarities and differences with regard to self-repairing mechanisms in succulent plant organs.

During evolution, plants evolved various reactions to wounding. Fast wound sealing and subsequent healing represent a selective advantage of particular importance for plants growing in arid habitats. An effective self-sealing function by internal deformation has been found in the succulent leaves of Delosperma cooperi. After a transversal incision, the entire leaf bends until the wound is closed. Our results indicate that the underlying sealing principle is a combination of hydraulic shrinking and swelling as the main driving forces and growth-induced mechanical pre-stresses in the tissues. Hydraulic effects were measured in terms of the relative bending angle over 55 minutes under various humidity conditions. The higher the relative air humidity, the lower the bending angle. Negative bending angles were found when a droplet of liquid water was applied to the wound. The statistical analysis revealed highly significant differences of the single main effects such as “humidity conditions in the wound region” and “time after wounding” and their interaction effect. The centripetal arrangement of five tissue layers with various thicknesses and significantly different mechanical properties might play an additional role with regard to mechanically driven effects. Injury disturbs the mechanical equilibrium, with pre-stresses leading to internal deformation until a new equilibrium is reached. In the context of self-sealing by internal deformation, the highly flexible wide-band tracheids, which form a net of vascular bundles, are regarded as paedomorphic tracheids, which are specialised to prevent cell collapse under drought stress and allow for building growth-induced mechanical pre-stresses.

The abstraction and implementation of plant movement principles into biomimetic compliant systems are of increasing interest for technical applications, e.g., in architecture, medicine, and soft robotics. Within the respective research and development approaches, advanced methods such as 4D printing or 3D-braiding pultrusion are typically used to generate proof-of-concept demonstrators at the laboratory or demonstrator scale. However, such techniques are generally time-consuming, complicated, and cost-intensive, which often impede the rapid realization of a sufficient number of demonstrators for testing or teaching. Therefore, we have produced comparable simple handcrafted compliant systems based on paper, wood, plastic foil, and/or glue as construction materials. A variety of complex plant movement principles have been transferred into these low-cost physical demonstrators, which are self-actuated by shrinking processes induced by the anisotropic hygroscopic properties of wood or paper. The developed systems have a high potential for fast, precise, and low-cost abstraction and transfer processes in biomimetic approaches and for the “hands-on understanding” of plant movements in applied university and school courses.

Background: The debate on the question whether biomimetics has a specific potential to contribute to sustainability is discussed among scientists, business leaders, politicians and those responsible for project funding. The objective of this paper is to contribute to this controversial debate by presenting the sustainability assessment of one of the most well-known and most successful biomimetic products: the façade paint Lotusan®.Results: As a first step it has been examined and verified that the façade paint Lotusan® is correctly defined as a biomimetic product. Secondly, Lotusan® has been assessed and compared to a conventional façade paint within the course of a detailed product sustainability assessment (PROSA). For purposes of comparison, the façade paint Jumbosil® was chosen as reference for a conventional paint available on the market. The benefit analysis showed that both paints fulfil equally well the requirements of functional utility. With respect to the symbolic utility, Lotusan® has a particular added aesthetic value by the preservation of the optical quality over the life cycle. Within the social analysis no substantial differences between the two paints could be found regarding the handling and disposal of the final products. Regarding the life-cycle cost, Lotusan® is the more expensive product. However, the higher investment cost for a Lotusan®-based façade painting are more than compensated by the longer life time, resulting in both reduced overall material demand and lower labour cost. In terms of the life-cycle impact assessment, it can be ascertained that substantial differences between the paints arise from the respective service life, which are presented in terms of four scenario analyses.Conclusion: In summary, the biomimetic façade paint Lotusan® has been identified as a cost-effective and at the same time resource-saving product. Based on the underlying data and assumptions it could be demonstrated that Lotusan®-based façade paintings have a comparatively low overall impact on the environment. Summarizing our results, it can be emphasized that Lotusan® is the more favourable product compared to Jumbosil® according to sustainability aspects.

Because eosinophilic esophagitis (EoE) causes dysphagia, esophageal narrowing, and strictures, it could result in low body mass index (BMI), but there are few data assessing this.To determine whether EoE is associated with decreased BMI.We conducted a prospective study at the University of North Carolina from 2009 to 2013 enrolling consecutive adults undergoing outpatient EGD. BMI and endoscopic findings were recorded. Incident cases of EoE were diagnosed per consensus guidelines. Controls had either reflux or dysphagia, but not EoE. BMI was compared between cases and controls and by endoscopic features.Of 120 EoE cases and 297 controls analyzed, the median BMI was lower in EoE cases (25 vs. 28 kg/mBMI is lower in EoE cases compared to controls, and esophageal narrowing, but not focal stricture, is associated with a lower BMI in patients with EoE. Weight loss or low BMI in a patient suspected of having EoE should raise concern for esophageal remodeling causing narrow caliber esophagus.

Lymphocytic esophagitis (LyE) is a recently described clinicopathological condition, but little is known about its features and clinical associations. The aim of this study was to characterize patients with LyE, compare them to non-LyE controls, and identify risk factors. We conducted a retrospective study of all patients ≥18 years old who underwent upper endoscopy with esophageal biopsy between January 1, 2000, and June 1, 2012. Archived pathology slides were re-reviewed, and LyE was diagnosed if there was lymphocyte-predominant esophageal inflammation with no eosinophils or granulocytes. Three non-LyE controls groups were also defined: reflux, eosinophilic esophagitis (EoE), and normal. Clinical data were extracted from electronic medical records, and LyE cases were compared to non-LyE controls. Twenty-seven adults were diagnosed with LyE, and the majority were female (63 %). The most common symptom was dysphagia (70 %). Fifty-two percentage had a prior or current diagnosis of reflux. Endoscopic findings included strictures (37 %), erosive esophagitis (33 %), rings (26 %), and hiatal hernia (26 %); 33 % of patients required dilation. After histology re-review, 78 % of LyE patients were found to have more than 20 lymphs/hpf. In comparison with the normal, reflux and EoE controls, patients with LyE tended to be nonwhite (p

Although the Venus flytrap (Dionaea muscipula) can be considered as one of the most extensively investigated carnivorous plants, knowledge is still scarce about diversity of the snap-trap motion, the functionality of snap traps under varying environmental conditions, and their opening motion. By conducting simple snap-trap closure experiments in air and under water, we present striking evidence that adult Dionaea snaps similarly fast in aerial and submersed states and, hence, is potentially able to gain nutrients from fast aquatic prey during seasonal inundation. We reveal three snapping modes of adult traps, all incorporating snap buckling, and show that millimeter-sized, much slower seedling traps do not yet incorporate such elastic instabilities. Moreover, opening kinematics of young and adult Dionaea snap traps reveal that reverse snap buckling is not performed, corroborating the assumption that growth takes place on certain trap lobe regions. Our findings are discussed in an evolutionary, biomechanical, functional–morphological and biomimetic context.