Figure 6 - uploaded by Jieliang Zhao
Content may be subject to copyright.
Environmental scanning electron microscope images of the stinger. (A) The needle-like sting, venom sac, and related glands. The stinger is activated by the muscles to penetrate the skin of the victim. (B) Barbs along the axial direction of the sting. The solid line in Figure 3(b) is the axis of the sting which is obtained by connecting the tip of the stinger and the midpoint of the stinger root. The stinger of Apis mellifera ligustica has two rows of barbs, each of which comprises about 10 barbs. The angle between the rows of barbs and the axis of the stinger shaft was around 8– 9 u , according to observations based on 10 samples. The row of barbs was found to form a right-handed helix. (C) Magnified view of the barbs. Seven barbs are marked with the notations 1–1 9 , 2–2 9 , etc. Note that the angles of the tips were 90.33 u , 89.62 u , 80.31 u , 72.13 u , 72.36 u , 59.63 u , and 46.19 u , thereby demonstrating that the barbs were relatively sharper near the tip of the stinger. (D) Magnified view of two rows of barbs. Viewed in the axial direction, the angles between the two rows of barbs were about 95 u .
Source publication
The stinger is a very small and efficient device that allows honeybees to perform two main physiological activities: repelling enemies and laying eggs for reproduction. In this study, we explored the specific characteristics of stinger penetration, where we focused on its movements and the effects of it microstructure. The stingers of Italian honey...
Context in source publication
Context 1
... s represents the region surrounded by the contour of the stinger shaft. The key point used to measure the change in configuration is defined as M ( x k , y k ) , which satisfies We define the coordinates of the key points before and after penetration as M 1 ( x k 1 , y k 1 ) and M 2 ( x k 2 , y k 2 ) , respectively. By comparing the contours of the cross-sections, we determined the amount of rotation before and after penetration. In this case, the rotation angle is h where h ~ 0 indicates that the stinger shaft does not rotate, whereas h w 0 and h v 0 indicates that the stinger shaft rotates in clockwise or anticlockwise directions, respectively. As stated above, the remaining 10 stingers were used to obtain microstructural observations with an ESEM. Particular emphasis was placed on the physical distribution and geometrical properties of the barbs on the stinger. Fig. 4 shows four cross-sections of stingers that penetrated the agar, silica gel, soft rubber, and paraffin wax substrates. The features of helical penetration are shown in the comparison chart. In particular, M A and M B are the marker points that indicate the rotation angles according to Eqs (1)–(3). We averaged the rotation angles for the subgroups A 1 , A 2 , A 3 , and A 4 which were collected from the experiments, and calculated the standard deviations of the data in different groups to test the data stability. Statistical analysis demonstrated that the data were stable with the standard deviation around 0.046 u (See Table S1 in File S1). By comparing the stinger sections before and after penetration, we found that the mean rotation angles of the 20 samples were all negative, which showed that the stingers rotated in a clockwise direction while penetrating the substrates (Fig. 5). By contrast, the rotation angle of the hair section was , 0.3 u , which demonstrated that the experimental setup did not introduce large errors, thereby validating the results. As shown in Fig. 5, the average rotation angle of the stinger shaft based on all the data was –8.364 u . The rotation angle decreased gradually as the hardness of the substrate surface increased, i.e., from the agar and silica gel, to the soft rubber and paraffin wax. The hardness of the silica gel is closest to the human skin, indicating that the stinger may approximately rotate –8.0 when it penetrates the human skin. This rotation may be attributable to the shape of the stinger and the distribution of the barbs. Understanding the underlying mechanism will help to elucidate the stinging process and related behaviors. Fig. 6 shows the microstructure of the stinger, which was obtained by ESEM. The venom sac and related glands support the stinger. The bee stinger is generally similar to a long needle and its proximal apex is covered by two lines of barbs, which subtend two angles with the stinger axis. The tetrahedron- shaped barbs decrease in size as they approach the tip of the stinger. Our results showed that the stinger shaft rotates when it is pushed into a solid substrate and its rotation angle might be affected by the hardness of the substrate. Thus, it is possible that the helical penetration might improve the puncture process, in a similar manner to the spiral flight of bullets. In addition, this specific penetration behavior increases the difficulty of sting removal, which might increase the amount of venom injected. To better understand the mechanism of the rotation of the stinger shaft, it is important to explore the dynamic performance during penetration. In particular, it is possible that the microstructure of the stinger facilitates the rotation of the stinger shaft, especially the protuberances. Fig. 7 shows a mechanistic model of stinging that considers the microstructure of the barbs. The tetrahedron model mimics the force condition of a single barb. During penetration, the contact force is not parallel to the stinger axis, therefore the torque generated by the tangential force (marked as F T in Fig. 7) can be calculated by T = rF , where r is the corresponding radius of the stinger. By focusing on the right-handed helical distribution of barbs, the angle between the line of barbs and the stinger shaft is about 8.523 u , which agrees with the average rotation angle (– 8.364 u ) shown in Fig. 5. The blunter barbs located further from the tip of stinger will expand the wound size during penetration. Therefore, the force analysis demonstrates that the helical distribution of barbs leads to the rotation of the stinger during penetration. The specific microstructure of the stinger provides new insights, which may facilitate a deeper investigation of the biological significance of stinger penetration. The main appendages of the bee stinger of Apis mellifera ligustica are derived from the segmental appendages of the 9 th and 10 th abdominal segments. The appendages of all segments are organized into segments and branches during the early stages of evolution beyond the primitive worm stage, according to the same plan, after which they have been modified in different ways for specific purposes [14,18]. According to many researchers [16], the worker bees represent the body organs required for nest maintenance, digestion, and defense [15,19–20]. Helical penetration might improve the effectiveness of attack with fewer sacrifices. The development of novel devices may also be inspired by this specific penetration mechanism [21,22]. File S1 Contains the files: Figure S1. Principle of experiment. Figure S2. Samples of the worker bees’ stings. Figure S3. The precision positioner and the substrate. Figure S4 . Location of the substrate. Figure S5. Morphology of the cross section. Figure S6. Rotation angles of the sting shaft. Table S1. The experimental results from the observation of the rotational angles. ...
Citations
... The stinger of the honeybee, shown in figure 6, is an ovipositor, which has taken an evolutive path leading to its weaponisation [31]. Several studies have been published on the morphology of this stinger and the mechanisms used to target different substrates [32][33][34], some of them proposing that the stingers serve as inspiration for human-made needles for minimally invasive surgical tasks. ...
Biomimetic research has drawn inspiration from the knowledge acquired from the diverse morphologies and specialized functions of hymenopteran ovipositors. For example, the morphology of the honeybee stinger was used to create surgical needles that reduce insertion forces, minimize tissue damage, and increase precision. Similarly, the reciprocating drilling mechanisms observed in wood-boring hymenopterans inspired the development of steerable probes for neurosurgery, offering improved control and reduced trauma during penetration. Despite these advances, the ovipositors of sawflies, which promise intricate cutting mechanisms, have remained poorly studied in biomimetics. Unlike wood-boring species, most sawflies typically cut through soft plant tissues using their saw-like ovipositors, which could inspire new designs for precise cutting and sawing devices. This review advocates the need for further research into the structure, mechanical properties and functional principles of sawfly ovipositors to fully exploit their potential in bio-inspiration. We highlight the lack of detailed mechanical studies connecting ovipositor morphology to cutting efficiency and substrate interactions. Understanding these relationships could uncover new principles for engineering applications, such as medical or industrial cutting tools.
... Moreover, the delivery rate of venom from a honeybee stinger is fast: at least 90% of venom is delivered within 20 s, and it is completely exhausted after 1 min of separation [11,12]. During penetration, the honeybee stinger undergoes a helical and clockwise rotation, which helps to improve the puncturing process [13]. Meanwhile, the honeybee stinger possesses an ultrasharp sting tip and microscopic backward-facing barbs for self-defense, providing an exquisite example of a biomicroneedle for the further design of microneedles. ...
Stingers, evolved from ovipositors, are an important defense organ for the Apidae, Vespidae, and Formicidae species. However, the molecular mechanism of stinger development remains unclear. Here, we show that the earliest time point for the appearance of stingers in Apis mellifera is at the 1-day-old worker pupal stage based on morphological observations and anatomy from the pre-pupal to adult stages. To discover the genes related to stinger development, we first comprehensively compared the stinger transcriptome at different stages and screened 1282, 186, and 166 highly expressed genes in the stingers of 1- and 5-day-old worker pupae and newly emerged worker bees (NEBs), respectively, then identified 25 DEGs involved in the early stage of stinger development. We found that Dll was a key candidate gene in the early development of A. mellifera stingers by combining analyses of the protein–protein interaction network and spatiotemporal expression patterns. An RNAi experiment showed that about 20% of individuals exhibited tip bending in the piercing parts of their stingers in the Dll-dsRNA-treated group, with the morphology presenting as side–side or front–back tip bending. This indicates that Dll plays a vital role in the early development of A. mellifera stingers. Together, our study provides insight into the molecular mechanism of Hymenoptera stinger development and an inspiration for the molecular breeding of gentle honeybee species with stinger abnormalities.
... Additionally, the slightly skewed shape of the paramere plausibly causes a screw-like movement during puncturing the female integument, akin to the mechanism observed in a honeybee's ovipositor penetration motion [58]. The ovipositor of the honeybee species features spirally arranged barbs, facilitating its helicoidal movement during the penetration process [58]. ...
... Additionally, the slightly skewed shape of the paramere plausibly causes a screw-like movement during puncturing the female integument, akin to the mechanism observed in a honeybee's ovipositor penetration motion [58]. The ovipositor of the honeybee species features spirally arranged barbs, facilitating its helicoidal movement during the penetration process [58]. ...
Cimicidae are well-known for traumatic insemination, and males pierce females with their parameres and transfer sperm through them. The shape of parameres is relatively stable in the family, but in some genera, the paramere is elongated, appearing less resistant against lateral deflection. To understand the mechanical limitations of the paramere, we studied its penetration mechanics of the common bed bug, Cimex lectularius. We examined the post-abdominal morphology, paramere geometry and material properties and conducted breaking stress experiments on the paramere under wet and dry conditions. Mechanical property gradients are present with the paramere tip as the stiffest region and the base as the most flexible one. These mechanical properties relate to the presence of Ca, Zn and Si. The basal wing-shaped structure is flexible, enabling it to interlock with the anal region during mating. The paramere is slightly twisted; the tip region is circular in cross-section, and the geometry of the rest is rather complex. In the mechanical tests, wet parameres mainly buckled, while dried parameres broke off. The level of structural failures depended on directions from which the compression forces were applied. Structural, material and mechanical strengthening mechanisms preventing the paramere from mechanical failure are discussed.
... The defining feature is that the ovipositor has been modified into a sting (Moreau, 2013). The stinger is a small, effective device that assists honey bees in two main physiological activities: defending against enemies and laying eggs for reproduction (Wu et al., 2014). Both queens and workers have a barbed stinger that is torn, with the venom sac, from the end of their abdomen when they deploy the sting into a skinned victim. ...
Natural pollen feeding induces a wide range of morphological and anatomical changes in honey bees. The worker honey bee is used to determine the effect of the natural feeding of two different types of pollen collected by the honey bee upon the development of the stinger, venom sac length, and bee venom production. This experiment was carried out in 2022 during the period from May to August in two private apiaries, where honey bee colonies are fed naturally on pollen collected from clover plants. In the present experiment, it was assessed how different plant impact the stinger and venom sac length. The results clearly showed significant differences in the stinger and venom sac parameters between the workers fed on clover plants and those fed on clover for the clover plant pollen. The present study showed that bees fed on clover pollen have longer stingers than that fed on corn pollen, also venom sac length (t=5.987; p < 0.000), and venom sac width (t=9.205; p < 0.0001) for worker bees fed on clover pollen compared to worker bees fed on corn plant pollen, the same for other parameters which showed significant differences in the Stylet length (t=7.216; p < 0.0001), and the lancets length (t=7.216; p < 0.0001), barbs lancet length (t=9.205; p < 0.0001. These results indicated that the development of the stinger, venom sac parameters, and quantity of collected bee venom is extremely sensitive to the type of nutrients.
... The penetration mechanism of honeybee stingers has been extensively examined in various studies. [13][14][15] The stinger's barbs reduce the insertion force while increasing the extraction force, primarily due to the small back barb angle ( ). In Figure 1(a), it can be observed that honeybee barbs have a large front barb angle greater than 90° and a small back barb angle less than 90°. ...
Accurate needle insertion is critical during minimally invasive procedures such as biopsy, drug delivery, tumor ablation, and brachytherapy. Various factors affect needle position precision: insertion force, tissue deformation, tissue damage, image-guided tools, surgeons' technique, and obstacles on the insertion path. This paper reviews the current state of needle designs for percutaneous procedures, including mechanics of needle-tissue interactions and steering techniques. Bioinspired needles and coated needles focus on the mechanics of needle-tissue interactions, leading to reductions in insertion-extraction force, tissue deformation, and tissue damage. Different steering techniques: wasp's ovipositor-inspired, pre-curved, tendon-actuated, shape memory alloy (SMA)-actuated are developed to improve maximum curvature, deflection, and targeting accuracy. Quantified results as proof of needle performance advancements are presented if applicable.
... The extraction force was enhanced because the barbs mechanically interlocked in the tissue. The insertion mechanism of the honeybee stinger has also been studied by Wu et al. [14], and they concluded that the stinger's barbs minimize the penetration force and enable the stinger to revolve when it penetrates the human tissue. ...
Minimally invasive biopsy needles are frequently inserted into the desired body regions while performing the bone marrow biopsy (BMB) procedure. The key problem with needle insertion in tissues is that the insertion force damages the tissue and deviates the needle path, leading the needle to miss the desired target and reducing biopsy sample integrity. To address these shortcomings, the present work developed a unique bioinspired barbed biopsy needle design that reduces insertion/extraction forces and needle deflection. This study established several design parameters, including barb geometry and shape (viz., the height of barb, barbed front angle, barbed back angle, and length of portion containing barbs), and examined the impact of these factors on insertion/extraction force and deflection. A Lagrangian surface-based non-linear finite element (FE) approach has been used to numerically simulate the BMB procedure on a three-dimensional (3D) multilayered heterogeneous model of the human iliac crest. The proposed honeybee stinger-inspired needle design has been found to reduce both insertion and extraction forces because of the decreased frictional surface of the biopsy needle.
... Various other techniques have been application of micro-needle array [9][10][11] and transdermal patches [12] with minimal invasion to the skin and tissue. Taking inspiration from cutting and puncturing devices in nature, like proboscis of mosquito [13,14], stinger of bee [15], quills on the dorsal surface of porcupine [16], or dogfish's teeth [17], hierarchical structures of the needle have also has been explored [18]. Design of a multiple tip needle is one such attempt, where overlap of stress fields of closely spaced needle tips results in enhanced stress concentration ahead of the needle tip [18,19] which diminishes the resistance to puncture. ...
A hypodermic syringe needle, undergoing axial vibration, can puncture a soft solid at a load smaller than that is required when it is driven at a uniform axial velocity. While this decrease in insertion load is a function of dynamical features of the insertion process, geometric parameters and elastic modulus of the solid, the optimal range of values at which the effect of vibration becomes apparent and in fact maximize is not yet known. In this report, we have carried out systematic displacement-controlled puncturing of a soft yet brittle hydrogel material using syringe needles of range of diameter, at varying insertion speed, while subjecting it also to longitudinal vibration at different frequency and amplitude. After analyzing the experimental data, we have identified the relevant dimensionless quantities that can help identify the range of parameter values for which decrease in the insertion load of the needle maximizes. Our phenomenological model shows that the average axial speed of insertion of the needle and amplitude of vibration of the needle, both affect the percentage decrease in the puncturing load quite prominently. However, within the range of vibration frequency examined, its effect was not found to be significant.
... The insertion speed also affects the deflection, decreasing needle bending [21]. In order to encourage more accurate needle insertion, several research studies to replicate insect stingers are now ongoing using penetration techniques like honeybee [22][23][24] and mosquito [25]. Since insect stingers have developed and grown skilled at penetrating human tissue using various dynamic and mechanical insertion strategies, they show potential for improving needle design [26]. ...
... Wu et al. [23] and Ling et al. [28] conducted independent studies on honeybee stingers and their barbs. Ling et al. [28] concluded from their study that the design of the stinger allows for a comparatively painless penetration into the human skin. ...
... A honeybee stinger influenced our unique bioinspired needle's geometry. The strong barbs on a honeybee stinger reduce the insertion force [23,28]. This distinctive quality motivated us to develop a unique bioinspired needle shape that could offer lower penetration force than traditional needles. ...
Bone marrow biopsy (BMB) needles are frequently used in medical procedures, including extracting biological tissue to identify specific lesions or abnormalities discovered during a medical examination or a radiological scan. The forces applied by the needle during the cutting operation significantly impact the sample quality. Excessive needle insertion force and possible deflection might cause tissue damage, compromising the integrity of the biopsy specimen. The present study aims at proposing a revolutionary bioinspired needle design that will be utilized during the BMB procedure. A non-linear finite element method (FEM) has been used to analyze the insertion/ extraction mechanisms of the honeybee-inspired biopsy needle with barbs into/from the human skin-bone domain (i.e., iliac crest model). It can be seen from the results of the FEM analysis that stresses are concentrated around the bioinspired biopsy needle tip and barbs during the needle insertion process. Also, these needles reduce the insertion force and reduce the tip deflection. The insertion force in the current study has been reduced by 8.6% for bone tissue and 22.66% for skin tissue layers. Similarly, the extraction force has been reduced by an average of 57.54%. Additionally, it has been observed that the needle-tip deflection got reduced from 10.44 mm for a plain bevel needle to 6.3 mm for a barbed biopsy bevel needle. According to the research findings, the proposed bioinspired barbed biopsy needle design could be utilized to create and produce novel biopsy needles for successful and minimally invasive piercing operations.
... In nature, the shape of puncturing systems is highly diverse and closely connected with their function. 11 A straight offensive tool such as the harpoon of the cone snail, 37 the bee stinger, 38 or the mosquito proboscis 39 may be used to maximize penetration depth, 11 whereas highly curved devices like crustaceans claws 40 or spider fangs 41 should enable puncture along different trajectories and facilitate prey retention. 35,37 The unusual form of the spike, featuring both curved and straight zones, may be a trade-off between large penetration depth and prey grabbing. ...
Spearing mantis shrimps are aggressive crustaceans using specialized appendages with sharp spikes to capture fishes with fast movement. Each spike is a biological tool that has to combine high toughness, as required by the initial impact with the victim, with high stiffness and strength, to ensure sufficient penetration while avoid breaking. We performed a multimodal analysis to uncover the design strategies of this harpoon based on chitin. We found that the spike is a slightly hooked hollow beam with the outer surface decorated by serrations and grooves to enhance cutting and interlocking. The cuticle of the spike resembles a multilayer composite: An outer heavily mineralized, stiff, and hard region (with average indentation modulus and hardness of 68 and 3 GPa), providing high resistance to contact stresses, is combined with a less mineralized region, which occupies a large fraction of the cuticle (up to 50%) and features parallel fibers oriented longitudinally, enhancing stiffness and strength. A central finding of our work is the presence of a tiny interphase (less than 10 μm in width) based on helical fibers and showing a spatial modulation in mechanical properties, which has the critical task to integrate the stiff but brittle outer layer with the more compliant highly anisotropic parallel‐fiber region. We highlighted the remarkable ability of this helicoidal region to stop nanoindentation‐induced cracks. Using three‐dimensional multimaterial printing to prototype spike‐inspired composites, we showed how the observed construction principles can not only hamper damage propagation between highly dissimilar layers (resulting in composites with the helical interphase absorbing 50% more energy than without it) but can also enhance resistance to puncture (25% increase in the force required to penetrate the composites with a blunt tool). Such findings may provide guidelines to design lightweight harpoons relying on environmentally friendly and recyclable building blocks.
Key Points
–The heavily mineralized biological appendages of the mantis shrimp are a constant source of inspiration for developing new engineering materials.
–We use characterization methods of material science to investigate a biological harpoon based on chitin.
–Several morphological, compositional, microstructural, and biomechanical features are highlighted, allowing the spikes of the mantis shrimp to be remarkable lightweight, tough, and stiff harpoons.
... Various kinds of penetrating organs for attacking and defence, are evolved in many arthropods such as honeybees [1][2][3][4][5], wasps [1,2,[5][6][7], scorpions [8] and mosquitoes [9,10], to achieve different mechanical and biological functionalities. As summarized by Shergold and Fleck [11], the process of penetration by the tip into soft tissue is generally decomposed into three stages. ...
... Until now, relatively comprehensive studies on the stingers and penetrating mechanisms of arthropods have been carried out, such as stinger surface structure [4,5], local mechanical properties [1], puncture force measurement [2,3], penetrating process capturing [3,5] and penetrating simulation [2]. Das et al. [1] using nanoindentation found that both honeybee and wasp stingers have graded mechanical properties decreasing from the base along their longitudinal axis. ...
... Das et al. [1] using nanoindentation found that both honeybee and wasp stingers have graded mechanical properties decreasing from the base along their longitudinal axis. Most likely due to the microstructured barbs on the stinger surface [4], the stinger puncture force is greatly larger than its pull-out force by the finite element method (FEM) [2,3,5]. However, whether the modulus distribution (i.e., cuticle sclerotization) of the honeybee stinger agrees well with the graded mechanical properties measured by Das et al. [1] as well as how the modulus distribution affects the stinger penetration behavior are still unclear. ...
The honeybee stinger, as an important organ for self-defense and reproduction, have evolved specific macroscopic morphologies and microscopic structures. Here, we investigated the surface and cross-sectional structures and material composition of the cuticle in the stingers of worker honeybees (Apis mellifera). Except the stinger bulb, the cuticle sclerotization of the stinger is found to be uniformly distributed along its longitudinal axis, i.e., uniform modulus distribution. Based on this, we developed a two-dimensional (2D) model to explore the influence of various modulus distributions of the stinger on its penetration behavior in vertical and oblique penetrations using the finite element method (FEM). It is found that compared with the stinger models with the modulus-gradient distribution (5 GPa at the stinger tip to 15 GPa at its base) and negative modulus-gradient distribution (15 GPa at the tip to 5 GPa at base), the model with uniform modulus distribution (10 GPa) can be more easily inserted into the skin with less maximal penetration force in no matter vertical or oblique penetrations. Therefore, the uniform modulus distribution along the axis as revealed by our confocal laser scanning microscopy is beneficial for the honeybee stinger to achieve its self-defense with fast penetration. This study significantly enriches the understanding of the stinger functionality and inspires us with new avenues for bioinspired microneedles in modern engineering.
