Adhesive Pads Research Articles

Sharp claws beneath our feet – the diversity of tarsal attachment devices of oribatid mites (Acari, Chelicerata, excluding Astigmata) – a review

ABSTRACT The majority of animals possess claws on their legs and they are mainly used for keeping attached to the substrate. Recent studies on claw shapes and function suggest that claws are not just simple attachment devices but highly specialized morphological traits bearing information about lifestyle, ecology and evolution. In that respect, knowledge about claws is extremely scarce, especially in highly diverse groups, as for example the oribatid mites, with more than 11000 named species occurring in every environment all over the world. This review summarizes all information about claws and relevant aspects for this large group of arthropods. There is a huge variety of ambulacral claw morphologies present in oribatid mites and this diversity does not follow a strict phylogenetic or systematic pattern. Lifestyle and ecology apparently play an important role in shaping claw morphologies. Intertidal oribatid mites are mostly characterized by having single large tarsal claws to withstand tidal flooding, a similar tendency can be found in terrestrial limnic species where monodactylous species prevail. Additionally, fresh-water Oribatida often show scaliform and barbed distal tarsal setae which cooperate with the claws helping the mites to stick to water plants. Claws of arboreal mites are often equipped with adhesive pads “pulvilli” allowing them to walk on smooth plant surfaces. Suction pads are also found in a few mites showing epilithic lifestyles and in mites being able to perform sudden evasive jumps. Claws of phoretic oribatid mites show in most cases no apparent adaptations but certain groups are equipped with highly modified claws allowing them to attach to specific structures of their hosts. Finally, this review gives an overview of all claw morphologies present in each larger phylogenetic oribatid mite group.

Alternate morphological pathways involved in climbing ability in ten Neotropical anuran species

Abstract Convergent evolution has been shown to be a prominent feature of anuran evolutionary history. Studying the morphological pathways involved in the evolution of a convergent character allows us to test whether deterministic or contingent forces drive the evolution of characters. Here, we have assessed the morphological pathways associated with arboreal habits in species of six families of anurans (Hylidae, Eleutherodactylidae, Strabomantidae, Centrolenidae, Bufonidae and Hemiphractidae) through a comparative analysis of 19 phenotypic characters related to climbing ability. All species showed differences in the assessed characters, exhibiting variations in the distribution of their states and different ranges in all limb lengths. These variations implied a wide distribution across the morphospace as defined by a non-metric multidimensional scaling analysis (NMDS), with Rhinella paraguas (Bufonidae) being the most distinctive species, presenting unique characters such as the absence of intercalary elements, adhesive pads, subarticular tubercles and interphalangealis muscles of the hands. Our findings demonstrate that the morphological mechanisms involved in climbing ability of the ten species are different, suggesting distinct morphological pathways. Consequently, we advocate that historical contingency has an essential role in the evolution of arboreal habits among the species studied.

Skeletal muscle oxidative adaptations following localized heat therapy

Repeated heat treatment has been shown to induce oxidative adaptations in cell cultures and rodents, but similar work within human models is scarce. This study investigated the effects of 6 weeks of localized heat therapy on near-infrared spectroscopy-(NIRS) derived indices of muscle oxidative and microvascular function. Twelve physically active participants (8 males and 4 females, age: 34.9 ± 5.9 years, stature: 175 ± 7 cm, body mass: 76.7 ± 13.3 kg) undertook a 6-week intervention, where adhesive heat pads were applied for 8 h/day, 5 days/week, on one calf of each participant, while the contralateral leg acted as control. Prior to and following the intervention, the microvascular function was assessed using NIRS-based methods, where 5 min of popliteal artery occlusion was applied, and the reperfusion (i.e., re-saturation rate, re-saturation amplitude, and hyperemic response) was monitored for 2 min upon release. Participants also performed a 1-min isometric contraction of the plantar flexors (30% maximal voluntary contraction), following which a further 2 min interval was undertaken for the assessment of recovery kinetics. A 20-min time interval was allowed before the assessment protocol was repeated on the contralateral leg. Repeated localized heating of the gastrocnemius did not influence any of the NIRS-derive indices of microvascular or oxidative function (p > 0.05) following 6 weeks of treatment. Our findings indicate that localized heating via the use of adhesive heat pads may not be a potent stimulus for muscle adaptations in physically active humans.

Defibrillation effectiveness and safety of the shock waveform used in a contemporary wearable cardioverter defibrillator: Results from animal and human studies.

The wearable cardioverter defibrillator (WCD) is used to protect patients at risk for sudden cardiac arrest. We examined defibrillation efficacy and safety of a biphasic truncated exponential waveform designed for use in a contemporary WCD in three animal studies and a human study. Animal (swine) studies: #1: Efficacy comparison of a 170J BTE waveform (SHOCK A) to a 150J BTE waveform (SHOCK B) that approximates another commercially available waveform. Primary endpoint first shock success rate. #2: Efficacy comparison of the two waveforms at attenuated charge voltages in swine at three prespecified impedances. Primary endpoint first shock success rate. #3: Safety comparison of SHOCK A and SHOCK B in swine. Primary endpoint cardiac biomarker level changes baseline to 6 and 24 hours post-shock. Human Study: Efficacy comparison of SHOCK A to prespecified goal and safety evaluation. Primary endpoint cumulative first and second shock success rate. Safety endpoint adverse events. Animal Studies #1: 120 VF episodes in six swine. First shock success rates for SHOCK A and SHOCK B were 100%; SHOCK A non-inferior to SHOCK B (entire 95% CI of rate difference above -10% margin, p < .001). #2: 2,160 VF episodes in thirty-six swine. Attenuated SHOCK A was non-inferior to attenuated SHOCK B at each impedance (entire 95% CI of rate difference above -10% margin, p < .001). #3: Ten swine, five shocked five times each with SHOCK A, five shocked five times each with SHOCK B. No significant difference in troponin I (p = 0.658) or creatine phosphokinase (p = 0.855) changes from baseline between SHOCK A and SHOCK B. Human Study: Thirteen patients, 100% VF conversion rate. Mild skin irritation from adhesive defibrillation pads in three patients. The BTE waveform effectively and safely terminated induced VF in swine and a small sample in humans. Human study clinical trial registration: URL: https://clinicaltrials.gov; Unique identifier: NCT04132466.

Adaptive behaviors of Drosophila larvae on slippery surfaces

Friction is ubiquitous but an essential force for insects during locomotion. Insects use dedicated bio-mechanical systems such as adhesive pads to modulate the intensity of friction, providing a stable grip with touching substrates for locomotion. However, how to uncover behavioral adaptation and regulatory neural circuits of friction modification is still largely understood. In this study, we devised a novel behavior paradigm to investigate adaptive behavioral alternation of Drosophila larvae under low-friction surfaces. We found a tail looseness phenotype similar to slipping behavior in humans, as a primary indicator to assess the degree of slipping. We found a gradual reduction on slipping level in wild-type larvae after successive larval crawling, coupled with incremental tail contraction, displacement, and speed acceleration. Meanwhile, we also found a strong correlation between tail looseness index and length of contraction, suggesting that lengthening tail contraction may contribute to enlarging the contact area with the tube. Moreover, we found a delayed adaptation in rut mutant larvae, inferring that neural plasticity may participate in slipping adaptation. In conclusion, our paradigm can be easily and reliably replicated, providing a feasible pathway to uncover the behavioral principle and neural mechanism of acclimation of Drosophila larvae to low-friction conditions.

Ultrastructural observations suggest that lipid material of lizard digital pads derives from degenerating cells in the inter‐scale region

AbstractUltrastructural observations suggest that lipid material of lizard digital pads derives from degenerating cells in the inter‐scale region. Acta Zoologica (Stockholm). Production of epidermal lipids in lizards occurs in mesos‐ and alpha‐layers, including those present in gecko adhesive pads. Lipid material is present over the setae and spatulae of adhesive pads where adhesion takes place. Lipids are hypothesized to influence the process of adhesion keeping hydrophobic the spatula that contacts the substrate. The origin of lipids in pad lamellae that are lost as footsteps during gecko movements is unknown. To maintain setae lipid‐coated requires a large and continuous supply of lipids and the most likely source is an epidermal region rich in lipids. Ultrastructural observations show that lipid material is released from sloughed mesos and alpha‐cells in the inter‐scale region of the lamellae. It is hypothesized that lipids passively move from the hinge region and reach the outer lamella surface. Lipids may also derive from frictional damage of the thin alpha‐cells located in the hinge regions during pad extension for climbing or moving on the substrate. The discharged lipid material is likely pushed out from the hinge region by progressive accumulation of secreted material. The present hypothesis presents a simple model illustrating lipid movement from inter‐scale regions that coat the setae, contributing to the indicated influence of lipids on spatula adhesion.

Controllable adhesion behavior in underwater environments.

Microstructure adhesive pads can effectively manipulate objects in underwater environments. Current adhesive pads can achieve adhesion and separation with rigid substrates underwater; however, challenges remain in the control of adhesion and detachment of flexible materials. Additionally, underwater object manipulation necessitates considerable pre-pressure and is sensitive to water temperature fluctuations, potentially causing object damage and complicating adhesion and detachment processes. Thus, we present a novel, controllable adhesive pad inspired by the functional attributes of microwedge adhesive pads, combined with a mussel-inspired copolymer (MAPMC). In the context of underwater applications for flexible materials, the use of a microstructure adhesion pad with microwedge characteristics (MAPMCs) is a proficient approach to adhesion and detachment operations. This innovative method relies on the precise manipulation of the microwedge structure's collapse and recovery during its operation, which serves as the foundation for its efficacy in such environments. MAPMCs exhibit self-recovering elasticity, water flow interaction, and tunable underwater adhesion and detachment. Numerical simulations elucidate the synergistic effects of MAPMCs, highlighting the advantages of the microwedge structure for controllable, non-damaging adhesion and separation processes. The integration of MAPMCs into a gripping mechanism allows for the handling of diverse objects in underwater environments. Furthermore, by merging MAPMCs and a gripper within a linked system, our approach enables automatic, non-damaging adhesion, manipulation, and release of a soft jellyfish model. The experimental results indicate the potential applicability of MACMPs in underwater operations.

DESENVOLVIMENTO DE TECNOLOGIA EDUCACIONAL PARA MANEJO DO MARCA-PASSO TRANSCUTÂNEO EM IDOSOS NO ATENDIMENTO PRÉ-HOSPITALAR MÓVEL

ABSTRACT Objective: to develop educational technology for nurses on transcutaneous pacemaker management in older adults undergoing mobile pre-hospital assistance. Method: a methodological study developed with the Advanced Support Units of the Mobile Urgency Care Service of the 2nd Metropolitan Health Region of Paraná, Brazil, in three phases: 1) Pre-production - preparation of the video script; 2) Production - script validation by expert judges, storyboard development, voiceover recording and selection of images; and 3) Post-production - evaluation of the video by expert judges and diffusion. 51 specialist judge nurses took part in validation of the script; and 47 of them assessed the video. The data were collected between April and May 2022 using instruments with a Likert scale, via Google Forms. Descriptive statistics was applied for data analysis and a Content Validity Index of at least 0.78 was considered. Results: the judges suggested less technical language, inclusion of a scene and a correction referring to the positioning of the transcutaneous pacemaker adhesive pads. A 2D video lasting 8 minutes and 30 seconds was produced, which addressed actions and care measures in managing pacemakers in older adults. The following items were considered adequate: language, images, voiceover, duration, guidelines proposed and memorization of the messages (CVI=1.0). Conclusion: the educational technology developed was considered validated for nurses regarding the transcutaneous pacemaker management in older adults. The educational video can support decision-making in favor of patient and team safety and treatment efficacy, in order to qualify the assistance provided.

Development of a General-purpose Gripper with Selectable Gripping Method by Jamming Transfer and Adhesion

In recent years, the use of robots has been considered due to the labor shortage. In this situation, the utilization of soft robot grippers that can grasp various objects is expected in the industrial world. The purpose of this study is to develop a soft robotic hand with an adhesion pad attached to a jamming gripper to enable grasping of flat and complex shaped objects. The gripper we have developed can be switched between a jamming gripper and a suction pad by switch control. This makes it possible to perform grasping according to the object. We applied a load to the gripper and conducted a gripping experiment on a complex-shaped object or a flat object. As a result, the gripping success rate of the jamming gripper increased as the applied load increased, and a stable gripping success rate was obtained on the adhesion side. Therefore, it can be seen that the gripper in this study satisfies the sufficient performance.

Biomechanically-Consistent Skin Stretch as an Intuitive Mechanism for Sensory Feedback: A Preliminary Investigation in the Lower Limb.

The proprioceptive loss accompanied by lower limb amputation can impair function and mobility. We explore a simple, mechanical skin-stretch array configured to generate superficial tissue behaviour that might occur with movement about an intact joint. Four adhesive pads attached around the circumference of the lower leg were connected via cords to a remote "foot" mounted on a ball joint attached to the underside of a fracture boot, such that "foot" reorientation would result in skin stretch. In two discrimination experiments performed with and without the connection, with no view of the mechanism, and with minimal training, unimpaired adults (i) estimated foot orientation following passive foot rotations (eight directions), either with or without contact between the lower leg and boot, and (ii) actively lowered the "foot" to estimate slope orientation (four directions). In (i), 56-60% of responses (depending on contact condition) were correct and 88-94% were either correct or one of the two adjacent choices. In (ii), 56% of responses were correct. In contrast, without the connection, participants performed near or no different to chance. A biomechanically-consistent skin stretch array may be an intuitive means to convey proprioceptive information from an artificial or poorly innervated joint.

Bio-inspired dry adhesive pads using multi-walled carbon nanotube/polydimethylsiloxane composites for efficient wafer transfer robot arms in smart factories

We report the bio-inspired dry adhesive pads (BDAPs) with various shapes and contact areas optimized for various robot arm movements. Moreover, MWCNT/PDMS composite-based BDAP (c-BDAP) has shown superior heat resistance and electrical conductivity.

The Periodic Replacement of Adhesive Setae in Pad Lamellae of Climbing Lizards Is Driven by Patterns of Corneous Layer Growth

The adhesive digital pads in some gecko and anoline lizards are continuously utilized for movements on vertical surfaces that may determine wear and a decrease of adhesion efficiency. The pads are formed by lamellae bearing adhesive setae that are worn out following frequent usage and are replaced by new inner setae that maintain an efficient adhesion. Whether the extensive usage of adhesive setae determines a higher shedding frequency in the digital pads with respect to other body regions remains unknown. Setae replacement has been analyzed in embryos and adult lizards using autoradiography and 5BrdU-immunohistochemistry. The observation strongly suggests that during development and epidermal renewal in adult lamellae, there is a shifting of the outer setae toward the apex of the lamella. This movement is likely derived from the continuous addition of proteins in the beta- and alpha-layers sustaining the outer setae while the inner setae are forming. Ultrastructural and in situ hybridization studies indicate that the thin outer beta- and alpha-layers still contain mRNAs and ribosomes that may contribute to the continuous production of corneous beta proteins (CBPs) and keratins for the growth of the free margin at the apex of the lamella. This process determines the apical shifting and release of the old setae, while the new inner setae formed underneath becomes the new outer setae.

손 기능 회복을 위한 신경인지재활치료 도구개발 버전 2

The hand is the external brain. The hands are motor organs that carry out the commands given by the brain, and they are the sensory organs that provide the most information to the brain. When you move your hands or accept changes in the outside world with your hands, your brain is activated. Using your hands is an act that stimulates the highest levels of mental functioning. The purpose of this research and development is to contribute to the efficient and effective recovery of hand function through the continuous development of neurocognitive rehabilitation therapy training tools.&#x0D; Innovative improvements to the function of the hand function recovery training tool version I. The fixing part is equipped with silicone adhesive pads for easy movement and fixation. The height of the support is 75 mm, and the maximum height of the training tool is 200 mm. The height was considered so that the head could be relaxed and trained to restore hand function. The rotating part is very creative. 180° turns are possible on the forehead surface and 270° turns on the sagittal surface. In addition, the entire rotating part has been developed to be able to rotate 360° degrees.&#x0D; Innovative improvements in neurocognitive rehabilitation training tools for hand function training have enabled efficient and effective training. It is hoped that it will be actively used in clinical practice and contribute to the recovery of hand function in patients.

Microtemplated Electrowetting for Fabrication of Shape‐Controllable Microdomes in Extruded Microsucker Arrays toward Octopus‐Inspired Dry/Wet Adhesion

AbstractInspired by the prominent adhesion ability of octopus suckers, many dry/wet adhesives with specific micro‐structure have been fabricated for applications in smart robots, manipulators, and medical treatments. However, the reported octopus‐inspired adhesive patches are either suction‐assistant without tight‐sealing, or suction‐sealed but inefficient under both dry/wet environments. Here, a microtemplated electrowetting method is developed for the fabrication of reversible dry/wet adhesive pads consisting of extruded microsuckers with suction‐enhanced microdomes and sealing‐ring tips. The mechanism toward the morphology regulation of microdomes illustrates the uneven electrohydrodynamic force on the liquid–air interface that changes the liquid meniscus and achieves the precise regulation of the microdomes curvature ratio (from 0.45 to 0.74). The tip spacing can be controlled (from 0 to 50 µm) by using different templates. Theoretical and experimental insights into the mechanism of the microdomes morphology and the tip spacing on adhesion are discussed. With optimized microdomes and maximized sealing‐tips, this adhesive patch generates strong and repeatable adhesion on a silicon wafer in both air (≈ 86 kPa) and underwater (≈ 61 kPa) environments. Besides, considerable adhesion to the rough surfaces are also revealed. Its adhesion ability is demonstrated with stable transportation of various objects under air/underwater environments, providing a potential application in cross‐media operation.

Mechanisms of detachment in fibrillar adhesive systems

Several creatures can climb on smooth surfaces with the help of hairy adhesive pads on their legs. A rapid change from strong attachment to effortless detachment of the leg is enabled by the asymmetric geometry of the tarsal hairs. In this study, we propose mechanisms by which the hairy pad can be easily detached, even when the hairs possess no asymmetry. Here, we examine the possible function of the tibia-tarsus leg joint and the claws. Based on a spring-based model, we consider three modes of detachment: vertically pulling the pad while maintaining either a (1) fixed or a (2) free joint, or by (3) flexing the pad about the claw. We show that in all cases, the adhesion force can be significantly reduced due to elastic forces when the hairs deform non-uniformly across the array. Our proposed model illustrates the design advantage of such fibrillar adhesive systems, that not only provide strong adhesion, but also allow easy detachment, making them suitable as organs for fast locomotion and reliable hold. The presented approaches can be potentially used to switch the adhesion state in bio-inspired fibrillar adhesives, by incorporating artificial joints and claws into their design, without the need of asymmetric or stimuli-responsive fibrillar structures.

Effects of Flexural Rigidity on Soft Actuators via Adhering to Large Cylinders

This study proposes a soft pneumatic actuator with adhesion (SPAA) consisting of a top fluidic-driven elastic actuator and four bottom adhesive pads for adhering to large cylinders. Finite element models were developed to investigate the bending properties under positive air pressure and the effect of “rib” height on the flexural rigidity of the SPAA. A synchronous testing platform for the adhesive contact state and mechanics was developed, and the bending curvature and flexural rigidity of the SPAA were experimentally measured relative to the pressure and “rib” height, respectively, including the adhesion performance of the SPAA with different rigidities on large cylinders. The obtained results indicate that the SPAA can continuously bend with controllable curvature under positive air pressure and can actively envelop a wide range of cylinders of different curvatures. The increase in the “rib” height from 4 to 8 mm increases the flexural rigidity of the SPAA by approximately 230%, contributing to an average increase of 54% in the adhesion performance of the SPAA adhering to large cylinders. The adhesion performance increases more significantly with an increase in the flexural rigidity at a smaller peeling angle. SPAA has a better adhesion performance on large cylinders than most existing soft adhesive actuators, implying that is more stable and less affected by the curvature of cylinders. To address the low contact ratio of the SPAA during adhesion, the optimization designs of the rigid–flexible coupling hierarchical and differentiated AP structures were proposed to increase the contact ratio to more than 80% in the simulation. In conclusion, this study improved the adhesion performance of soft adhesive actuators on large cylinders and extended the application scope of adhesion technology. SPAA is a basic adhesive unit with a universal structure and large aspect ratio similar to that of the human finger. According to working conditions requirements, SPAAs can be assembled to a multi-finger flexible adhesive gripper with excellent maneuverability.

Electron microscopic analysis in the gecko Lygodactylus reveals variations in micro-ornamentation and sensory organs distribution in the epidermis that indicate regional functions.

Possible pattern variations of micro-ornamentation in different areas of the skin in the gecko Lygodactylus have been analyzed by scanning and transmission electron microscopy. A map of micro-ornamentation present in various areas of the skin has been obtained. Differences in micro-ornamentation pattern and sensory organ distribution were detected. The "spinulated pattern" consists of shorter spinulae in dorsal versus ventral scales, and spinules are shorter in inner scale surface and hinge regions with respect to the outer scale surface. The spines derive from the accumulation of struts of corneous material mainly composed of corneous beta proteins (CBPs, formerly indicated as beta-keratins) that merge into pointed micro-ornamentation. The 3D-accumulation of CBPs within Oberhautchen cells can vary in some regions of different scales during Oberhautchen-beta cell differentiation, perhaps also under physical tensile forces derived from continuous scale growth. Three other main patterns of micro-ornamentation were detected and indicated as "corneous belts," "corneous dendritic ramification," and "serpentine-pit and groove." These variations from the typical spinulated pattern present in gecko epidermis are interpreted as transitional regions where the accumulation of corneous material in Oberhautchen cells that merges with underlying beta-cells gives rise to nonspinulated surfaces. Spinulated sensory organs with bristles and lenticular-shaped or knob-like tactile corpuscles are more numerous in ventral scales of the tail tip close to adhesive pads and near the digital pads. These regions are likely those most involved in the fine control of movements and response to vibrational stimuli derived from air and objects movements, including potential preys or predators.

Enhanced photocontrollable dynamic adhesion of nematic elastomers on rough surfaces

Polymers with switchable adhesion properties are important for efficient catch-and-release processes in robotic hand applications and handgrips with on-demand adhesion control. However, counter objects often have a rough surface topography, which requires a dynamic adhesion system that balances adhesion and detachment performances. Here, we demonstrate that a photosensitive nematic main-chain liquid crystal elastomer (LCE) has suitable photoswitchable adhesion properties on surfaces with micrometer-scale roughness, resulting in a large adhesion change. The nematic LCE exhibits the so-called “soft elasticity,” wherein it can deform at a certain strain without increasing the elastic energy. Such deformation can be maintained owing to arrested relaxation, enabling the LCE to deform along with a rough surface upon light pressure. This increases the contact area and consequently enhances adhesion ability. On the other hand, the LCE exhibits rubber elasticity after proper light irradiation owing to a phase transition from the nematic to the isotropic phase. As rubber elasticity limits deformation, the contact area on the rough surface, and thus the adhesion, is greatly reduced. This LCE with photoswitchable elasticity has great merit as a dynamic adhesive pad for treating objects with rough surfaces, which may expand the versatility of stimuli-responsive adhesive systems.

Gripping performance in the stick insect Sungaya inexpectata in dependence on the pretarsal architecture

Insect attachment devices and capabilities have been subject to research efforts for decades, and even though during that time considerable progress has been made, numerous questions remain. Different types of attachment devices are known, alongside most of their working principles, however, some details have yet to be understood. For instance, it is not clear why insects for the most part developed pairs of claws, instead of either three or a single one. In this paper, we investigated the gripping forces generated by the stick insect Sungaya inexpectata, in dependence on the number of available claws. The gripping force experiments were carried out on multiple, standardized substrates of known roughness, and conducted in directions both perpendicular and parallel to the substrate. This was repeated two times: first with a single claw being amputated from each of the animals’ legs, then with both claws removed, prior to the measurement. The adhesive pads (arolia) and frictional pads (euplantulae) remained intact. It was discovered that the removal of claws had a detractive effect on the gripping forces in both directions, and on all substrates. Notably, this also included the control of smooth surfaces on which the claws were unable to find any asperities to grip on. The results show that there is a direct connection between the adhesive performance of the distal adhesive pad (arolium) and the presence of intact claws. These observations show collective effects between different attachment devices that work in concert during locomotion, and grant insight into why most insects possess two claws.

Geometric Morphometrics Reveal Shape Differences in the Toes of Urban Lizards.

SynopsisUrbanization, despite its destructive effects on natural habitats, offers species an opportunity to colonize novel niches. Previous research found that urban Anolis lizards in Puerto Rico had increased adhesive toepad area and more ventral toepad scales, traits that are likely adaptive and genetically based. We further investigated these phenotypic changes using geometric morphometrics to measure differences in toe shape, toepad shape, and lamellar morphology. Our results indicate that the increased toepad area of urban Anolis cristatellus lizards in Puerto Rico is not simply an isometric increase in toe size. Toes of urban populations exhibit multiple disproportional changes compared to forest lizards, with a larger proportion of the toe length covered in adhesive toepad. In addition, the toepads of urban lizards increase more in length than width. Lastly, lizards in urban populations exhibit both increased number of lamellae as well as increased spacing between individual lamellae. We also observed regional variation, with urban specimens having significantly more disparity, suggesting similar processes of urban adaptation are likely happening in parallel across the island, yet with region-specific idiosyncrasies, possibly generating more variation in toepad morphology across urban specimens as compared to forest specimens. Considering the use of geometric morphometrics, we found that specimen preparation, specifically how flat and straight toes are during imaging, to be an important factor affecting our data, more so than specimen size or any other meaningful morphological variation. In addition, we found that landmark and semilandmark data can be used to directly estimate toepad area, offering the opportunity to streamline future studies. In conclusion, our results highlight the value of considering toepad morphology in more detail beyond adhesive pad area or number of lamellae. Geometric morphometrics tools may be employed to elucidate subtle differences in shape to better allow researchers to connect changes in morphology to ecology and adhesive performance.