Insect attachment on waxy plant surfaces: the effect of pad contamination by different waxes

• Elena V. Gorb and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2024, 15, 385–395, doi:10.3762/bjnano.15.35

• contamination of insect adhesive pads with three-dimensional epicuticular waxes of different plant species contributes to the reduction of insect attachment. We measured traction forces of tethered Chrysolina fastuosa male beetles having hairy adhesive pads on nine wax-bearing plant surfaces differing in both

• tested insects showed a strong reduction of the maximum traction force on all waxy plant surfaces compared to the reference experiment on glass (gl1). After beetles have walked on waxy plant substrates, their adhesive pads were contaminated with wax material, however, to different extents depending on

• cases of the plant surfaces covered with wax projections having higher aspect ratios. The data obtained clearly indicated the impact of waxy plant surfaces on the insect ability to subsequently attach to the clean smooth surface. This effect is caused by the contamination of adhesive pads and

Growing up in a rough world: scaling of frictional adhesion and morphology of the Tokay gecko (Gekko gecko)

• Anthony J. Cobos and
• Timothy E. Higham

Beilstein J. Nanotechnol. 2022, 13, 1292–1302, doi:10.3762/bjnano.13.107

• adhesive pads is the contact area between the setae and the surface. With increasingly rough surfaces, the area for contact decreases, leading to decreased adhesive performance. In a modeling framework, the force of adhesion can be related to surface energy of the substrate, the area of the adhering pad

• been found to increase with body size in the southern African gecko Chondrodactylus bibronii [38]. Beyond intraspecific scaling, a recent study found extreme positive allometry in toepad area among animals that have adhesive pads, from mites to geckos [39]. Thus, it is likely that animals of different

Physical constraints lead to parallel evolution of micro- and nanostructures of animal adhesive pads: a review

• Thies H. Büscher and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2021, 12, 725–743, doi:10.3762/bjnano.12.57

• Thies H. Buscher Stanislav N. Gorb Department of Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Am Botanischen Garten 9, 24118 Kiel, Germany 10.3762/bjnano.12.57 Abstract Adhesive pads are functional systems with specific micro- and nanostructures which evolved as

• , hairy systems increase the attachment strength by increasing the hair density and, consequently, increasing the amount of single contacts. This trend, however, differs for multiple reasons among different lineages in which hairy adhesive pads evolved in a convergent manner [250]. The small effective

• attachment pads that differ in the overall morphology rely on similar functional principles. In essence, a high dependency on basic principles leads to a high degree of convergence in animal adhesive pads. Furthermore, the identification of common principles is informative of the most useful solution for

A new bioinspired method for pressure and flow sensing based on the underwater air-retaining surface of the backswimmer Notonecta

• Matthias Mail,
• Adrian Klein,
• Horst Bleckmann,
• Anke Schmitz,
• Torsten Scherer,
• Peter T. Rühr,
• Goran Lovric,
• Robin Fröhlingsdorf,
• Stanislav N. Gorb and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2018, 9, 3039–3047, doi:10.3762/bjnano.9.282

• adhesive pads [6] or the structural colors of Morpho menelaus [7]. Superhydrophobic surfaces are also important in the above context. Several plants and animals, which can maintain stable air layers while submerged (Salvinia effect [8]), have been analyzed. Especially the floating ferns of the genus

Structural and tribometric characterization of biomimetically inspired synthetic "insect adhesives"

• Matthias W. Speidel,
• Malte Kleemeier,
• Andreas Hartwig,
• Klaus Rischka,
• Angelika Ellermann,
• Rolf Daniels and
• Oliver Betz

Beilstein J. Nanotechnol. 2017, 8, 45–63, doi:10.3762/bjnano.8.6

• subsequent tarsal release from the substrate, (3) reducing the loss of tarsal fluid on the substrate, (4) keeping the adhesive compliable for perfect adaption to the surface micro-roughness and (5) protecting of the tarsal adhesive pads from contamination and abrasive damage [15]. In addition, our recently

When the going gets rough – studying the effect of surface roughness on the adhesive abilities of tree frogs

• Niall Crawford,
• Thomas Endlein,
• Jonathan T. Pham,
• Mathis Riehle and
• W. Jon P. Barnes

Beilstein J. Nanotechnol. 2016, 7, 2116–2131, doi:10.3762/bjnano.7.201

• excellent climbing abilities which allow them to efficiently move through their typically arboreal habitat, doing so using specialised adhesive pads found distally on the ventral surface of each toe. The pads stick by means of ‘wet adhesion’, whereby a thin fluid layer is produced by the pad which creates

• [18][19][24]. Comparing performance with other climbing organisms Several previous studies have examined the effect of surface roughness on the climbing capabilities of other adhesive pad bearing organisms. These include animals with hairy rather than smooth adhesive pads, as well as animals which

• possess claws as well as adhesive pads. Additionally, there are studies of plant surfaces that have evolved to be anti-adhesive as far as insects are concerned. The effects of surface roughness on animals with hairy pads (geckos, spiders, insects such as beetles) are reasonably predictable. When the

Surface roughness rather than surface chemistry essentially affects insect adhesion

• Matt W. England,
• Tomoya Sato,
• Makoto Yagihashi,
• Atsushi Hozumi,
• Stanislav N. Gorb and
• Elena V. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1471–1479, doi:10.3762/bjnano.7.139

• to identify the most important parameters influencing insect attachment. Many insects, including beetles, can attach to inverted surfaces using specific hairy adhesive pads, covered with tenent setae, which secrete an adhesive fluid which typically consists of a mixture of alcohols, fatty acids, and

Influence of ambient humidity on the attachment ability of ladybird beetles (Coccinella septempunctata)

• Lars Heepe,
• Jonas O. Wolff and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1322–1329, doi:10.3762/bjnano.7.123

• attachment organ determines its function, but also environmental parameters, such as the surface roughness or/and chemistry of the substrate [1][3][4][5][6][7][8][9]. Also the ambient temperature and humidity may affect the attachment ability of adhesive organs, as it was shown in the dry adhesive pads of

• adhesive pads [6]. Males possess tenent setae with discoidal tips that are assumed to be an adaptation to securely attach to the smooth elytrae of the female during both copulation and mate guarding [6][37]. Two main questions were asked. (1) Does ambient humidity influence the attachment ability of the

• (fluid supplemented) adhesive pad is influenced by ambient humidity. Our results indicate an optimal range of relative humidity with maximal traction forces in ladybird beetles. Similar observations have been made in dry adhesive pads of spiders, using a similar setup and method as in the present study

Functional diversity of resilin in Arthropoda

• Jan Michels,
• Esther Appel and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1241–1259, doi:10.3762/bjnano.7.115

• of hairs (setae) and applied shear force lead to the formation of a maximal real contact area without slippage within the contact [104]. This indicates that material flexibility is very important for the contact formation of adhesive pads. With a minimal normal load, flexible materials can create a

• optimisation that increases the attachment performance of the adhesive pads when they attach to rough surfaces due to an efficient adaptation of the soft and flexible setal tips to the substrate and a simultaneous prevention of setal clusterisation by means of the stiffer setal bases [48]. Since this

• contribute to the adhesion efficiency of adhesive pads in the form of capillary interactions and cleaning effects. With regard to the resilin-dominated setal tips, an additional function is conceivable. As described above, resilin is only soft and flexible when it is hydrated. Accordingly, to keep the

Physical principles of fluid-mediated insect attachment - Shouldn’t insects slip?

• Jan-Henning Dirks

Beilstein J. Nanotechnol. 2014, 5, 1160–1166, doi:10.3762/bjnano.5.127

• Jan-Henning Dirks Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems, Stuttgart, Germany 10.3762/bjnano.5.127 Abstract Insects use either hairy or smooth adhesive pads to safely adhere to various kinds of surfaces. Although the two types of adhesive pads are

• these assumptions are not valid in many cases of insect adhesion. Future tribological models for insect adhesion thus need to incorporate deformable adhesive pads, non-Newtonian properties of the adhesive fluid and/or partially “dry” or solid-like contact between the pad and the substrate. Keywords

• and, in particular, in which it falls short in explaining the forces generated by the adhesive pads of insects. Hairy and smooth adhesive organs of insects One of the most basic biological micro-scale structures for mechanical interlocking to a substrate seems to be a claw. However, the potential use

Insect attachment on crystalline bioinspired wax surfaces formed by alkanes of varying chain lengths

• Elena Gorb,
• Sandro Böhm,
• Nadine Jacky,
• Louis-Philippe Maier,
• Kirstin Dening,
• Sasha Pechook,
• Boaz Pokroy and
• Stanislav Gorb

Beilstein J. Nanotechnol. 2014, 5, 1031–1041, doi:10.3762/bjnano.5.116

• 30 fold, reduction of insect attachment forces on the wax surfaces when compared with the reference glass sample. Attachment of the beetles to the wax substrates probably relied solely on the performance of adhesive pads. We found no influence of the wax coatings on the subsequent attachment ability

• of beetles. The obtained data are explained by the reduction of the real contact between the setal tips of the insect adhesive pads and the wax surfaces due to the micro- and nanoscopic roughness introduced by wax crystals. Experiments with polydimethylsiloxane semi-spheres showed much higher forces

• and microrough substrates, many insects use highly specialised adhesive pads, which may be located on different parts of the leg and are of two different types: smooth and setose (hairy) [2][3]. Due to the material flexibility of smooth pads and fine fibrillar surface microstructures (tenent setae

Fibrillar adhesion with no clusterisation: Functional significance of material gradient along adhesive setae of insects

• Stanislav N. Gorb and
• Alexander E. Filippov

Beilstein J. Nanotechnol. 2014, 5, 837–845, doi:10.3762/bjnano.5.95

• various lineages of arthropods. Keywords: adhesion; attachment; biomechanics; computer modelling; cuticle; locomotion; material; surface; Introduction The contact formation of insect adhesive pads on various substrates depends on the pad ability to adapt to different surface topographies. The quality of

• ]. Due to this reason, the material flexibility is important for contact formation of adhesive pads. Flexible materials may generate large contact area between the pad and substrate at minimal normal load. On the other hand, elongated structures, made of too flexible materials, have low mechanical

• revealed by confocal laser scanning microscopy (CLSM). This gradient is hypothesized to be an evolutionary optimization enhancing adaptation of adhesive pads to rough surfaces, while simultaneously preventing setal clusterisation. Such an optimisation presumably increases the performance of the adhesive

Impact of cell shape in hierarchically structured plant surfaces on the attachment of male Colorado potato beetles (Leptinotarsa decemlineata)

• Bettina Prüm,
• Robin Seidel,
• Holger Florian Bohn and
• Thomas Speck

Beilstein J. Nanotechnol. 2012, 3, 57–64, doi:10.3762/bjnano.3.7

• cuticular folds. For attachment of L. decemlineata, as for many other insects, both adhesive pads and claws are responsible (Figure 3). The hairy adhesive pads of beetles show best attachment on smooth surfaces, or on surfaces with very large diameters of the asperities, as shown in experiments with insects

• films of wax, traction forces were eight times higher than on smooth surfaces showing superimposed microstructuring (relation of i+o to i+wc and i+cf). For surfaces covered with films of wax, we propose that the adhesive pads of L. decemlineata adapt to the surface with a clearly increased contact area

• significant increase in traction forces between convex and papillate epidermal cells was detected. The (macro-) roughness induced by the cell shape should provide sufficient area with smooth surface to establish a close contact between adhesive pads and the substrate [13]. On surfaces showing asperities

The effect of surface anisotropy in the slippery zone of Nepenthes alata pitchers on beetle attachment

• Elena V. Gorb and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2011, 2, 302–310, doi:10.3762/bjnano.2.35

• downward pitcher direction, since, in this direction, they could interlock with overhanging edges of lunate cells. Keywords: adhesive pads; claws; Coccinella septempunctata; insect–plant interactions; traction force; Introduction Pitcher-shaped trapping organs produced at the tips of tendrils are

• , and their effect on insect attachment ability in several Nepenthes species (e.g., [17][18][19][20][21][22][23][24][25][26]). Using different experimental approaches, the authors explained the prevention of insect adhesion via contamination of adhesive pads by wax crystals and/or reduction of the real

• peristome) or downward (towards the pitcher bottom) directions corresponding to the upright or inverted positions of the pitcher. In order to distinguish between the contribution from claw interlocking and from adhesion using tarsal adhesive pads to insect attachment on these surfaces, the performances of