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

• ). In general, the hairy adhesive pads on the feet of flies, beetles and spiders are densely covered with dense arrays of flexible setae (see Figure 1A) [16][17][18][19][20][21][22]. Although the setae of some beetles branch towards the tip, they only end in a single terminal element in most insects

• . These terminal elements can vary in shape and size, even within one tarsus or between the sexes of one species [23]. Recently it has been shown that in beetles the setae show a decreasing stiffness of the cuticle towards the tip of the setae [24]. Similar “hairy” structures can be found in many other

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

• on wax samples when compared to insect attachment forces measured on these surfaces. We explain these results by the differences in material properties between polydimethylsiloxane probes and tenent setae of C. septempunctata beetles. Among wax surfaces, force experiments showed stronger insect

• 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

• ventrally curved claws with a claw tip diameter of about 4 μm [42] and hairy adhesive pads situated on the ventral side of the two first proximal tarsomeres (Figure 5a). Pads are covered with numerous tiny setae having various tip shapes, from sharp-pointed to spatula-like, ranging in width from ca. 1.8 to

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

• /bjnano.5.95 Abstract It has been recently demonstrated that adhesive tarsal setae of beetles possess material gradients along their length. These gradients presumably represent an evolutionary optimization enhancing the adaptation to rough surfaces while simultaneously preventing clusterisation of the

• setae by lateral collapse. The numerical experiment of the present study has clearly demonstrated that gradient-bearing fibers with short soft tips and stiff bases have greater advantage in maximizing adhesion and minimizing clusterisation in multiple attachment–detachment cycles, if compared to the

• fibers with longer soft tips on the stiff bases and fibers with stiff tips on the soft bases. This study not only manifests the crucial role of gradients in material properties along the setae in beetle fibrillar adhesive system, but predicts that similar gradients must have been convergently evolved in

Functionalization of vertically aligned carbon nanotubes

• Eloise Van Hooijdonk,
• Carla Bittencourt,
• Rony Snyders and
• Jean-François Colomer

Beilstein J. Nanotechnol. 2013, 4, 129–152, doi:10.3762/bjnano.4.14

• demonstration of writing, using patterned aligned nanotubes (Figure 4) [63]. An interesting example of patterned aligned carbon nanotubes is the engineering of gecko-foot-mimetic dry adhesives. Patterning is employed to effectively reproduce the setae of gecko composed of many lobes, aimed at obtaining the

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

• forces are due to an improved grip of the beetles’ claws caused by the elevated cell shape. Furthermore, friction might be increased with the setae possibly getting caught behind the elevated epidermal cells. In plant surfaces possessing epicuticular wax crystals or cuticular folds the influence of cell

• used as a model insect species. This leaf beetle has frequently been used as model insect species for traction experiments and its attachment devices have been well analysed [8][13][29][30]. The tarsus (Figure 3) consists of five tarsomeres, with tarsomeres 1–3 being covered with setae of four

• .: Vitis vinifera, Rosa: Rosa hybrid Floribunda cv. “Sarabande”. SEM micrographs of the attachment devices in a male Leptinotarsa decemlineata. (a) Ventral view of a hind leg; (b) claw tip; (c–f): Tarsal adhesive setae: (c) filamentous, (d) lanceolate, (e) spatula-shaped and (f) discoidal setae

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

• epidermal cells due to the drying process. The tarsus of the C. septempunctata beetle ends distally with two ventrally curved claws having tip diameters of 3.7 ± 0.64 μm (N = 10, Figure 3). Attachment pads belong to the hairy type of locomotory organs in insects. Pads and types of adhesive setae in this

Superhydrophobic surfaces of the water bug Notonecta glauca: a model for friction reduction and air retention

• Petra Ditsche-Kuru,
• Erik S. Schneider,
• Jan-Erik Melskotte,
• Martin Brede,
• Alfred Leder and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2011, 2, 137–144, doi:10.3762/bjnano.2.17

• gaps (underside of elytra) or even vanished completely after a few days (sternites). Moreover, the upper side of the elytra was able to keep an air film up to flow velocities of 5 m/s. Obviously the complex surface structure with tiny dense microtrichia and two types of larger specially shaped setae is

• through water, but most of the time it supports itself from underneath against the water surface with both pairs of fore legs and the tip of the abdomen [26]. The surface of the elytra is covered by a hierarchical structure of larger setae and very small microtrichia. Balmert et al. hypothesized that the

• covered with hairy structures over almost all its body with exception of head, pronotum and legs. The body parts show a large variety of surface structures, but in general two types of surface protuberances occur: Large and sparse setae as well as small and dense microtrichia. Setae have a socket