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The Namib grass Stipagrostis sabulicola relies, to a large degree, upon fog for its water supply and is able to guide collected water towards the plant base. This directed irrigation of the plant base allows an efficient and rapid uptake of the fog water by the shallow roots. In this contribution, the mechanisms for this directed water flow are analysed. Stipagrostis sabulicola has a highly irregular surface. Advancing contact angle is 988 + 58 and the receding angle is 568 + 98, with a mean of both values of approximately 778. The surface is thus not hydrophobic, shows a substantial contact angle hysteresis and therefore, allows the development of pinned drops of a substantial size. The key factor for the water conduction is the presence of grooves within the leaf surface that run parallel to the long axis of the plant. These grooves provide a guided downslide of drops that have exceeded the maximum size for attachment. It also leads to a minimum of inefficient drop scattering around the plant. The combination of these surface traits together with the tall and upright stature of S. sabulicola contributes to a highly efficient natural fog-collecting system that enables this species to thrive in a hyperarid environment.

In contrast to many arthropods whose locomotion on plant surfaces is impeded by trichomes, the omnivorous mirid bug Dicyphus errans Wolff (Heteroptera, Miridae, Bryocorinae) lives on pubescent plants and preys on a variety of phytophagous arthropods. Morphological (slim body, long slender legs, elongated curved claws) and behavioural (locomotion) adaptations to hairy plant substrates result in higher predation effectiveness and fecundity, as well as a shorter developmental cycle of the bug compared to insects on plants without trichomes. To understand the bug-plant interactions from the biomechanical point of view, the bug's attachment system and the leaf surfaces of various plant species were analysed. Bug attachment ability was estimated in an inversion experiment on the adaxial and abaxial sides of leaves in 40 plant species. Furthermore, bug traction forces on the abaxial leaf side of 14 plant species were measured. Morphometrical variables of trichomes and the adhesive properties of plant surfaces were estimated. The bugs' traction force ranged from 0.07 mN on Brassica oleracea (Brassicaceae) to 1.21 mN on Plectranthus ambiguus (Lamiaceae) and Solanum melongena (Solanaceae). Bugs performed considerably better on hairy surfaces where a significant positive correlation between the force and both the trichome length and diameter was found. The trichome density and aspect ratio did not influence the force. Adhesion properties of plant surfaces covered with trichomes may also significantly impede the traction force. Based on the results obtained, it is concluded that hairy plants provide a more suitable environment for D. errans than either smooth ones or those covered with wax crystals. Hairy plant surfaces are predicted to support stronger attachment and therefore more reliable locomotion of the bug.

Synthetic conductive biopolymers have gained increasing interest in tissue engineering, as they can provide a chemically defined electroconductive and biomimetic microenvironment for cells. In addition to low cytotoxicity and high biocompatibility, injectability and adhesiveness are important for many biomedical applications but have proven to be very challenging. Recent results show that fascinating material properties can be realized with a bioinspired hybrid network, especially through the synergy between irreversible covalent crosslinking and reversible noncovalent self‐assembly. Herein, a polysaccharide‐based conductive hydrogel crosslinked through noncovalent and reversible covalent reactions is reported. The hybrid material exhibits rheological properties associated with dynamic networks such as self‐healing and stress relaxation. Moreover, through fine‐tuning the network dynamics by varying covalent/noncovalent crosslinking content and incorporating electroconductive polymers, the resulting materials exhibit electroconductivity and reliable adhesive strength, at a similar range to that of clinically used fibrin glue. The conductive soft adhesives exhibit high cytocompatibility in 2D/3D cell cultures and can promote myogenic differentiation of myoblast cells. The heparin‐containing electroconductive adhesive shows high biocompatibility in immunocompetent mice, both for topical application and as injectable materials. The materials could have utilities in many biomedical applications, especially in the area of cardiovascular diseases and wound dressing.

Galium aparine is a herbaceous climbing plant that attaches to host plants mainly via its leaves, which are covered by hooked trichomes. Although such hooks are found on both leaf surfaces, the leaves of G. aparine are mainly positioned upon the leaves of supporting plants and rarely beneath. In order to understand the mechanism underlying this observation, we have studied structural and mechanical properties of single leaf hooks, frictional properties of leaf surfaces, turgor pressure in different leaf tissues and bending properties of the leaves in different directions. Abaxial and adaxial leaf hooks differ significantly in orientation, distribution, structure and mechanical properties. In accordance with these differences, friction properties of leaves depend on the direction of the applied force and differ significantly between both leaf surfaces. This results in a ratchet mechanism. Abaxial leaf hooks provide strong attachment upon the leaves of adjacent plants, whereas adaxial hooks cause a gliding-off from the underside of the leaves of host plants. Thus, the leaves of G. aparine can function as attachment organs, and simultaneously orient themselves advantageously for their photosynthetic function. Further adaptations in turgor pressure or concerning an anisotropy of the flexural stiffness of the leaves have not been found.