1. Introduction. For attachment and propulsion generation during locomotion, different surface adaptations have been evolved in the course of animal evolution. Some of these structures have been well structurally studied, but their functional mechanisms, based on the interplay between the ultrastructure, material properties and physical interactions remained unresolved until recently. The reason for this is that such research requires approaches of several disciplines: zoology, structural biology, biomechanics, physics, and surface science. In addition to the use of a wide variety of microscopy techniques, we established a set of experimental designs that allows obtaining information about adhesive and frictional properties, as well as local and global mechanical properties of materials of animal attachment devices (part 1) and belly surface of the snake skin (part 2), in order to understand tribological mechanisms behind these biological surfaces.

2. Attachment: flies, spiders, geckos on the ceiling. In order to show different functional principles, we experimentally tested about 600 different locomotory attachment devices on legs of insects (Figure 1), spiders and geckos and tried to outline general rules of the interrelationship between their structure and function. Since these broad comparative studies include a wide variety of organisms, some questions about the evolution of these systems could be resolved.

3. Snake skin tribology. Owing to the lack of extremities, the ventral body side of snakes is in almost continuous contact with the substrate. In spite of this, snakes are one of the most successful animal groups in occupying various ecological niches. From a tribology point of view, their ventral skin surface has to fulfill two opposite functions: (1) to support body propulsion during locomotion by generating high friction in contact with the substrate and (2) to reduce skin material abrasion by generating low friction in forward sliding along the substrate.