A team of scientists has recently uncovered new evidence of how geckos can deftly scuttle around vertical surfaces without falling off. The animals studied to reveal this ‘new trick to their stick’ were tokay geckos (Gekko gecko).

The research article states that gecko feet, “possess the most hierarchically integrated natural structures that span seven orders of magnitude in size…” The images opposite demonstrate what that means. The ‘hierarchical’ structure of a gecko’s foot (fig. 2) is shown photographed by an electron microscope (fig. 3). Many rows of extremely fine hairs (setae) can be seen, about 1/10 of a millimetre long and densely packed, with 5,000 per square mm (three million per square inch). The end of each seta has up to 1,000 branches, ending in spoonlike structures (spatulae), approximately 0.2–0.5 μm (micrometres—less than 1/50,000 inch) long. All of this is constructed at the molecular level from proteins by molecular machinery, encoded on the DNA—an astounding biological fact!

When these microscopic structures come into contact with a surface, van der Waals (vdW) forces come into play. These are weak electrostatic forces that operate at very small distances. vdW forces are very short-range, decreasing with the sixth power of distance. This is why gecko feet, and gecko-inspired biomimetic sticky tape, need extremely fine hairs so the surfaces can be close enough for vdW forces to operate.

The fact that geckos’ spatulae are so numerous means that a huge surface area is available, producing an overall large attracting force. Tokays demonstrate this in that their entire weight can be suspended from a single, upwardly pointing toe, in contact with a smooth, vertical surface.

Terrific tokay technology

Previously, it was discovered that tokay feet and skin have superhero-like abilities to repel liquids, leading to new gecko-inspired materials. Gecko toe structures have inspired new materials (‘nano-tape’) that take advantage of vdW forces. Under normal conditions, the tape is completely non-sticky, but under shear force, the material’s engineered coating induces vdW forces, enabling the tape to stick strongly to any surface. This allows objects to be lifted or pulled, or surfaces to be climbed by robots (or people) using the tape. As soon as the shear force is reduced, the tape simply falls away from the surface in a similar fashion to how geckos ‘unstick’ their feet. 

More evidence for intelligent design. How could this evolve by random chance. It is ludicrous to think that our schools and universities are teaching evolution as the means by which our complex information-based universe with such diverse living creatures came into being without having any possible plausible mechanism and explanation for how it could have happened.