Closer to Hermes

Some years ago the exoskeleton was a thing of the future and could even be dismissed as the daydream of those who live in a Robocop world. But now, in April 2015, a walking device is presented and described in Nature, which is indeed a partial exoskeleton. It has been developed at North Carolina State University. Like a boot it envelops the foot up to the calf. The secret of its magic consists of a special spring, which runs outside the lower leg from the ankle to the calf muscle. The metal tension of the spring absorbs the energy of the stretching movement of walking and gives it back to strengthen the next take-off. The whole contraption weighs only 500 g and is expected to be of great help to people with impeded mobility. However, there is no reason why healthy people will not use it as well; it allows them to walk both easier and faster. (See Davide Castelvecchi’s contribution ‘Exoskeleton boots improve on evolution’, 1 April 2015,

Again we are reminded of Freud’s conclusion that man is a Prothesengott. So many of our inventions can be called prostheses because they are artificial extensions of our natural organs, senses and limbs. If this new walking device is not making us more godlike, it at least brings us closer to Hermes, whose winged feet enabled him to be the messenger of the gods.

Hermes exoskeleton walking device


The inventors call this partial exoskeleton an improvement on evolution. Its spring duplicates the function of the Achilles tendon and is supposed to be stronger. However, the secret workings of coincidence have achieved that, in the very same newspaper that announced the glorious arrival of the walking device, I stumbled on no less than three items that demonstrate the power of evolution. First there is ‘Little Foot’ (what’s in a name), the impressive skull and skeleton of an ape-man found in a cave in South-Africa’s Sterkfontein. Its age is calculated at 3.67 million years, so it is older than Lucy. Palaeontologist Ronald Clark, who discovered the first parts of ‘Little Foot’, thinks it represents a new species, and he gave it the beautiful name of Australopithecus prometheus. We may safely assume that this promethean was equipped with fully developed, natural legs, which proves that the Achilles tendon too is at least 3.67 million years old. Imperfection seems to have served us well.

Then there is the gecko. Another newspaper article reports that studying the gecko (Lucasium steindachneri) under an electron microscope has led to the discovery that its skin not just repels water, it literally makes water drops and dew bounce. This subtle process not only keeps the gecko dry, the bouncing drops also keep it unbelievably clean. The secret of this gecko’s own dry-cleaning lies in the hundreds of thousands tiny hairs (invisible to our naked eye) that cover its skin. Here evolution has devised a system that allows a small creature to go from wet grass to dry sand without a drop or grain clinging to its smooth skin. Man’s best fabrics do not equal the gecko’s skin. Nature, given enough time, can build something like an exoskeleton, in this case consisting of a protecting and streamlining ‘cover’ of very small hairs in immense density.

The third example of what the power of evolution can do comes, again, from the same newspaper. A North American songbird, the blackpoll warbler, likes to spend its winters in Colombia and Venezuela. GPS-tracking of these birds has shown that they can fly this distance of 2500 km non-stop. They cover it (in autumn mainly over the ocean, and back in spring mainly over land) in just three days. The nimble warbler, with its white cheeks and black capped head, on average weighs between 12 and 15 g. Any grown-up man can hold it between his thumb and forefinger. In evolution’s champions endurance and vulnerability often go together. This winged little friend is a true messenger of the gods, still closer to Hermes than modern techno-man.