Spider-Man’s wall-climbing abilities are impossible for humans to replicate, new research from researchers at Cambridge has found.

A study conducted by scientists in Cambridge, Australia and the USA has shown that without “impractically large sticky feet” and 40 per cent of our bodies covered in sticky footpads, humans wouldn’t be able to climb walls as Spider-Man does.

The researchers compared 225 different species, looking at the weight and footpad size of frogs, lizards, spiders and insects in hopes of developing large-scale, bio-inspired adhesives.

Despite looking at many different species, Dr David Labonte from University of Cambridge’s Department of Zoology notes “their sticky feet are remarkably similar”.
He added, “When this happens, it’s a clear sign that it must be a very good solution”.

However, geckos are the largest animals able to scale vertical walls, and as the size of an animal increases, the amount of body surface per volume decreases, meaning the amount of sticky footpads needed to support the animal increases.

Labonte explained that “This poses a problem for larger climbing animals because, when they are bigger and heavier, they need more sticking power, but they have comparatively less body surface available for sticky footpads”.

For a human to achieve the same thing they would need “shoes in European size 145 or US size 114,” says Walter Federie, from the same department. Humans would need 40 per cent of our body to be covered in sticky footpads, or 80 per cent of our front.

However, there is another way some larger animals are able to stick, by having stickier footpads. Christofer Clemente, a co-author from the University of the Sunshine Coast, notes that in some closely related species “pad size was not increasing fast enough to match body size yet these animals could still stick to walls”.

“We found that tree frogs have switched to this second option of making pads stickier rather than bigger. It’s remarkable that we see two different evolutionary solutions to the problem of getting big and sticking to walls”.

Labonte stated that there is still interesting work to be done concerning the strategies animals use to make their footpads stickier. “These would likely have very useful applications in the development of large-scale, powerful yet controllable adhesives”.