Humans cannot intrinsically be ‘spidermen’ because of their size, explain scientists of a new study. However, they also provide insight into how we might become ‘spidermen’. The findings are published in PNAS.
What makes one creature able to walk on vertical walls when another cannot? The new research conducted by a team from the Department of Zoology of the University of Cambridge argues it is all about size after studying animals of varying body surface areas (from the very small as mites to the extremely big like whales) in terms of their adherence ability to vertical surfaces.
The findings show that geckos are the largest animals endowed with the ability to scale vertical surfaces. The bigger you get, the more do you need sticking power to stay glued to vertical surfaces. Eventually, size becomes a limiting factor, and creatures larger than the geckos do not have the ability. Humans, therefore, lag behind by a long shot. Safe to say that Ant-man is more realistic than Spiderman, then?!
Were humans to scale vertical walls as Spiderman does, they would need exceedingly large sticky footpads. The rule, as pointed out by the team led by Dr David Labonte, dictates that the larger the organism, the greater pads they would require. They came to this conclusion after they discovered that geckos use around 200 times more of their total body area for adhesive pads than tiny mites. Comparatively, a human would need adhesive pads over 40% of his body surface, or 80 % of his front, to achieve Spiderman’s feats; to put it another way, we would need impossibly large feet. If humans were to be gecko-men, their shoe would have to be of size 145 (European standards) or 114 (US standards), according to senior author Walter Federle.
Labonte explains that the requirement of such morphological changes to provide a greater coverage for adherence would make the evolution of this characteristic to be impractical. But, worry not. There is a solution for this, as is obvious in nature: larger animals have been gifted with other features to climb like claws and toes. On the other hand, small animals have displayed another possibility: having stickier pads, as is the case with some frogs.
As for humans, we are known to push our limits through our intelligence. The knowledge of why humans cannot do Spiderman activities can actually be used to fuel the development of bio-inspired adhesives on a large-scale.
Labonte adds that more work has to be done to investigate the vertical-wall-scaling strategies conferred on animals. He believes further studies in this domain will lead to the development of “powerful and controllable adhesives”. Who knows, this might even pave the way to us becoming Spiderman some day.