So we’ve all seen/read/heard of Spider-ManSpider-Man Bio courtesy of Marvel right? Geeky socially inept boy with an affinity for science gets bitten by a radioactive spider and hey presto; he’s suddenly developing all manners of cool powers. He’s got the proportional strength and agility of an arachnid, a spooky sixth sense that warns him of danger and the ability to cling to walls.
Now, this is a series that strongly relies on science as a means for heroes and villains alike gaining their powers, enhancements and weaponry. Meaning that over the course of this blog I will spend a fair bit of time wandering through the world of our friendly neighbourhood Spider-Man; but fear not, I will spread it out so if you’re not a particular fan of Spidey hopefully there’s something more up your alley coming soon.
If we entirely skip past what the realities of exposure to radiation mean for a human being for the moment, because frankly radiation is a popular theme in the comic book world and I intend to touch upon that with a whole range of characters later, I want to start with his famous wall climbing.
I’m sure that at some point in your lives you’ve all been sat in a room in your house, casually minding your own business when suddenly out of the corner of your eye you catch movement on the wall or ceiling. Lo and behold, it’s a spider. Hazarding a guess, I’d say you’re potentially panicking because you hate spiders or maybe you’re more like me and you’ve thought ‘How does it bloody manage that?’ The very simple answer is that those beasties are hairy.A more thorough explanation of a spiders sticking abilities Insanely hairy. We’re talking they have hairs on their hairs kind of hairy here. Collectively, these individual hairs are called setae and they generally have over half a million of them all over their body. Setae alone aren’t what give them the ability to climb walls though; so in case any of you have visions of a spider being covered in pickaxe like hairs, gouging tiny footholds in your walls, stahp. Van der Waals forces are at work here; basically it’s similar to them being covered in hundreds of thousands of tiny magnets. Oppositely charged molecules that are microscopically close to each other enjoy a mutual attraction, thus keeping the crawly buggers attached to walls, ceilings, glass and so on and so forth.
To bring that back to Spider-Man, some of you may remember that in the 2002 film there was a scene that showed us a lovely up close and personal image of Parker’s hands. Spider-Man (2002 film) Sam Raimi Those hands had a smattering of short, thorn-like structures protruding from his fingertips.
The assumption from this scene is that these structures act for Parker the same way that setae do for spiders. This would be great; if not for the fact that despite their proportional strength a spider tends to need at least 2 of their 8 legs on a surface to stay on it and that once the size of a spider increases to say oh, tarantula proportions the van der Waals force is no longer capable of holding them up. In fact, larger spiders actually secrete a small amount of silky adhesive from their feetTarantulas silky feet explained resulting in adorable little footprints as they walk over surfaces. Between that and the fact that I’m fairly sure MJ or Gwen would have, at some point, had something to say about those hairy, hairy hands the idea of him being capable of climbing surfaces like a spider starts to become less feasible.
Climbing surfaces like a gecko on the other hand; now that’s something I can get on board with. A gecko uses pretty much the same principle. The difference being however that a gecko is capable of remaining attached to a surface with one toe. Impressive huh? A gecko is so lightweight and has such an extreme number of these tiny hairs that the surface area their feet take up is huge in comparison to their size. In fact if a mature gecko could have all their hairs making contact with a surface at one time, it should, mathematically, be capable of supporting up to about 290lbs (roughly 20 stone).
Unfortunately, when it comes to all that wall climbing fun it would seem that Spider-Man really isn’t entirely spider like about it. Unless of course he does have some sticky excretions going on alongside that hair, but that doesn’t bear thinking about. No, it’s more like a Gecko-Man situation here. Don’t worry Spidey wannabes; scientists have already created materials more effective at creating dry adhesive than our lizard friends.How scientists cracked wall climbing There’s hope for you yet!
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