This artist “fused” spider silk and human skin cells to make a material that can kind of, sort of, deflect a bullet. The statement is (supposed to be) one on transhumanism and technology: if we have the technology to make our skin as strong as a bullet-proof vest, what becomes of safety? What becomes of humanity?
Of course, I’m not much of an artist, but I do know a thing or two about transgenics. I’ll go into what the artist did, practically, and what future technologies she might be basing her art on. What would it mean to be human in an age where ‘human’ can mean practically anything?
The Lure of a Bullet-Proof Human
Jalila Essaidi was inspired by, and is riffing on, stories and myths of invulnerability. Genghis Khan and his silk-woven arrow proof vests. Achilles. “Will we in the near future due to biotechnology no longer need to descend from a godly bloodline in order to have traits like invulnerability?” she asks.
The idea of a doctor that could give your child super-human capacity brings up a host of sociological issues. And I think it is these that the artist really wants to provoke thought and discussion about: “By implementing this bulletproof matrix of spider silk produced by transgenic goats in human skin Essaïdi wants to explore the social, political, ethical and cultural issues surrounding safety in a world with access to new biotechnologies. Issues which arise on the basis of ancient human desire for invulnerability…. With this work Jalila Essaïdi wants to show that safety in its broadest sense is a relative concept, and hence the term bulletproof.”
What does all of that mean? Well, as best as I can interpret, the point is this: invulnerability is tempting. We’d love to be able to walk through a dangerous area without fear for our physical safety. We’d love to be bullet-proof. But just like in the myths, in real life, there is no such thing as bullet-proof. There will always be a better weapon; there will always be danger. Achilles was killed, after all.
What She Did
So how does one, with current technology, make a piece of skin that can withstand a bullet?
Essaidi started with spider silk. In particular, she started with spider-silk proteins made by transgenically modified goats and silkworms. These were spun and woven into a matrix comprised mostly of spider-silk proteins. This matrix was then used as a surface upon which to grow human skin cells. Thus: spider-silk-strengthened human skin.
After about five weeks, the skin cells had formed a fairly complete layer (and were about ready to die); the artist tested whether or not the membrane could withstand a bullet.
And, sometimes, with weakened bullets, it could. Other times, it couldn’t. In short, it didn’t live up to the ratings required for bullet-proof vests, but it was probably better than a normal piece of human skin.
As a symbol, a piece of “human skin” withstanding one bullet only to be pierced by the next one is fairly powerful. As a statement on the escalation of weaponry and the ephemeral nature of safety, I think it survives. But is this transhuman future — where everyone is bullet proof — likely, or even possible?
The Science of the Spider Goat
Let’s start with the good news: spider silk really, truly, is incredibly strong. Stronger-by-weight than kevlar, or steel. And the proteins that it is comprised of can be made by organisms that are not spiders: as I mentioned earlier, goats and silk worms producing spider silk proteins have already been created. And this is fantastic news for people who want to make stronger fibers: these proteins combined with new techniques to spin them could create new bullet-proof vests, and that would be fantastic.
But notice how I said spinning techniques? The strength of a fiber does not just come down to the proteins that it is made of. It’s a matter of getting molecules to line up in an orderly fashion: the better the alignment, and the longer the molecules, the stronger the fiber. The parameters for every fiber are slightly different: sometimes what works for one kind of molecule will make another get caught and snarled on itself. So, pretty clearly, just because you have spider silk proteins doesn’t mean that (a) they’re forming the proper quaternary structures — chains of interlocked proteins held together by chemical forces, or (b) they’re packed into a fiber in a tight and orderly fashion. (Side note: that’s why we’re using silk worms instead of goats: silk worms spin the silk into fibers for their cocoons. BUT it’s also a hiccup because our current method for turning the cocoon into something we can spin into rope-like threads — boiling — destroys the spider-silk protein. Oops.)
Note that it’s entirely plausible to me that Essaidi chose a method of spinning her spider silk that actually gave her a very strong fiber. That’s not where I’m going with this argument. Where I’m going with that is that the keratin matrix that underlies human skin is potentially not analogous to any method that will give a very strong fiber.
As I understand it (at this understanding is fairly limited), to get a strong fiber you want several steps: first, extrusion, which makes long chains of molecules (polymers). Usually, that’s followed by drawing, which compresses those chains together and stretches them out into an even more orderly arrangement. And finally, some form of rope-making or twisting, to combine fibers into a strong rope. (Even a thread is a rope of many fibers, on the molecular scale.) Keratinocytes, the cells which produce the matrix underlying human skin, do exactly zero of these things. Keratin forms into fibers, yes, but those fibers aren’t generally even the length of a cell. They’re arranged in a meshwork instead of an orderly weave. In short, the difference between a piece of silk and a keratin-like mesh of silk proteins is approximately the difference between a piece of wool suiting and a thin layer of unspun wool.
So will advances in transgenics allow for better materials for bullet-proof vests? Absolutely. Will they result in bullet-proof skin? Unlikely, or if so, perhaps only for androids.
Society, Art, and Transhumanism
Let’s broaden this discussion a bit. So what if we can’t use spider silk to make our skin repel bullets — there are plenty of other ways in which our technologies are advancing at such a pace that the “human” of tomorrow may well be unrecognizable to the “human” of today.
You can see it without even going into transgenics. Psychopharmacology has plenty of examples of drugs that — potentially — make us stronger, smarter, more alert, more creative, more whatever. From contact lenses to cochlear implants to advances in prostheses, the ability of technology to mimic or surpass the natural capacity of human organs is already incredible. It is only going to become more impressive in coming years. What does that say about the human condition? What does it mean, when our machines become greater than us? What does it mean when we become our machines?
I’d like to answer this question by going into a little bit of anthropology. Infant chimps are born with the ability to hold onto their mothers. Infant humans are born with the reflex to hold on to their mothers (if you put your finger on their palm, they will grab it) but not the strength or capacity to do so. This has an evolutionary teleological explanation: in humans, brain development is put at a premium as compared to strength of limbs, resulting in babies with bigger heads and weaker arms. It also has an evolutionary effect: a human mother who could not carry her baby with her at all times would likely lose that baby.
But a human mother who couldn’t use her arms until her child was old enough to walk would also be at a disadvantage.
Hence, the sling. You can carry your baby with you, and still have use of both your arms. We are, in a way, cyborg marsupials, and we always have been.
So just like I see little practical difference between using recombinant DNA technologies to generate better crops and selecting for similar traits, I don’t necessarily think that new technologies, which allow us to be stronger and faster and more-whatever, will fundamentally change what it means to be human. We have always relied upon technology.
I suppose the difference now is that we imagine we see a line.