3D printing is the coolest thing since sliced bread, but what should we print with? This could go horribly wrong if we don’t take the opportunity to stop and ask how the rest of nature would do it. Maybe our society friends the paper wasps have an opinion: let’s check in with them in today’s entry of The Biomimicry Manual.
One of my passions is trying to figure out how societies evolve. I’m not talking about the great faceless herds of wildebeest, or swirling, soulless schools of sardine, though I love those too. When I say “societies,” I mean species that group into tightly coordinated bunches, where individuals do different kinds of jobs, together, at the same time. When everyone does their thing in a society, surprising things happen, be it in human cities or underground naked mole rat labyrinths.
Societies aren’t too common among mammals in general though; most are created by insects, but insect societies are a lot like ours. We divide the labor among ourselves, and we will defend our nests alongside family and friends if threatened. Honeybees have hives, ants excavate ant-hills, termites make mounds. But humans make a lot of other stuff too, not just homes. In fact, we can’t stop making stuff, which would be perfectly fine if our medium of choice wasn’t a Pacific-Garbage-Dump’s-worth of petrol plastic. There’s good news, though: I hear we’re on the cusp of a radical manufacturing revolution. Yes, the tantalizing prospect of local, on-demand 3D production, without waste or a distribution footprint dangles before us.
You probably know that a desktop 3D printer is more or less a fancy robotic hot-glue gun. Tiny dots of liquid feedstock squirt through a nozzle, hardening after they leave the printer, and layers of hardened material build on top of one other to make the object. So the first question to ask when we’re trying to decide on a feedstock could be: “How does nature change a liquid into a solid at room temperature?” Humans do it by melting and cooling plastic, and that’s pretty much how 3D printing gets done.
You’ve got your ABS or PLA (and apparently, Weed Wacker line, though this one is the most toxic of all), and neither will break down in a landfill or your backyard compost pile. Even though they are considered “officially safe” for home use (provided you have, you know, a fume hood), heating these materials does produce a nasty chemical ‘scent’ that normal healthy people do not like. Possibly because it gives them headaches and raw skin, and contains large amounts of ultrafine nanoparticles that swim gracefully across their blood-brain barrier. Surely there’s another way. How would the rest of nature do it?
Quite a few creatures make good models for 3D printing, and as usual, most of them are insects. Why is that? Because the little jointy-footed beasts have been around longer than almost everyone else, and they’ve had more time to test out their designs. Basically, they run the FabLab. Silkworms are tried-and-true human collaborators: they make an excellent all-in-one self-replicating freeform printer and biocomputer, programmed by DNA. And of course, their feedstock is impeccable: 100% biodegradable silk, produced on-site, on-demand. Just give them plants to eat. In fact, 6500 Bombinamoryx silkworms “printed” the beautiful Silk Pavilion in the MIT Media Lab lobby.
Caddis flies know their way around the maker space too, in a Kardashian kind of way. Their larvae will assemble protective armor from whatever they find, including Hubert Duprat’s bits of gold, opal, turquoise, rubies, and pearls, gluing it all together with silk. And spiders, of course, are the ultimate 3D print masters, but their technology is hopelessly beyond our pay-grade right now.
Let’s move on to our society friends, who are a little more accessible to human ambitions. My favorite printer in this category is the weaver ant. Crack ant teams grip the edges of leaves with itty bitty bear-trap mandibles (which, by the way, were used by ancient people for sutures). They work together to wrestle the leaf into a tube, and once they get it how they like it, other workers fetch the larvae. Then, using their tender offspring as handheld sewing machines, they stitch the tube into a perfect nest.
Now that’s how child labor is done! But, maybe silk technology is a little too impressive for us. I mean, how do they do that? It comes out as liquid protein and then hardens into silk? It’s biodegradable, renewable, non-toxic, and it’s silk? This one might take a little while to figure out.
But meanwhile, we have the paper wasps. Wasps, completely independent of the Egyptians, invented paper. Waking all alone in Spring, with only the memory of her daughters’ corpses to warm her, the pre-fertilized wasp queen crawls from her winter hidey-hole and begins to scrape bits of wood fiber from fences, logs, and cardboard. She chews the fiber into papier mache, flies to a new nest site, and pastes together a little nest to rear her first workers in. Her daughters take over, mixing their own sticky saliva with recycled cellulose to make a lovely, waterproof nest rivaling the finest Italian endpaper. These delicate cardboard tubes are surprisingly strong, because the wasps instinctively (with their mouthparts) orient all the wood fibers in parallel. They even add ant repellant to the slurry!
Paper seems pretty doable to me, and we have lots of it lying around our recycling bins. So, maybe we can figure out the magic ingredients in wasp spit, grind our old cardboard into paste, and feed it into our printers? This idea pleases me. Maybe I just have too many nanoparticles in my brain, but maybe, it’s so crazy it could work. And if it stops the endless oceanic gyre of discarded Barbie body parts, I think it’s worth a try.
All images via Shutterstock