Dear Dr. Universe: Can you grow stuff like thread, cloth, silk, and most importantly, clothing? – Jay, Colorado
We can use all kinds of animal, bug, and plant materials to make cloth. Even some of the tiniest living things on the planet can make cloth, too.
I heard about this from my friend Hang Liu, a Washington State University professor who studies the science of materials we use and wear every day. These tiny organisms, microbes, do lots of jobs in the world. They’re at work in soil, some help bread rise, and others can sometimes make us sick. Chances are your clothes didn’t come from microbes, though. It’s likely your T-shirt started as a seed.
Plants make something called cellulose. It keeps their cell walls strong. When farmers plant cotton in their fields, the soft cellulose fibers from the plant can be processed into thread and fabrics.
Some microbes can actually spin cellulose into cloth. The recipe for microbe cloth calls for a few ingredients. The main one is kombucha, a sweet tea full of bacteria and yeast. Some people drink it to help with digestion. When sugar, yeast, and more microbes are added to the tea, a thick, gooey layer starts to grow.
After the layer dries out, a very thin, leathery material is leftover. This material can fuse to itself as it dries. It doesn’t have to be sewn together with thread. Designers can shape it into pieces of clothing including shoes and jackets– or even hats with ears, for cats like me.
As Liu told me more about fibers, she pulled a silkworm cocoon out of her office drawer. Silkworms live in mulberry trees, the closest thing to trees that can grow fabric. Mulberry trees can grow their own kind of spongy bark cloth right inside their trunks. The silkworms also help make fabric.
Up in the mulberry branches, they munch on leaves and berries, getting ready to make their cocoons, small waystations they use to get ready for the next stage of their lives. They spin their cocoons with silk that comes right out of their mouths. People use the soft fibers from cocoons to make silk fabric and thread.
Fabric and thread can also be made from animal hair. Wool from llamas and sheep, for example, can also be spun into one of my most favorite things, yarn.
One big part of Liu’s research is figuring out the best way to recycle cloth using her knowledge of these natural materials and fibers. She’s looking for the best ways to make new cotton tee shirts out of old ones. She showed me a spool of recycled cotton fibers she made in her lab. The wispy, white fibers look fragile, but the cotton is very strong.
This kind of sustainable, recycled clothing is good for both the people who wear it and the planet. That’s something that will never go out of style.