Fact: Snails fed colored paper will poop colored squiggles. Now, silkworms are getting in on the technicolor action: a recent report shows that, after eating mulberry leaves treated with fabric dye, regular larvae will produce cotton-candy-tinted fibers. They're like biological 3D printers for producing colored silk.
The findings, published in the ACS Sustainable Chemistry & Engineering journal, point to an effort to find a more sustainable solution to traditional dyeing methods.
Dissected silkworm glands.
Generally, these require lots and lots of water that, in the end, becomes a chemically contaminated toxic hazard, but applying the pigment before consumption requires way less H2O. Out of seven azo dyes tried, "Direct Acid fast red" gave the most brilliant result—strong enough to give the wiggly little thangs themselves a rosy blush.
It's pretty crazy to think of silkworm farms turned into terrestrial rainbows, with both colored leaves (before) and colored cocoons (after). Perhaps, with enough training, these little living looms can simply weave colored scarves and clothing for you. [Popular Science]