Copying Spider Silk
Posted: November 1, 2019
Cheryl Hayashi has some strange tools for a librarian. She uses fine-tipped tweezers and a powerful microscope. They allow her to dissectthe body of a silver garden spider. She is looking for its hundreds of silk glands.
Dr. Hayashi’s lab is at the American Museum of Natural History in New York City. She is looking for all types of spider silk. It’s a big job. There are at least 48,000 kinds of spiders around the world.
“They make so many kinds of silk,” says Dr. Hayashi. She has collected glands from about 50 kinds of spiders. It has taken her 20 years!
The library could be filled with all of Dr. Hayashi’s specimens and more. Scientists are always looking for stronger and lighter materials. Bulletproof vests, space gear, and even clothing could be made from spider silk one day.
All spider silks start out like thick honey. Spiders make it and stash it in a gland until they want to use it. Then a narrow nozzle called a “spigot” opens. The goo flows out. It is woven together with other strands coming from other spigots.
Nobody knows how many kinds of spider silks there are. Orb-weaving spiders make seven! Some silks are sticky to catch prey. Some are stretchy to hold wiggly insects. Others are tough as steel to support the dangling spider.
Researcher Sarah Stellwagen works at the University of Maryland. Her job is to learn why the silks do what they do. She examines spiders’ genes. Finding the genes has not been easy because spider gland genes were chopped up in early research. Scientists need to recover a full gene to imitate natural silk correctly, or “it’s not as good as what a spider makes,” Ms. Stellwagen says. New technology is helping them do that.
A group of scientists made a small amount of silk last year. They used bacteria. It matched an orb-weaving spider’s dragline silk.
But that was only one type of silk from one species. Dr. Hayashi asks, “What about the other [47,999]?”
[God] does great things beyond searching out, and marvelous things beyond number. — Job 9:10