The comic book hero Spiderman spins webs that enable him to swing from tall buildings and entrap bad guys. This idea is not entirely science fiction as scientists have known that weight-for-weight, spider silk is stronger than steel. This strength and toughness is combined with high elasticity that enables the material to be stretched several times its length before rupture. The toughest known spider silk is spun by a species called Darwin’s bark spider, discovered in Madagascar in 2001. This spider’s webs span the width of an entire river and have been tested to have a strength 10 times that of Kevlar, the material used to make bullet proof vests.
For many years, scientists have studied if spider silk could be produced in farms in the manner of silk from silkworms. Silkworms produce enormous quantities of silk but the fiber is fragile. Spiders however produce only small amounts of fiber and cannot be farmed, in part because they eat one another. Enter genetic engineering. A University of Wyoming research team led by Professor Don Jarvis, injected spider genes into silkworms to create a laboratory species that produces silk in large quantity and with much greater strength. This experiment could lead to commercial farming of spider-silkworms that produce a new class of high strength natural fiber.
The immediate application for this material could be in the medical profession for making stronger sutures for muscle and ligament repair and for making medical implants. Spider silk could also make a more comfortable bullet proof vest than Kevlar. Other applications could emerge to substitute plastic fibers made from hydrocarbons.
Genetic modification of natural life forms has always been a controversial topic. Many scientists are rightly concerned that these life forms could escape into nature and mutate and cross breed to create other life forms that could have unintended and largely unknown consequences. For now, the University of Wyoming experiment represents a major scientific advance in exploring the benefits of genetic engineering.