One of the strongest substances in nature is the stuff of spider webs -- the thread produced can hold more weight than most manufactured materials. Attempts to synthesize the substance have failed, writes PNS commentator Walter Truett Anderson, but a new venture involving gene-splicing shows considerable promise. Anderson, author of "Evolution Isn't What It Used To Be" (W.H. Freeman), is a political scientist who writes widely on technology and global governance.

One of the most amazing substances in nature is the light, flexible, yet incredibly strong material spiders spin out to catch unsuspecting flies and other insects.

Now a Canadian company is on the verge of manufacturing it in quantities, and by a most surprising method -- in the milk of transgenic goats. If the project succeeds -- which seems highly likely -- the product, called "BioSteel" -- may soon be used for a variety of applications, from medical sutures to bulletproof vests to space stations.

The process may also mark a significant step toward the production of other biomaterials -- and the beginnings of a new kind of industrial revolution, based on the use of organic processes instead of minerals. Spiderweb silk has a tensile strength of 300,000 pounds per square inch and is both stronger and lighter than compounds based on steel or petrochemicals. Its impressive properties have been known for a long time, and people have dreamed of being able to produce it for their own uses, perhaps the way the ancient Chinese learned to produce silk from silkworms.

But spiders -- aggressive and territorial -- aren't as easily domesticated as the amiable silkworm. More recently, various biotechnology researchers have tried producing spider silk the way they produce medically useful proteins such as human insulin. This involves inserting the gene for the desired material into bacteria, and then producing larger quantities of it through fermentation. But that produced only a gooey substance with little similarity to the natural product, and no commercial value.

Researchers at Nexia Biotechnologies in Montreal thought there might be a better way -- putting the spider-silk gene into milk animals. From spider to cow or goat may sound like a huge leap, but in a way it was logical, since there are close anatomical similarities between the silk-producing glands of spiders and the milk-producing glands of ruminant animals. When evolution figures out a way to do something, it often does it with different variations in many different species.

The scientists' first efforts in the laboratory involved splicing the spider-silk gene into cells taken from the mammary glands of large animals. The silk genes worked with amazing efficiency in the mammary cells, and Nexia scientists were soon producing high-quality spider silk through cell culture. They then produced a line of transgenic mice to see how it would work in living animals.

That experiment also succeeded. The next step was to get the gene into some full-size milk-producing animals. They selected a type of African goat known for its ability to begin reproducing and lactating at an early age -- as early as three months after birth.

The first transgenic goats will be born this summer. If the goats perform as expected when they mature, Nexia will have the beginnings of a breeding stock, and a working spider-silk dairy early next year. Then the challenge will be to extract the pure silk protein from the milk and spin it into fabric by processes roughly comparable to the way artificial fabrics are manufactured from petrochemical solutions.

Nexia's CEO, Jeffrey Turner, thinks the first uses of BioSteel will be in medicine -- for sutures, possibly for artificial tendons or ligaments. Farther down the line, it might be the stuff of bulletproof vests lighter and stronger than those currently in use, for the coatings of space stations, perhaps even in bridges or other structures.

It is of course a bit early to know where this will lead, but we live in fast-moving times when technological changes often leap ahead of the most optimistic imagination. Clearly it advances a new field of biotechnology -- biomaterials -- which could be not only commercially viable but also have more appeal to environmentalists than some other biotechnology products, since spider silk is both a renewable resource and a biodegradable material.

In some ways this work recalls the dreams of the social philosophers of the early 1900s, who speculated about a shift to "biotechnic" industries in which biological production systems would replace the inorganic machines of the factory and end (or at least reduce) reliance on mineral-based materials.