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Lac
The insect Laccifer lacca - or just plain "lac" - lives on trees in India and Southeast Asia. It secretes a resin, also called lac, a polymer from which people make lacquer and shellac. They use these varnishes to coat ships, houses, furniture, fruit, pills, and candy. So you'll never lack lacquer if you've got enough lacs. Ack!
Rosin
Dead wood and pulp from pine trees contain a polymer called rosin, which is used to make varnish and soap. Violinists rub rosin on the horsehairs in their bows to make them slide smoothly across the strings. Gymnasts and baseball players use rosin to improve their grips.
Silkworm
Silkworms, which are actually caterpillars, are raised on silk farms and fed mulberry leaves. People in China discovered more than 4,500 years ago that they could unravel silk, a polymer, from the worms' cocoons and weave it into soft fabrics.Incredibly, a single cocoon yields 330 to 980 yards (300 to 900 meters) of silk. For centuries, silk was so prized that exporting mulberry seeds or silkworm eggs from China was punished by death.
Turtle Shells
Turtles and tortoises, their land-dwelling cousins, never stray far from home since they carry it around on their backs. That's no small task for the largest, which reach 8 feet (2.4 meters) in length and weigh nearly 2,000 pounds (900 kilograms). Plates made of bone and encased in hornÑboth constructed of polymers-form the turtle's tough shell. People once used the hawksbill turtle's shell to make hair combs and eyeglass frames. Now that these turtles are endangered, most "tortoise shell" is made from a plastic substitute.
Animal Horns
Antelope, buffalo, sheep, cattle, and rhinoceroses all have horns. Unlike a deer's antlers, made of bone, horns are made of the polymer keratin. Parts of you are made of keratin too: It's the primary ingredient in our hair and fingernails. Keratin in the outermost layer of your skin makes you waterproof like other mammals, so you don't get waterlogged the moment you dive in the pool.
Amber
Fossilized tree sap made of resin polymers can become yellow, orange, or brown amber. Ancient Greeks called amber "elektron," and its ability to give a static electrical shock gave electrons and electricity their names. Scientists have retrieved intact genetic polymers, DNA, from ancient insects trapped in amber. Some even think the tiny bubbles in amber might hold the last remaining samples of air breathed by dinosaurs more than 60 million years ago.
Milk
Drink up! Cow's milk is loaded with the polymer casein, a protein. Without this polymer, cheese would come unglued. Glue would come unglued too, since casein from milk provides its sticking power. Casein also winds up in buttons, as well as rhinestones and other artificial gemstones.
Latex
South American Indians slash the bark of trees in the rain forest to obtain a milky white fluid called latex. They discovered that it could form a solid that was elastic; you could stretch it and it would snap back to its original shape. If you rubbed it on penciled words, the writing would disappear, so Europeans called it rubber. They pressed it between layers of fabric to produce a rain slicker called a mackintosh; they also molded it into tires for carriages and automobiles. The British smuggled rubber tree seeds from Brazil to England, where they produced seedlings for export to colonies in Ceylon, Malaysia, and Singapore. Descendants of those seeds now produce 90 percent of the world's natural rubber.
