NASCAR, the NBA, Rubber and the Rainforest

As you watch the NBA playoffs this spring, impress your friends with this fact: the idea for those Nikes worn by LeBron James and Kevin Durant was actually born in the rainforests of the northeast Amazon.

In 1775, French botanist Fusee Aublet observed local Indians there coating their feet with rubber tree sap and holding their feet over the fire, creating the first custom-made athletic shoes.

Obviously, top-of-the-line footwear has more impact on NBA players' health, performance, and longevity than any other part of their uniforms. But here's the catch: only natural rubber has the elasticity and durability required to meet the NBA's exacting standards. Synthetic rubber simply cannot do the job. With 360 to 450 players in each season, the NBA literally runs on rubber.

The case is similar for NASCAR. The races, which boast 75 million fans worldwide and generate $3 billion a year in spinoff products, depend largely on natural rubber. Even today, when almost any natural compounds can be mimicked synthetically, natural rubber offers a toughness that cannot be beat. With NASCAR speeds exceeding 200 mph, precision starting, stopping, and turning can literally mean the difference between life and death. A race tire can be up to 65 percent synthetic, but requires at least 35 percent natural rubber.

Few realize that the origin of this unique compound lies in the South American rainforest. In the 1800's, British explorer Henry Wickham took seeds from the Brazilian Amazon and had colleagues plant them in tropical Africa and Asia. With no natural pests, the plantations in Asia were a spectacular success, and most natural rubber today is grown in plantations across Southeast Asia.

The first scientific interest in rubber was the direct result of French explorer, mathematician, and geographer Charles Marie de La Condamine's expedition in the 1730s. While in lowland South America, La Condamine made detailed observations on rubber trees, and when he returned to Paris his notes and specimens introduced rubber to Europe's scientific community.

From there, a series of discoveries led to rubber's increasing popularity and utility. In 1770, Joseph Priestley, an English clergyman and chemist who helped identify oxygen, observed that a piece of Amazonian latex was effective in rubbing out pencil marks on paper. The realization led Priestley to name the compound "rubber."

Five years later, when Aublet observed Indians in French Guiana applying rubber to their feet, he never could have guessed the critical role the substance would play in the Western world, where it has repeatedly influenced the course of history.

In World War II, access to rubber was imperative. The day after the attack on Pearl Harbor, the Japanese invaded Malaya and the Dutch East Indies, giving the Axis control of about 90 percent of global rubber supplies and restricting other western nations' access to this strategic material material. The diminished access to rubber created a serious bottleneck in Allied weapon production. Each Sherman tank required a half a ton of rubber, and some warships contained 20,000 rubber parts. Rubber was used to coat most of the wires used in every factory, home, office, and military facility throughout the U.S. and overseas. Having access to sufficient quantities of natural rubber was considered vital to the war effort by both the Allies and the Axis.

I detailed the paramount value of rubber for 20th century warfare in my book Medicine Quest (2000):

"In mid-1944, the giant Japanese submarine I-52 departed from its homeport and headed for a secret Atlantic rendezvous with a German U-boat. The assignment: trade Japan's most valuable raw materials for German weapons technology. On the night of June 23, 1944, I-52 met up with German U-530. Allied cryptographers had cracked the Axis codes, however, and an Allied bomber sank the Japanese sub, killing everyone on board. Fifty years, later, using sonar technologies developed in the search for the Titanic, explorer Paul Tidwell found the sub in 17,000 feet of water. What had the sub been carrying when she was spotted and sunk? Gold, rubber and three tons of quinine."

The region's most famous expeditions in search of wild Amazonian rubber during this time were led by the late Harvard ethnobotanist Richard Schultes, who spent 14 years charting rivers that few outsiders had ever seen while collecting hundreds of plants new to science. The rubber plants he carefully collected during these treks were planted in a botanical garden in Costa Rica where they could be both safeguarded and studied and serve as the source of new high-yielding and disease resistant strains. After a change in directorship at the botanical garden, the rubber program was terminated and nearly all of the trees that Schultes had suffered to bring back were felled and replaced with sugarcane and manioc. Many of those rare varieties of rubber have not been seen or recollected since.

As Wade Davis (Schultes' biographer and a fellow ethnobotanist) asserts in his book One River, had the rubber program continued, "... one can be almost certain that today there would be healthy, blight-resistant plantations growing close to home in the Americas." As a result of this highly improvident decision in Costa Rica, the world's supply of natural rubber is not protected by disease-resistant varieties that Schultes and his colleagues struggled so hard to locate and bring back. Should a bacteria or virus attack monoculture plantations of rubber trees in Asia, we will need wild relatives of these trees to increase resistance to pests and diseases.

Even in our hyper-technical age, we cannot manufacture a synthetic rubber with all the qualities of the natural product including its resilience and tensile strength, resistance to abrasion, water resistance, and ability to absorb impact without generating heat. In consequence, a range of flexible products that demand a high-performing base compound--such as surgical gloves, condoms, and even rubber bands and erasers--tend to use natural rubber.

In 1839, Charles Goodyear invented the process of vulcanization in Springfield, Massachusetts by adding sulfur to natural rubber, making the substance more durable and stable and thereby enormously expanding its utility. Goodyear, though, is less well known for patenting the first rubber condom just five years later. Prior to this, condoms had been made of oiled silk paper, leather, lamb intestines, and even tortoise shell. Perhaps his efforts in this regard are deserving of more than a sidebar in the history texts!

As a result of narrow genetic diversity, botanists know and worry that the rubber trees grown in monoculture plantations in the Asian tropics are susceptible to pests and diseases. In order to prevent this, we must make certain we have access to disease-resistant rubber to crossbreed with domesticated varieties. In this way, we can increase yields and resistance to blights. The recent expansion of Colombia's Chiribiquete National Park--which harbors several distinct varieties of rubber trees--is an important step in protecting wild varieties, but more must be done.
Rubber represents a commodity that will remain essential for the foreseeable future. Therefore, protection of the rainforest and, indeed, all species everywhere is in our own self-interest.