Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg. (Euphorbiaceae)



Coloured illustration of Hevea brasiliensis from Koehler's 'Medizinal Pflanzen' (1890; vol. 3, t.8). Stem of young Hevea brasiliensis tree growing in Oxford Botanic Garden.

When Europeans discovered sixteenth-century Mesoamerican cultures, they also discovered rubber, a novel elastic, waterproof material. Mesoamericans had been using rubber for at least 2,500 years to make the balls for their ritual and sport, the ballgame ulama. The discovery rubber could be moulded by dissolving it in organic solvents and its elastic properties altered by vulcanisation transformed it from a botanical curiosity to a vital industrial raw material. By the early twentieth century, the rubber age was underway but at the cost of millions of lives in the killing fields of Amazonian and Congolian commerce.

Rubber, a polymer of colourless, volatile isoprenes, is seen as latex ('milk') when some plants are damaged. Latexes, found in special vessels in the bark, are part of the plant's defence system against herbivores or disease attack. By carefully cutting the bark, vessels are broken and the latex repeatedly tapped without killing the plant.

In 1869, Pará rubber, extracted from a tree native to the Brazilian Amazon, was identified as an ideal rubber because of its chemical properties and the prospect that the British could control supply by growing it in southeast Asia. However, the British establishment did not understand Pará rubber biology and had no seed or knowledge of rubber extraction.

The British adventurer and aspiring plantation owner Henry Wickham filled this gap; he knew the tree in Amazonia. Wickham delivered 70,000 seeds, collected in Brazil, to Joseph Hooker, Director of Kew, in the early hours of the 14th June 1876. These were promptly planted and in August 1876, nearly 2,000 seedlings were sent to Sri Lanka. As the British were establishing Pará rubber plantations across south east Asia, the Amazonian rubber boom gathered pace. However, by 1912, the Amazonian rubber balloon had been punctured; rubber could be extracted more cheaply and efficiently from the British-controlled plantations in southeast Asia. For over a century, the means by which Wickham obtained his seeds has been debated. Wickham's involvement in the rubber story is sometimes considered a tangible example of where the artfulness of biopiracy leads.

Today, tens of millions of tonnes of rubber are produced annually from plantations in south east Asia. The single most important use of natural rubber is in the manufacture of tyres, seals and tubes. Through it use as the raw material for condoms, Pará rubber also has positive social effects on family planning and the control of sexually transmitted diseases.

Further reading

Dean W 1987. Brazil and the struggle for rubber: a study in environmental history. Cambridge University Press.

Jackson J 2008. The thief at the end of the world. Rubber, power, and the seeds of empire. Duckworth Overlook.

Whittington EM 2001. The sport of life and death: the Mesoamerican ballgame. Thames & Hudson.

Stephen Harris