In the last several years, we've learned just how much deforestation and climate change have affected wild animals and led to many species becoming extinct or endangered. Now, we can add wild coffee to that growing list.

Scientists from the Royal Botanic Garden, Kew in London evaluated more than 20 years of research on 124 wild coffee species and discovered that more than half are under threat of extinction.

"Among the coffee species threatened with extinction are those that have potential to be used to breed and develop the coffees of the future, including those resistant to disease and capable of withstanding worsening climatic conditions," wrote Aaron Davis, head of coffee research at Kew. "The use and development of wild coffee resources could be key to the long-term sustainability of the coffee sector. Targeted action is urgently required in specific tropical countries, particularly in Africa, to protect the future of coffee."

Currently, the coffee industry primarily relies on two types: Arabica and Robusta. Arabica is now classified as an endangered species on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Therefore, it's vital that measures be taken to protect the wild coffee species because they could be used in future plant crop development if the Arabica plant becomes extinct.

"This is the first time an IUCN Red List assessment has been carried out to find the extinction risk of the world’s coffee, and the results are worrying," wrote Eimear Nic Lughadha, senior research leader in Kew’s conservation department and lead scientist for Kew’s plant assessment unit. "A figure of 60 percent of all coffee species threatened with extinction is extremely high, especially when you compare this to a global estimate of 22 percent for plants. Some of the coffee species assessed have not been seen in the wild for more than 100 years, and it is possible that some may already be extinct."

Why Arabica coffee could be gone in our lifetime

Coffee cup and coffee beans on table Arabica is the most widely-traded coffee in the world. (Photo: portumen/Shutterstock)

Arabica coffee is widely used in commercial coffee farming and is also disease-resistant, which is why it the world's most popular coffee. But it could be extinct in the next 50 years.

Arabica coffee is grown all over the world, but it originated in the highlands of southern Ethiopia, where the wild plants have always had a restricted range. Back in 2012, scientists from Ethiopia and Kew Gardens in the United Kingdom took a look at those ranges under various climate change models to see how the coffee would be impacted. They found that in even the best-case scenarios, wild Arabica would lose 65 percent of its suitable habitat before the end of the century. In other models, that number rose to 99.7 percent.

The scientists warn that these predications are on the conservative side, since climate change models do not factor in deforestation — Ethiopia's human population has nearly doubled in the past 40 years — or changes in wildlife distribution, such as the presence of migrating birds that help distribute the coffee plants' seeds.

The effect, according to the researchers, will not be limited to wild Arabica plants. Arabica is the only coffee cultivated in Ethiopia, where it plays an important role in the country's economy. Coffee there is harvested from plantations, semi-domesticated forest sites and the wild. All of those sources could be affected.

Meanwhile, climate change will also pose a threat to Arabica production around the world. The scientists found that the Arabica grown on plantations worldwide has a limited genetic diversity, making it more susceptible to the direct effects of climate change or to pests and diseases, which could also accompany global warming. This makes the wild plants in Ethiopia even more important as a source of broader genetic material for cultivated coffee, as they contain an estimated 95 to 99 percent of the species' total genetic diversity.

Overall, there is one key takeaway from the Key studies conducted over the years. "We hope our findings will be used to influence the work of scientists, policy makers and coffee sector stakeholders to secure the future of coffee production — not only for coffee lovers around the world, but also as a source of income for farming communities in some of the most impoverished places in the world," wrote Davis.

Editor's note: This article has been updated since it was originally published in November 2012.

Scientists discover 60% wild coffee species are under threat of extinction
The world's most popular type, Arabica, is now listed as endangered.