Millions of people around the world enjoy a daily cup of coffee; however, their daily caffeine fix could be under threat because climate change is killing coffee plants, putting farmers' livelihoods at risk.
Inside the vast, steamy greenhouses at the Royal Botanic Gardens at Kew in the leafy suburbs of west London, Aaron Davis leads research into coffee.
The cultivation of Arabica and Robusta coffee beans accounts for millions of livelihoods across Africa, South America and Asia.
According to Davis, Arabica is a cool tropical plant - it doesn't like high temperatures. Robusta is a plant that likes even moist conditions - it likes high rainfall. And under climate change, rainfall patters are being modified, and it's also experiencing problems. In some cases, yields are dramatically reduced because of increased temperatures or reduced rainfall. But in some cases, as seen in Ethiopia, you might get a complete harvest failure and death of the trees.
The solution could be growing deep in the forests of West Africa. There are around 130 species of coffee plant - but not all taste good. In Sierra Leone, scientists from Kew helped to identify one candidate, stenophylla, growing in the wild.
Two other coffee species also show promise for commercial cultivation in a changing climate - liberica and eugenioides, which "has low yields and very small beans, but it has an amazing taste," according to Davis.