Julio Rozas and Paul Librado, researchers at the University of Barcelona (UB) and the Institute for Biodiversity Research of the UB (IRBio), participating in an international consortium to sequence first the nuclear genome of the coffee species Coffea canephora. The study published in the journal 'Science' gives new clues about the evolution of caffeine. The results show that the genes responsible for caffeine evolved independently of genes with similar functions in tea or cocoa.