Palms provide many basic necessities and are collectively one of the most important plants families after grasses and legumes. In 2007 and extraordinary new find came to light when a French plantation manager in Madagascar, came across a new species of palm tree 18metres high and with a 5m leaf span - visible from Google Earth. The palm family continues to grow at a rapid rate As new species make themselves known to science it's becoming vital to appreciate their potential uses. Discoveries are also helping to shed light on the "palm tree of life".

Professor Kathy Willis meets Head of Palms at Kew, Bill Baker, to examine how new technology such as DNA sequencing has come to provide an amazing evolutionary record of palms over timescales greater than the fossil record can offer. Crucially, it's beginning to show when the diversification of palms began. In doing so, the genetic analysis is beginning to rewrite our understanding of the origins of the rainforest and looking to favour Alfred Russel Wallace's overlooked "museum model " of the evolution of ancient rainforests.

With additional contributions from head of the Kew Palm House Scott Taylor, and former Head of Palms at Kew, John Dransfield

Producer Adrian Washbourne.