Return of the rhino: can we bring the northern white back from extinction?

An enthralling project to save the northern white rhino is raising challenging questions as scientists debate the ethics of de-extinction When Dr Natalie Cooper, a scientist at the Natural History Museum, met Sudan, the last surviving northern white male rhino, in Kenya before he died aged 45, she understandably feared the subspecies' extinction was certain - mostly due to poaching fuelled by human greed for the prized horn. "The sense of enormity when staring extinction right in the eye is diff...