Pollen detective: Forensics’ secret weapon

Professor Patricia Wiltshire is a leading forensic ecologist and botanist. For the last 25 years she has helped solve some of the UK’s most serious crimes including a number of the country's most high-profile murder cases. To do this she uses her vast knowledge of plant science, finding clues to the crimes in microscopic grains of pollen and spores. She’s written a book called Traces: Every body leaves a mark. Presenter: Emily Webb Producer: Thomas Harding Assinder Image: pollen under high-powered photomicrographic magnification Credit: BSIP/Universal Images Group via Getty Images