Matthew Cobb on how we detect smells

It’s been estimated that humans are capable of detecting a trillion different smells. How is this possible when we have just 400 types of olfactory receptors located in the bridge of our nose? Matthew Cobb has spent many years studying maggots hoping to get to bottom of this problem. He spent several years studying the flirting rituals of fruit flies in Sheffield before moving to France to study at the world centre for fly research, not far from Paris. There are, of course, a lot of differences between maggots and humans but our olfactory systems have a lot in common.Producer: Anna Buckley