Most groups of wildlife can be described as a flock or a herd, a swarm or a shoal – but where is the fun in stopping there? From an army of ants to a dazzle of zebras, an exultation of larks to a murder of crows, the English language is brimming with weird and wonderful collective nouns to describe groups of animals and birds. Michael Rosen talks to Matt Sewell, author of 'A Charm of Goldfinches', about some of the more obscure examples that have made their way into common usage as collective nouns for creatures of the land, the sea and the air... Produced for BBC Audio Bristol by Becky Ripley