In a book about the dawn chorus, about songbirds and birdsong, the Peregrine Falcon might not be the obvious place to start, but bear with me. For one thing, you don’t have to ponder for long the question ‘What is a songbird?’ or ‘What combines to make the dawn chorus?’ to realise that these are broader concepts than they may have appeared at first glance. All birds are songbirds. Eit…