Where do camels come from? In the Arab world may seem the obvious answer. But they are relative newcomers there. They evolved in North America and retain their greatest diversity in South America, while the only wild dromedaries are in Australia.
This is a classic example of the contradictions of 'native' and 'invasive' species, a hot issue right now as the flip-side of biodiversity. Do we need to fear invaders? Can we control them? Do we choose the right targets? And are the natives always good guys?
Thompson puts forward a fascinating array of narratives to explore this crucial question.