Nell - And this is a little bit sad because it's the kind of crushing of an urban legend. People did use to think that pigeons actually had magnetic beaks and that this acted as a sort of compass, allowing them to do these amazing feats of navigation that we hear about. What this research in Nature has shown is that in fact this isn't true and it's a bit of shame really. They do, it turns out have cells in their beaks which are filled with iron and that was clearly the clue that led people to think that perhaps this was acting as a kind of compass. But in fact, they found that these are macrophage cells. They're white blood cells. So, there's no way they could be sending messages to the brain because they're not just designed to do that sort of thing, these cells. So, we still got to find a way, how are these pigeons navigating?
Kat - I love the quote from the researcher David Keays. He said, "We've put the cat among the pigeons now."
Nell - He did. Just couldn't resist that clearly.