Rats represent the worst of us or at least, that's what we tell ourselves. They are rapacious, over-sexed, pestilent and, on occasion, cannibalistic. But, as with all 'vermin', rats are in fact a mirror species, reflecting back to us our worst excesses. They are also a creature to which we owe a lot. Arguably no other animal has done more for the advance of human medicine than the rat. In Stowaway, Joe Shute unpicks this complex relationship between...