Most people associate think of bird poop as an annoyance -- it can gunk up sidewalks and windshields, and, occasionally, even splat on an unlucky person walking by. But in the late 1800s, guano was a hugely important resource. In today's episode, Ben, Noel and Max take a closer look at the 'white gold' of guano... and how it led to one of 19th-century South America's deadliest wars.