barry marshall. barry's groundbreaking research turned the world's understanding of stomach cancer on its head and won him the nobel prize in medicine. barry is a complete science legend. today barry is hunting a nasty microbe called helicobacter. this bacteria infects the guts of animals and makes them sick. - there are about 30 different kinds of helicobacter. so one of the things i'm planning to do today is go around, get some animal scat. so most of it's kangaroo. - [julia] oh, i'm looking forward to seeing the whole process. i've never seen a kangaroo, i don't think. barry is trying to figure out where helicobacter came from by searching for it in a wide range of animals. - you see those big grassy areas over there. that's where the kangaroos might be hanging out. - [julia] kangaroo! - [barry] so now you've seen one. - [julia] seen one! - [barry] well, i think i can see one. - [julia] oh yeah! - there, there, it looks like it's good enough. - [julia] by analyzing kangaroo feces, barry can get a s