After warning us that Rio has a hidden killer, the dengue virus, carried by mosquitoes. Mike takes one of the city's more unusual guided tours - through a favela, or slum.
In the mangrove swamps of Borneo, Mike checks out the claws of a mangrove crab and the healing...
(04:54)Mike visits the Gomantong Caves in Borneo, full of a million bats and a hundred foot pile of bat...
(03:12)