It's not all monkey business in the villages of Zanzibar Island in Tanzania, Africa. The local red colobuses have serious health issues. Their food sources have declined to just a fraction of the many different types of plants normally found in the outlying dense forests. This has resulted in high levels of toxins accumulating in their bodies. But these are no ordinary primates. They've adapted quite well with an unappetizing addition to their daily diet that helps flush away the deadly toxins.