In a broad arc running 500 miles down the eastern side of Tanzania are seven ancient mountain ranges. This Eastern Arc, as it is known, is the first barrier in East Africa to the moist trade winds of the Indian Ocean. From the rising air fall torrents of warm rain in thunderous storms and lightning displays, and endless weeks of mist and cloud. This has been a pattern for tens of millions of years, creating the oldest rain forests in Africa and amongst the oldest in the world.
These forested islands are surrounded by seas of drier savannas, and their isolation has led to the evolution of the most unique and varied plant and animal life in all of Africa. The fascinating thing about them is how unexplored they are. A completely new species of monkey, the Sanje mangabey was discovered as recently as 1979, and a new species of francolin (partridge family) was rst discovered by scientists in 1992 – the Udzungwa Forest Francolin.
