Scientists identified an amazing concentration of species in the Eastern Arc Mountains of Tanzania and Kenya, with unusual characteristics:
"The wild areas of the Eastern Arc Mountains are pockets of Eden--the last remaining safe havens for over 1000 plants and animals found nowhere else on Earth and some with ancient lineages stretching back in time over millions of years," said Dr. Neil Burgess, lead author of the two studies and Eastern Arc expert, World Wildlife Fund and University of Cambridge. "Side by side, these species and their human neighbors struggle for survival as more and more people need more and more farmland for food. ..."
The studies point out another unusual characteristic of the species in the Eastern Arc Mountains: a number of them are genetically ancient. DNA analysis of forest birds indicates that some species have lineages stretching back 25 million years and some are most strongly related to birds in Southeast Asia than birds in Africa. Some plants and animals--like tiny little shrews with elephant-like trunks known as elephant shrews and nocturnal primates with large eyes known as bushbabies--are thought to have evolved early in the species lineage, known as "primitive" or "ancient relic lineages."