 Linguist Christopher Ehret suggests that around the fifth and sixth centuries BC, the speakers of the Southern Nilotic languages split into two major divisions - the proto-Kalenjin and the proto-Datooga.The former took shape among those residing to the north of the Mau range while the latter took shape among sections that moved into the Mara and Loita plains south of the western highlands.There are at least seven Datooga tribes