FOSSIL ELEPHANTOIDS, AWASH PALEOLAKE BASINS, AND THE AFAR TRIPLE JUNCTION, ETHIOPIA

The most diverse collection of fossil elephantoids from a single area, are contained in the 1-km-thick hominid-bearing Awash Group. These de posits range from late Miocene to Holocene in age and are found in the Awash Valley of the Afar Depression, Ethiopia. Uniquely, the Afar ele phantoids inhabited a series of internal lake basins splayed out acros s an evolving, subaerial triple junction created by the separation of the African, East African and Arabian plates. The spatial and temporal distribution of elephantoids in these basins demonstrates that these animals were progressively drawn into the central Afar with the diverg ence of the three plates. As such, the elephantoids moved from the hig her margins of the East African and African plates to the depressed lo wlands of the triple junction, where subsiding and migrating lake basi ns served as ideal habitats for large herbivores with high water requi rements. This pattern of migration serves as a model for the migration of animals into intercontinental areas and for their dispersal across plate boundaries.