Hominid Ancestry
In the Afar desert of Ethiopia, paleoanthropologists have been piecing together hominid history. The newest finds are from an early member of the Australopithecus species, Australopithecus anamensis, and are dated at about 4.1 million years old. Paleoanthropologists believe that Australopithecus evolved from Ardipithecus.
The significance of this finding is that this 4.1 million year old Au. anamensis provides a link for Australopithecines to Ardipithecus. The seven known species of Australopithecus range from 4.2 to 1.2 million years ago; the most recent species Au. bosei co-existed with Homo. The ancestral Ardipithecus ranges from 4.4-7 million years ago. The most recent fossils were found in sediment on top of layers containing Ardipithecus fossils, and underneath Australopithecus afarensis fossils. Based on other fossils in the sediment layers scientists can tell what kind of habitat Au. anamensis lived in, which helps scientist understand how it lived.
Links:
University of California, Berkeley
CNN
Resources for exploring human evolution:
PBS
Becoming Human