By Maina Kiarie
Australopithecus sediba lived in Southern Africa (South Africa) between 1.95 and 1.78 million years ago. Australopithecus sediba has more derived features that are also found in the genus Homo than other australopithecines, linking it closely with our own genus. These links indicate that Au. sediba may reveal information about the origins and ancestor of the genus Homo. Discovered in 2008, by Matthew Berger, the 9 year old son of paleoanthropologist Lee Berger from the University of Witwatersrand, at the site of Malapa, South Africa, Australopithecus sediba has a skull that shows relatively small premolars and molars, and facial features that are similar to those in Homo. However, despite these changes in the pelvis and skull, other parts of Au. sediba skeleton shows a body similar to that of other australopithecines with long upper limbs and a small cranial capacity. The combination of primitive and derived traits in Australopithecus sediba shows part of the transition from a form adapted to partial arboreality (living in trees/tree climbing) to one primarily adapted to bipedal walking. The fossils also show that changes in the pelvis and the dentition (teeth & jaw structure) occurred before changes in limb proportions or cranial (brain) capacity.
A skeleton of a juvenile male about 12-13 years old was 1.3 metres (4 ft 3 inches) tall. Sediba had small bodies with long arms enabling them to climb and live on trees with ease.
Recent articles published by the Lee Bergers team show that Australopithecus sediba had remarkably human like hands which suggest that the species had a precision grip, capable of making and using tools.
A. sediba’s brain was similar to that of modern humans yet was surprisingly small—only about a quarter the size of a modern human brain, or a little larger than the brain of a chimpanzee.