The cranium of MH1, the juvenile male Australopithecus sediba, was investigated by high-quality synchrotron scanning, as reported in Science in September 2011. The reconstructed brain capacity is about 420 cubic centimeters, higher than Australopithecus africanus Taung baby (ca 406 cm) but much smaller than the Au. africanus species overall average, of circa 485 cc.
Modern human skulls have a cranial capacity of some 1320 cc. Scholars examining the skull suggest that the orbitofrontal region of the brain suggests some foreshadowing of the development of human frontal lobes.
Sources
Berger LR, De Ruiter DJ, Churchill SE, Schmid P, Carlson KJ, Dirks PHGM, and Kibii JM. 2010. Australopithecus sediba: A New Species of Homo-Like Australopith from South Africa. Science 238:195-204.
Carlson KJ, Stout D, Jashashvili T, De Ruiter DJ, Tafforeau P, Carlson K, and Berger LR. 2011. The endocast of MH1, Australopithecus sediba. Science 333:1402-1406.
