Lee R. Berger holds the cranium of Australopithecus sediba. He is credited of the finding of these two fossils.
As you may not know, a new Australopithecus specie has been found! This specie is called Australopithecus sediba and the two fossils that were found were dated to be around 2 million years old. These two fossils are of an adult woman and a young adolescent male (around 10 to 13 years for the young boy) - some suggest that it was a mother and a son.
Australopithecus sediba is younger than Lucy and lived around the same time as Homo habilis - some think that sediba is a transitional fossil between Lucy and Homo erectus, and that Homo habilis may not be our ancestor! Others say Homo habilis is one, and that sediba is an evolutionary dead end (no species today are descended from it).
These two fossils were found in a cave of Malapa, 40 km near Johannesburg, Africa. What's amazing about these fossils is that it debunks the preconceived notion that the first brain first grew in size and then "reorganized" itself. Instead, from the evidence of these two new fossils, we can see how parts of the brain were "reorganizing" for long-term planning, reasoning, and multitasking, while the vault capacity of the brain itself was only 420 cubic centimeters. Its height was similar to that of a chimpanzee (1.3 m tall). Additionally, although people once thought that the brain size grew first, and then the pelvis size grew (to compensate for the big heads popping out of the mother's womb), the pelvis size was the first to grow, since the female Australopithecus sediba found had a pelvis similar to that of a modern human's.
The fossils were too old to be dated by themselves, so scientists tested the calcified sediments that kept the fossils preserved (which would determine the ages before and after the fossils themselves, e.g. determine the layers of earth near the fossils, a.k.a. stratigraphy.) Then, uranium-lead dating and paleo-magnetic dating precisely determines the age of the fossils (1.977 years ago, rounded to 2 million years).
A video about Australopithecus sediba.
REFERENCES
Waterloo Record - Friday, September 9 2011 (Mrs. R.C. gave me it)
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