No soft spot on 3-million-year-old child skull: study
August 27, 2014, 12:04 am TWN
WASHINGTON--A three-million-year-old child's skull uncovered in South Africa has no signs of the kind of soft spot that would be seen in human children with larger brains, a study said Monday.
The findings are the latest contribution to long-running debate over whether the Taung Child fossil may have represented the earliest signs of a fusing skull.
Babies today are born with a number of plates in their skull that are loosely joined, forming soft spots that eventually come together.
Scientists believe we evolved this trait to accommodate our growing brain, which since the age of the Neanderthals has been larger than the brains of earlier human ancestors.
The Taung Child was uncovered 90 years ago in South Africa and some researchers thought the skull showed the first signs of such skull adaptation in a hominid known as Australopithecus africanus, which lived 2.1-3.3 million years ago.
For the latest study, researchers at the University of the Witwatersrand, Columbia University and Florida Atlantic University used high-resolution computed tomography to look at each layer of the skull.
"According to the authors, the results as well as comparisons with the hominin fossil record and chimpanzee variation do not support the hypothesis that the features evolved in A. africanus or early Homo hominins," said the study in the Proceedings of the National Academy of Sciences.