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Children belonging to our earlier ancestors did not develop as quickly as modern humans, researchers have found.

Researchers studied the Taung Child, a 3.3 million year old skull discovered 90 years ago in South Africa.

They found the Taung Child, known as Australopithecus africanus, was not like an ordinary toddler of today - it didn't experience a spurt in brain growth in its first few months, as modern babies do, making it less human-like than previously thought. 

The first reconstruction of the Taung Child, a 3.3 million year old human ancestor, found it didn't experience a spurt in brain growth in its first few months, as modern babies do, making it less human-like than previously thought.

Their findings disprove the idea that this early hominin shows infant brain development in the prefrontal region similar to that of modern humans.

The Taung Child has historical and scientific importance in the fossil record as the first and best example of early hominin brain evolution, and theories have been put forward that it exhibits key cranial adaptations found in modern human infants and toddlers.  

By subjecting the skull of the first australopith discovered to ta CT scanner, researchers are now casting doubt on theories that Australopithecus africanus shows the same cranial adaptations found in modern human infants and toddlers.

It is the first time that such a high-resolution scan has been taken of the fossil.

This disproves current support for the idea that this early hominin shows infant brain development in the prefrontal region similar to that of modern humans. 

THE TAUNG CHILD

Killed by an eagle? The Taung Child's skull

Found in south Africa, the roughly 3 million-year-old fossil is thought to have belonged to a 3 to 4-year-old.

The Taung Child has historical and scientific importance in the fossil record as the first and best example of early hominin brain evolution.

When this 3-year-old child's skull was found in 1924, it was among the first early human fossils to be found in Africa - and the first early human fossil discovery to draw major attention to this region as a place of origin of the human family tree.

The Taung Child's first molars had only just begun to erupt through the gum and become visible as teeth, indicating that the fossilized jaw belongs to a child. 

Closer analysis of dental development, crown formation, and root length has estimated the child's age at death at 3.3 years. 

The Taung Child is thought have been attacked and killed by an eagle. 

Scientists suspect an eagle killed the Taung Child because puncture marks were found at the bottom of the 3-year-old's eye sockets

To test the ancientness of this evolutionary adaptation, Dr Kristian J. Carlson at the Evolutionary Studies Institute at the University of the Witwatersrand, and colleagues performed a virtual dissection of the skull.

'A recent study has described the roughly 3 million-year-old fossil, thought to have belonged to a 3 to 4-year-old, as having a persistent metopic suture and open anterior fontanelle, two features that facilitate post-natal brain growth in human infants when their disappearance is delayed,' said Carlson.

Dr. Kristian Carlson in the Microfocus X-ray Computed Tomography facility at Wits University with the skull

'Results of the new study show that there is still no evidence for this kind of skull adaptation that evolved before Homo, nor is there evidence for a link between such skull characteristics and the proposed accompanying early prefrontal lobe expansion,' Carlson said.