Chew on this, Nutcracker man

ONCE he was our lantern-jawed relative who had a set of gnashers that could chew through anything.

In fact, his fat molars and strong jaw earned him the nickname the Nutcracker Man.

The story went that this distant relative of humans who lived 1.8 million years ago used his teeth and jaw to crunch on a diet of nuts, hardened tubers and seeds.

But now it appears Nutcracker Man was not all he was cracked up to be.

An analysis of 20 000 teeth found in museum collections from around the world, including South Africa, has found Nutcracker Man or Paranthropus boisei, didn’t have a taste for the hard things in life, but probably feasted on soft fruits and plants.

Nutcracker Man may be a layman’s term but to scientists he is simply OH5, the numbered skull that famed palaeoanthropologist Mary Leakey found at Olduvai Gorge in Tanzania in 1959.

At the time it was thought that P. boisei was a direct ancestor of humans.

Now it is believed the Paranthropus branch of the human tree was separate and withered away after these hominins became extinct.

Initially his big teeth and jaw had palaeoanthropologists suspecting for 60 years he had a hard tack diet.

But new research is adding more evidence that Nutcracker man and his close relative in South Africa Paranthropus robustus did not.

Dr Ian Towle, a biological anthropologist at the University of Otago in New Zealand with Dr Carolina Loch, of the Faculty of Dentistry began a forensic investigation of hominid and human teeth.

“By individually studying each tooth and recording the position and size of any tooth fractures, we show tooth chipping does not support regular hard food eating in Paranthropus robustus, therefore potentially putting an end to the argument that this group as a whole were hard food eaters,” he said.

The study was published in the Journal of Human Evolution.

It is a finding, believes Towle, that challenges our understanding of human evolution and with it all its dietary and behavioural changes.

“The results are surprising, with human fossils so far studied – those in our own genus Homo – showing extremely high rates of tooth fractures, similar to living hard object eating primates, yet Paranthropus show extremely low levels of fracture, similar to primates that eat soft fruits or leaves,” he added.

This is not the first time palaeoanthropologists have found evidence that Nutcracker Man and other Paranthropus species favoured soft food.

In 2008 several South African scientists delved into the Nutcracker Man’s diet after they drilled into one of his teeth and extracted enamel the size of a grain of sugar.

Through carbon isotope analysis, the scientists were able to trace the changes in the ratios of two carbon isotopes that occur in the food change.