A recent study compared the skulls of modern day people, and older
skulls. They came to some unexpected results: the shape of the human
skull has changed considerably in the six or seven hundred years
between the modern and medieval samples. It would appear that our
skulls, and most likely our brains, are getting selectively bigger.
Modern people possess less prominent features but higher foreheads than our medieval ancestors.
Writing in the British Dental Journal, the team took careful measurements of groups of skulls spanning across 30 generations.
The scientists said the differences between past and present skull shapes were "striking".
Plague victims
The team used radiographic films of skulls to record extensive measurements taken by a computer.
They looked at 30 skulls dating from the mid-14th
Century. They had come from the unlucky victims of the plague. The
skulls had been excavated from plague pits in the 1980s in London.
Another 54 skulls examined by the team were recovered
from the wreck of the Mary Rose which sank off the south coast of
England in 1545.
All the skulls were compared with 31 recent orthodontic records from the School of Dentistry in Birmingham.
The two principal differences discovered were that our ancestors had
more prominent features, but their cranial vault – the distance
measured from the eyes to the top of the skull – was smaller.
Dr Peter Rock, lead author of the study and director of
orthodontistry at Birmingham University, told the BBC News website:
"The astonishing finding is the increased cranial vault heights.
"The increase is very considerable. For example, the
vault height of the plague skulls were 80mm, and the modern ones were
95mm – that’s in the order of 20% bigger, which is really rather a
lot."
He suggests that the increase in size may be due to an increase in mental capacity over the ages.
Repatriating bones
The study of human remains has previously fallen into
controversy, and a report commissioned by the UK government called for
human remains to be repatriated where possible.
The ancient skulls used in this study, from which the
radiographic films were taken, have either been reburied or are now
housed in museums.
Professor Robert Foley is director of the Leverhulme
Centre for Evolutionary Studies at Cambridge University, and sat on a
government working group which has drawn up guidelines on working with
human remains.
"The study of human remains can provide vital
information about our past. There is a huge interest in our biological
past – both from an evolutionary and a historical point of view – and
research into human bones can tell us a great deal," he said.
"This new research shows how bones, and even the records
of bones, can provide more knowledge to the scientific community, and
ultimately the public."
