Feeds

Is the human skull made up of one bone or two?

Soft spots explained

Build a business case: developing custom apps

Also in this week's column:

Is the human skull made up of one bone or two?

Asked by Jill Maynard of Greenacre, New South Wales, Australia

It surprises many to learn that the human skull is not one solid bone as is usually thought. Nor does it consist of just two bones---the top of the head and everything underneath. The skull (cranium) is actually composed of (count them!) twenty-two separate bones. There are eight cranial bones around the brain and fourteen facial and jaw bones in the human skull. Just one of these bones moves - the jaw bone (mandible). In infants and very small children, the cranial bones are disconnected segments held together by connective tissue stripes called sutures. At certain sites, these sutures are especially weak, creating the so-called “soft spots” (fontanels) in an infant’s head. The most prominent of these is a little way up from the infant’s forehead. When growing is complete, the bones of the skull fuse together along the suture lines. These unions contain small amounts of fibrous connective tissue similar to those of the joints of arms and legs. Although the skull may structurally appear to be one piece when fully developed, it is still composed of separate bones. Many fossil skeletal remains that anthropologists find often appear to have cracked or broken skulls. But these skulls are actually just missing some of their pieces. The softer connective tissue having decomposed, little support is left between the individual pieces in the skull. This causes them to fall out and perhaps get left behind over thousands and thousands of years. Has anyone seen my...? Then again, let’s not get a head of ourselves.

Stephen Juan, Ph.D. is an anthropologist at the University of Sydney. Email your Odd Body questions to s.juan@edfac.usyd.edu.au

Boost IT visibility and business value

More from The Register

next story
Just TWO climate committee MPs contradict IPCC: The two with SCIENCE degrees
'Greenhouse effect is real, but as for the rest of it ...'
Asteroid's DINO KILLING SPREE just bad luck – boffins
Sauricide WASN'T inevitable, reckon scientists
Brit amateur payload set to complete full circle around PLANET EARTH
Ultralight solar radio tracker in glorious 25,000km almost-space odyssey
Boffins spot weirder quantum capers as neutrons take the high road, spin takes the low
Cheshire cat effect see neutrons and their properties walk different paths
NASA Mars rover FINALLY equals 1973 Soviet benchmark
Yet to surpass ancient Greek one, however
Famous 'Dish' radio telescope to be emptied in budget crisis: CSIRO
Radio astronomy suffering to protect Square Kilometre Array
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
The Essential Guide to IT Transformation
ServiceNow discusses three IT transformations that can help CIO's automate IT services to transform IT and the enterprise.
Maximize storage efficiency across the enterprise
The HP StoreOnce backup solution offers highly flexible, centrally managed, and highly efficient data protection for any enterprise.