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All of us have the same basic skeletal structures (206 bones in the adult skeleton) that identify us as human. But, between the young and old, male and female, and among ancestral groups, there are recognizable skeletal variations.

Long, short, flat, or irregular—a bone's external shape and internal structure suits its job in the body. Bones provide attachment sites for muscles and let us move by means of joints. Bones protect our internal organs—especially the brain, spinal cord, heart, and lungs. Bone supports us in life, and it can last long after death.

Sliding caliper & femur.   

   Techniques and Tools of the Trade

Learn the standard techniques used to measure and characterize bones.


   An Inside Look at Bone

Discover what lies within your own bones.

arthritis on spine    

   Young or Old?

Skeletons record a person's age in several ways.

male pelvis and female pelvis    

   Male or Female?

Size and sturdiness give us some clues.


male skull of European origin    


Despite variability, our bones carry clues to our ancestry.


does this bone belong to a human?    

   Human or Non-Human?

Can you tell the difference between human and non-human bones?




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