Bone Diagenesis

Human Skeletal Analysis Pitt 24

bone diagenesis

Process by which there are different chemical and biological process that degenerate bone 

Microbial bioerosion

biological degradation of collagen and hydroxyapatite

Invasive microorganisms degrade bone proteins

micro-foci of destruction

micro-foci of destruction

characteristic tunnels in the internal microstructure of the bone

Wedl tunneling 

This is associated with the blue-green algae destruction in aquatic environments

Non-wedl MFD tunneling

Found in archaeological bone from terrestrial contexts

Methods to find microbial erosion 

• Thin section light microscopy

• Scanning electron microscopy

• Micro CT scans

Thin section light microscopy

Thin cross-section of bone – cutting directly (or grinding)

Cross-section is mounted on a slide and examined

Scanning electron microscopy

More expensive

Greater resolution

Also destructive - thicker cuts of bone are taken

Micro CT scans

Non-invasive!

Allow us to look at whole bone samples

But more expensive 

process by which enteric gut microbiome has access to bone

• Death

• Mucosal membranes that confine enteric bacteria begin to break down

• Bacteria migrate via the circulatory system within a few hours after death

• Access to bone via the haversian system 

Infants and gut microbiome 

Prenatal infant gut is acquired via the placenta from the mother – less diverse

Microbiome is formed after birth through feeding and contact with the external environment

how knowledge of the gut microbiome can help us to distinguish between stillborn and live-birth infants

Bacterial bioerosion in all live-born individuals

No signs of bacterial attach in buried or unburied stillborn carcasses

osteolytic microbiome emerges around___

the point of birth

When does osteolytic aspects of the microbiome develop?

Exposure to mother’s vaginal and intestinal microbiota feces at point of birth

breastfeeding