Method of micro-sampling human dentine collagen for stable isotope analysis

Area of Science:

• Paleoanthropology and Bioarchaeology
• Isotope Geochemistry
• Human Biology

Background:

• Dentine isotope analysis (δ¹³ C, δ¹⁵ N) tracks diet and stress during tooth formation.
• Current 1mm sampling methods yield 6-9 month resolution, averaging short-term changes.
• Improved temporal resolution is needed for detailed life history reconstruction.

Purpose of the Study:

• To introduce and validate a novel MicroMill-assisted sampling method for dentine collagen.
• To achieve higher temporal resolution in stable isotope analysis from human dentine.
• To enhance the study of short-term dietary and physiological variations.

Main Methods:

• Utilized a NewWave MicroMill for precise sampling of demineralised dentine.
• Collected 0.35mm increments along dentine growth lines in human third molars.
• Compared results with traditional 1mm incremental sampling methods.

Main Results:

• The MicroMill method achieved a temporal resolution of 2-4 months per increment.
• Demonstrated increased temporal resolution for δ¹³ C and δ¹⁵ N isotopic data.
• Reduced averaging of isotope ratios compared to previous techniques.

Conclusions:

• The MicroMill method offers enhanced temporal resolution for dietary reconstruction and stress analysis.
• Enables the study of potentially seasonal physiological changes with greater accuracy.
• Minimizes attenuation of isotopic values, providing more reliable data.