Beyond the Map: Enamel Distribution Characterized from 3D Dental Topography

Area of Science:

• Paleoanthropology
• Primate Anatomy
• Evolutionary Biology

Background:

• Enamel thickness is crucial for tooth survival, especially in primates consuming hard or stress-limited foods.
• Previous research suggested thicker enamel and uneven distribution in durophagous (hard-object feeding) primates, but quantitative methods were lacking.

Purpose of the Study:

• To develop and apply a quantitative methodology for characterizing enamel 3D distribution in anthropoid primates.
• To test the hypothesis that thick enamel is more unevenly distributed in durophagous species.

Main Methods:

• Microcomputed tomography (micro-CT) scanning of upper second molars from 32 anthropoid primate species.
• Computation of 3D average and relative enamel thickness using volumetric reconstruction.
• Development of pachymetric profiles and use of 3D dental topography to assess enamel distribution evenness.

Main Results:

• Two methods for estimating enamel thickness yielded different results.
• Pachymetric profiles and topographic maps showed thick enamel is not significantly more unevenly distributed in most durophagous primates.
• An exception was found in Cercopithecidae, where durophagous species exhibited uneven thick enamel distribution.

Conclusions:

• The distribution patterns of thick enamel vary significantly across anthropoid primates.
• Different durophagous strategies may have evolved in response to selective pressures from stress-limited diets.
• Further research is needed to fully understand the functional implications of enamel distribution in primate feeding adaptations.