02 – Loss of the canine honing complex
7.0 to 6.0 million years ago
Many primates evolved a dental arrangement of large, pointed canine teeth that are used for defensive or aggressive display. These canine teeth sharpen against the edge of their neighboring tooth, the first premolar, and this arrangement is referred to as the canine honing complex. Hominins have lost this trait and have evolved much smaller canines than most other primates have. This anatomical change is thought to reflect a change in social structure with canines no longer acting as defensive weapons against group members. Modern human’s canine teeth are generally small and not very pointed. Read more about other critical adaptations and diet and feeding behavior.
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Environmental and Climate Changes
Global cooling and expansion of grasslands 8.0 to 5.0 Ma