A shark tooth is not a generic object. Its shape was determined by where in the jaw it sat and what role it played in feeding. Identifying the position of a single isolated tooth is one of the foundational skills of a collector. Once you can read position, the rest of the catalog makes more sense.
The Four Positions
Most shark species follow a consistent four-zone arrangement: anterior, lateral, posterior, and symphyseal. Each zone shapes its teeth toward a specific function.
Anterior Teeth
Anteriors sit at the front of the jaw and do the work of grasping prey. They are the tallest, most symmetrical, and most photogenic teeth in the dentition. In a great white, the upper anterior teeth can reach the largest sizes the species produces. Symmetry between the mesial (front) and distal (back) cutting edges is the visual signature: a near-isoceles silhouette with a centered tip.
Lateral Teeth
Laterals sit immediately behind the anteriors and do the work of cutting. The crown leans toward the back of the jaw, the distal edge is shorter than the mesial edge, and the silhouette becomes asymmetrical. Laterals are typically smaller than anteriors of the same individual but read as more aggressive in profile.
Posterior Teeth
Posteriors sit at the back of the jaw and crush. The crown is short and broad relative to the root. In some species the posterior teeth lose their serrations almost entirely. Posteriors are the least photogenic but they are the diagnostic signature of a complete dentition; a jaw without posteriors is incomplete.
Symphyseal Teeth
Symphyseals sit at the symphysis, the centerline of the lower jaw. They are typically small, narrow, and somewhat irregular. Symphyseals are the rarest position in isolated tooth catalogs because they are smaller and less commonly shed during feeding events.
Identifying Position from a Single Tooth
Three diagnostic checks: 1. Compare the mesial edge to the distal edge. If they are nearly mirrored, it’s an anterior. If the distal edge is markedly shorter, it’s a lateral. 2. Look at the crown-to-root ratio. Anteriors are tall; posteriors are short and broad. 3. Check the lean. A tooth that points straight up is anterior; a tooth that leans is lateral or posterior.
Upper vs. Lower
Within each position, upper jaw teeth are typically larger and more dramatically serrated than their lower jaw counterparts. The lower jaw teeth in great whites also tend to have a slimmer profile.
Why It Matters
Position affects price. It affects display value (anteriors photograph best). It affects authenticity assessment (a tooth labeled as anterior but with the lean of a lateral is either misidentified or the seller is unfamiliar with the species). Knowing how to read position is one of the simplest ways to upgrade your eye.