Hypsodonty

Hypsodonty is a dental trait characterized by high-crowned teeth. In hypsodont teeth, the enamel extends well below the cemento-enamel junction, and a substantial portion of the crown remains beneath the gumline even as wear occurs. As wear wears down the occlusal surface, the tooth continues to erupt to maintain functional height. This contrasts with brachydont dentition, where crowns are relatively low and eruption is limited after eruption. A related category, hypselodont, describes teeth that grow continuously and lack a true root.

Hypsodonty is common in herbivorous mammals, particularly grazing ungulates such as horses, cattle, sheep, and deer, where abrasive grasses and grit create heavy wear. It also occurs in some rodent and lagomorph species and in other groups with similar diets. The degree of hypsodonty varies among species and can reflect dietary strategy, habitat, and life history.

In paleontology and comparative anatomy, hypsodonty is used to infer dietary habits and environmental conditions of extinct species. High-crowned teeth tend to be associated with processing fibrous plant material, while brachydont teeth are more typical of species with softer or mixed diets. The trait is studied to understand feeding ecology, evolution of dentition, and ecological pressures across lineages.

Developmentally, hypsodont teeth usually exhibit extended eruptive growth and a thick enamel cap. Researchers compare relative crown height and root formation across taxa to interpret functional and ecological significance in both living and fossil mammals.