Dimetrodon Spine Sail Fragments

With a fearsome jaw and reptilian appearance, Dimetrodon is often mistaken for a dinosaur. However, this family of Early Permian Period species falls into a disparate taxonomic clade known as synapsids which includes mammals. This specimen is a fossil fragment of the Dimetrodon's iconic spine. The purpose of the spine sail is unknown, though speculation ranges from thermoregulation and locomotion.