Dimetrodon Spine Sail Fragments protomammal and a piece of a

and a piece of a 2004 Athens Olympic Relay Torch

and patterns vary widely

and axes all fall under the designation of celt

In any case

This specimen is a fossil bone fragment of the Apatosaurus

Dimetrodon Spine Sail Fragments protomammal and a piece of aWith 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.