The Head and Appendicular Skeletons of Shark

By LaToya Riley and Kumiko Kojima

Phylum: Chordata

Subphylum: Elasmobranchii

Class: Chondricthyes

Order: Squaliformes

Family: Squalidae

Genus: Squalus

Species: Acanthias

In the study of vertebrate anatomy sharks offer a deeper look into the evolutionary past- a glimpse of aquatic life and gills, long before terrestrial living and lungs.  Though their structure is less complex than that of mammals, sharks are still well adapted to effectively function in their surroundings. 

The primary focus of this site is to examine how form relates to function- in particular, the workings of the head and appendicular  skeletons.

The specimen of focus will be Squalus acanthias, otherwise known as the dogfish.

The head and appendicular skeletons together form the axial skeleton of Squalus.  Being a member of the Class Chondricthyes suggest that the entire body skeleton is formed of cartilage.  This provides protection for internal organs as well as allows for added maneuverability and flexibility that would be otherwise inhibited by  a skeleton made of bone.  


Head Skeleton                                 Appendicular Skeleton