Grey Nurse Shark jaw (Carcharias taurus).
Image: Benjamin Healley
Source: Museum Victoria
Question: Are there any fish that do not have bones?
Answer: All fishes have a skeleton of some kind to give support to their bodies.
A number of fish groups have fully cartilaginous skeletons – cartilage is a firm, elastic, flexible type of connective tissue of a translucent whitish or yellowish colour.
The primitive lampreys and hagfishes have very primitive skeletons, as do sharks, rays and chimaeras.
All other fishes have ‘bony’ skeletons, although the skeletons of some deep-sea fishes are poorly ossified (hardened like or into bone).