In a reverse hierarchy, the conceptual pyramid of authority is turned upside-down, so that the apex is at the bottom and the base is at the top. This model represents the idea that members of the higher rankings are responsible for the members of the lower rankings.
Along the sides of the body is a light-colored horizontal stripe called the lateral line. The line is made up of a series of tiny pores that lead to receptors that are sensitive to the mechanical movement of water and sudden changes of pressure.The spiny dogfish has a double dorsal fin.The anterior dorsal fin is larger than the posterior dorsal fin.The spiny dogfish has the presence two spines, one immediately in front of each dorsal fin. The spines carry a poison secreted by glands at their base.he spiny dogfish has a double dorsal fin. The anterior dorsal fin is larger than the posterior dorsal fin. The spiny dogfish has the presence two spines, one immediately in front of each dorsal fin. The spines carry a poison secreted by glands at their base.
Unique Characteristics. 1.The skeleton of the cartilaginous fish is out of a flexible bone-cartilage. The skeleton does not have any bone. 2.These fish have dorsal fins, an anal fin, a pair of ventral fins and a single caudal fin.he bony fish have a pair of gills that are situated inside their bodies, and the cartilaginous fish have gill slits on the outer side of their bodies, present on both sides. In the cartilaginous fish, the teeth, nostrils on the side of the head and the tiny tooth like scale are not fused together to the jaw.