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.
The longspine squirrelfish (Holocentrus rufus) is a silvery red, sea fish with orange-gold body stripes. One of about 150 species of squirrelfish, their most distinguishing characteristics are their large eyes and the long third spine of the anal fin. It is often included in public aquarium displays.The length of the longspine squirrelfish is about 18 cm (7.8 inches).It lives in coral reefs in tropical and warm temperate seas and eats zoobenthos.he body of the longspine squirrelfish is silvery red, with orange-gold body stripes. Its eyes are very large, which is characteristic of all squirrelfish. The rear dorsal fin is pronounced and sticks up. The anal fin has a strongly elongated third spine, from which this squirrelfish gets its name.