List the signs of fish.

Fish have their own characteristics. We can easily identify fish from other inhabitants of the aquatic environment. First of all, this is that fish have a special body structure, which is streamlined. Also, the body of the fish is covered with scales. Fish have fins. It is a pair of pelvic and a pair of anal fins, a caudal fin and two dorsal fins. Fish are heterotrophs by the type of feeding. Three parts of the body can be distinguished – head, torso and tail, which smoothly merge into one another. These are the main features of fish.