Why are seahorses called seahorses?
Dolphins are mammals, not fish. The Eastern Spinner Dolphin is distinguished by its triangular dorsal fin and uniform gray color. Even though they live in the ocean all of the time, dolphins are mammals, not fish.
Dolphins are mammals, not fish. Also, like all mammals, dolphins even have a tiny amount of hair, right around the blowhole, which is a little different than the scales of a fish. Whales and porpoises are also mammals. There are 75 species of dolphins, whales, and porpoises living in the ocean.
Like every mammal, dolphins are warm blooded. Unlike fish, who breathe through gills, dolphins breathe air using lungs. Dolphins must make frequent trips to the surface of the water to catch a breath. The blowhole on top of a dolphin’s head acts as a “nose,” making it easy for the dolphin to surface for air.
Dolphins cannot breathe in water using gills as fish can, do not have scales, and are not cold-blooded. Dolphins are mammals that returned to the sea millions of years ago. Being a mammal means that: they breathe air (and do not have gills like fish);
Jellyfish are not really fish, of course, because a fish’s anatomy is centered around its backbone, whereas the jellyfish is a dome-shaped invertebrate. The cnidocytes on jellies’ tentacles discharge venom from a sac called a nematocyst. These help them to capture floating prey in the water column.
Like every mammal, dolphins are warm blooded. Unlike fish, who breathe through gills, dolphins breathe air using lungs. Other characteristics of dolphins that make them mammals rather than fish are that they give birth to live young rather than laying eggs and they feed their young with milk.
Seahorses are tiny fishes that are named for the shape of their head, which looks like the head of a tiny horse. There are at least 25 species of seahorses. You’ll find seahorses in the world’s tropical and temperate coastal waters, swimming upright among seaweed and other plants.