Dolphins, like whales, are descendants of terrestrial mammals, and all probably belong to the phylum Artiodactyl. The ancestors of today’s modern dolphins may have entered the water about 50 million years ago during the Eocene.

Modern dolphin bones have two small, rod-shaped pelvises and are given atrophied hind legs. October 2006, a strange bottlenose dolphin was caught in Japan; This fish has 2 small fins on either side of the genital slit and is determined by scientists to have developed hind legs.

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Dolphins are marine mammals that are closely related to whales. There are nearly 40 species of dolphins in 17 genera that live in the oceans, with a few remaining in some rivers around the world. The size of the dolphin can range from 1.2 m and 40 kg, up to 9.5 m and 10 tons

There are nearly 40 species of dolphins in 17 genera that live in the oceans, with a few remaining in some rivers around the world. Here are a few types of dolphins most famous and familiar to man.

Ocean Dolphin (Sea Dolphin):

Bottlenose dolphin

Killer dolphin

White dolphin

Freshwater Dolphins (River Dolphins):

Amazon River Dolphin – Pink Dolphin

Red-tailed Blue Dolphin – Western Dolphin

Dolphins – Dolphins

Dolphin is a fish with a large body size and the dolphin body is diamond-shaped and smooth down to the tail. The compact body allows the dolphin to swim at high speed.

The smallest dolphin species is 1.2m, the longest is 9.5m. Their weight also ranges from 40kg to 10 tons. This species evolved from terrestrial mammals. Dolphins have a torpedo-shaped body, their neck is usually not flexible.

The limbs of ancient animals evolved into flippers to adapt to the aquatic environment.

Dolphins do not have external ears, the head and skull of the dolphin are quite small, the eyes of the fish are small.

The eyes are placed close to the corner of the mouth, the fish’s snout is quite long and pointed.

The part of the dolphin’s teeth resembles a cone, which makes it easier for the fish to hunt and crush the prey.

Dolphins and things to know

Dolphins are a line of fish that evolved from terrestrial mammals, so they breathe through lungs. They breathe by inhaling air into the blowhole at the top of their head, and when they exhale, they spray a hose upwards towards the surface of the water.