What animals live in the sea?

There are more species of animals living in the sea than on land.

The animals of the sea are: there are more than 200,000 species of marine animals, and they have a variety of forms, ranging from microscopic single-celled protozoa to higher mammals - cetaceans; Marine animals can be divided into three large groups: marine invertebrates, marine protochordates, and marine vertebrates.

1. Sharks. Sharks have been on Earth since 300 million years before the appearance of dinosaurs, and they have been around for more than 500 million years, and they have barely changed in nearly 100 million years. Sharks, known as sharks, sharks, and sand fish in ancient times, are behemoths in the ocean, so they are called "wolves in the sea".

The conventional wisdom is that sharks' cartilage (i.e., shark fins) is high in protein, but this is wrong.

Eggs have far more protein than shark fin. In addition, studies have shown that sharks are prone to mercury accumulation and shark fins contain a certain amount of neurotoxins, which are potentially harmful to humans. Sharks are at risk of extinction because of decades of mass hunting.

2. Whales. Whales are divided into two categories, one is baleen whales and the other is toothed whales. Whales belong to the phylum Chordates, subphylum vertebrates, mammals, and eumatria, which contain about 98 species of viviparous mammals living in oceans and rivers.

There are more than 30 species in China's waters. All but a few species of whales live in freshwater, and all but a few inhabit the ocean. The definition of the whale itself is vague, and the whale can encompass all cetaceans, as well as specific families of cetaceans. All dolphins are also included in the whales.

3. Octopus Octopus: It is the common name of 252 species of marine mollusks in 26 genera of the octopus family. It is the largest family of cephalopods, which can be divided into the subfamily of deep-sea myriapods, the subfamily of Aerdoudae, the subfamily of cephalopods and the subfamily of cephalopods.

The body is ovate or oval, muscular, the mantle cavity has a narrow opening, and the body surface is generally without water holes. Wrist suction cups 1 or 2 rows.

The third carpal stemmed on the left or right side of the male, with a seminal groove on the ventral margin of the wrist and a spoon-shaped lingual lobe at the end; The stemmed wrist cannot be self-broken. Funnel jacket lock degraded. 1 pair of vestigial needle-like inner shells or no inner shells. If there is a toothed tongue, the teeth on the side of the tooth tongue are usually single-cuspid. The stomach and cecum are located at the back of the digestive glands.

Fourth, jellyfish. Jellyfish: It is an important plankton in the aquatic environment and belongs to the class of spinophiles.

Jellyfish are a very beautiful aquatic animal. Its body is shaped like a transparent umbrella, and the diameter of the umbrella body can be large and small, and the diameter of the umbrella body of the large jellyfish can reach 2 meters. The edge of the umbrella has a number of whisker-like tentacles, some of which can be up to 20-30 meters long.

5. Sea turtles. Sea turtles belong to the order Turtles, Turtles, and Turtles. It is widely distributed in the Atlantic, Pacific and Indian oceans.

Chinese sea turtles are found in the coastal waters of the Beibu Gulf from Shandong in the north to the south of the Beibu Gulf. It can be more than 1 meter long and has a lifespan of about 150 years. There is a pair of forehead scales on the top of the head.

The limbs are like oars, the forelimbs are longer than the hind limbs, and each has a claw on the inside. The head, neck, and limbs cannot be retracted into the nail. Feeds mainly on seaweed.

Encyclopedia — Sharks.

Encyclopedia – Whales.

Encyclopedia — octopus.

Encyclopedia — Jellyfish.

Encyclopedia — Sea turtles.