What are the creatures on the bottom of the sea? What are the creatures in the sea

Underwater animals include: sharks, whales.

Dolphins, jellyfish, manatees, etc., their characteristics are as follows:

1. Sharks. Sharks have hard, muscular bodies that are spindle-shaped to varying degrees. The muzzle and nose parts vary depending on the species, from pointed to large and rounded. The tail (caudal fin) that rises vertically upwards is roughly crescent-shaped, and the upper part of the caudal fin is much larger than the lower part in most species.

2. Whales. Whales are large, some with large bodies, and the largest can reach a length of up to 30 meters. The whale is shaped like a fish and is in the shape of a shuttle.

The head is large, the eyes are small, and the ear shells are completely degenerated. The neck is not noticeable. The forelimbs are fin-shaped, and the hindlimbs are completely vestigial; Most species have fins on their dorsal backs; The tail is horizontally finned and is the main locomotor organ.

3. Dolphins. The dolphin is meters long and weighs 23,225 kilograms. Dolphins generally have a pointed mouth and upper and lower jaws.

Each has about 100 thin teeth, mainly small fish and squid.

Shrimp and crabs are fed.

4. Jellyfish. Jellyfish do not have a spine, but they have a very large body, relying mainly on the buoyancy of the water to support their huge body. The body shape is 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.

5. Manatee. Due to their adaptation to life in the water, manatees specialize in cones on their forelimbs, but they still have vestigial hooves at the ends, which are closer to ungulates. The hind limbs gradually degenerate and disappear, and the tail is a round broadwhale.

There are countless creatures in the sea, and the list is endless. Sharks, whales, dolphins, octopuses, abalone, tuna, conch, turtles, seals, sea lions, walruses, jellyfish.

Including marine animals, marine plants, microorganisms and viruses, among which marine animals include invertebrates and vertebrates. Invertebrates include a variety of snails and shellfish. Vertebrates include a variety of fish and large marine animals.

Marine animals: sharks, whales, jellyfish, etc.

Marine plants: kelp, wakame, staghorn, kelp, hijiki (sargassum), etc.

Marine microorganisms: The marine environment is characterized by high salinity, high pressure, low temperatures, and thin nutrients compared to land. Marine microorganisms have their own unique characteristics because they have adapted to the complex marine environment for a long time and survived.

Why do so many creatures live in the sea? What secrets are hidden in the depths of the sea?

1. Blue whaleIt is a marine mammal of the baleen whale family and the genus Baleen Whales. There are 4 subspecies. The blue whale is believed to be the largest animal known to have ever survived on Earth, reaching up to 33 meters long and weighing up to 181 tons.

The blue whale has a slender body and a blue-gray back, although it can sometimes be lighter in the water.

2. Killer whalesIt is the largest species in the mammalian and dolphin families. It is found in almost all ocean areas, from the equator to the polar waters. There is no limit to its range by water temperature or depth.

The distribution extends to many closed or semi-enclosed seas, such as the Mediterranean, the Sea of Okhotsk, the Gulf of California, the Gulf of Mexico, the Red Sea, and the Persian Gulf.

3. Weasel shark, often near estuaries and harbor activities; Nocturnal, feeding at night to shallow water and daytime to deep water. Ferocious and greedy, it preys on bony fish, other sharks, stingrays, marine mammals, turtles, seabirds, etc. It is widely distributed in the world's oceans between north and south latitudes of 40°.

In China, it is distributed in the Yellow Sea, the East China Sea, the northeast and southwest seas of Taiwan, and the South China Sea.

4. Hexigill sharkIt is a species of shark of the phylum Vertebrates, Subphylum Vertebrates, Cartilaginous Fishes, Subclass Plategils, Hexagill Sharks, Hexagillidae, and Hexagills. It was found at a depth of 1,400 meters in the Coral Sea of Australia.

5. Atlantic bluefin tunaIt is an oceanic pelagic migratory fish. It can withstand a considerable range of temperatures, living both above and below the thermocline at depths of more than 9,850 meters. Tie the knot and swim fast.

When juvenile, Atlantic bluefin tuna exhibit a strong social swimming habit.

The above content reference: Encyclopedia - Atlantic bluefin tuna.

The above content reference: Encyclopedia - Hexagill Shark.

The above content reference: Encyclopedia - Weasel Shark.

The above content reference: Encyclopedia - Killer Whales.

The above content reference: Encyclopedia - Blue Whale.

Corals, various marine plants (seaweed, kelp, etc.), marine plankton, molluscs (starfish, jellyfish, sea cucumbers), various shellfish, fish, mammals (dolphins, whales) and many more.

The animals in the sea include seahorses, sharks, jellyfish, tuna, crabs, squid, octopus, turtles, oysters, whales, abalone, hairtail, white minnows, minnows, redfin fish, tenchfish, dolphins, sea lions, etc.; There are mainly algae plants in the sea, such as cyanobacteria, red algae, brown algae, green algae, coral, kelp, sponge, spirulina, rotaphylla, etc.

Most of the animals that live in the sea are aquatic animals that have not been separated from the water during the evolution of the species, or aquatic animals that have been transformed from terrestrial animals to aquatic animals, and they can carry out aerobic respiration in the water, such as whales, which use their lungs to breathe.

The plants in the sea are mainly algae, and sometimes there are others, such as algae plants multiply very quickly, so in some sea areas, the wild growth of algae will cause eutrophication of seawater, affecting the life of animals in the sea, and also affecting the growth of nearby plants.

These animals and plants are interdependent, for example, after the death of animals, the corpses decompose to become the nutrients of aquatic plants, and many plants are the food of animals, so they are indispensable to others.