The famous "killer" in the marine world - sharks, sharks belong to the vertebrate phylum Cartilaginous plate gill subclass, marine life, a small number of species into the fresh water, its swimming speed is very fast, when catching prey is accurate and fierce, many other marine animals are difficult to look back.
The shark's most powerful weapon is its rows of white sensen's sharp teeth, which the shark uses to hunt. Sharks are indeed the strongest in the marine ecosystem... Sharks can be found in tropical and subtropical oceans, as well as in temperate and boreal waters.
Sharks are cartilaginous fish, and there are about 800 species worldwide. There are more than 190 species of sharks living in China's waters. Whale sharks can weigh up to 80 tons and can reach a body length of up to 25 meters.
In fact, sharks are not all that big, there is a shark called orange yellow shark, only 35 cm long. Compared to the whale shark, it is really a very small "little man" brother. The odd-looking sawshark has a peculiar predation method. It has a "long saw" evolved from the upper jaw, which is a sharp bone plate "saw", as long as the saw shark holds the "saw" and swings it left and right in the sea, many small fish will die in an instant.
The cat shark can actually catch birds flying in the sky, what are its strange predation tricks? It turns out that cat sharks will be half-floating on the surface of the sea when they "want" to eat birds, like a reef in the sea. The bird was tired of flying and was looking for a place to rest, so it landed on the cat shark. At this time, the cat shark slowly sank the back half of its body, and the bird slowly moved forward, just moving to the head of the cat shark, and the cat shark swallowed it in one bite.
Did you know that sharks have electronic organs? In the shark's nasal cavity, there is an organ shaped like a leather tube, this organ is called the "Roren's clip", which can form a weak electric field around the shark's nose to radiate electromagnetic waves like an antenna. It is by receiving "echoes" that sharks discover objects that are beyond their sight. Therefore, some small fish hidden in soft mud or sand are also doomed.
Sharks feed mainly on tiny plankton, but they also prefer to eat small fish, turtles, seabirds and small marine mammals. Sharks are gluttonous and taste everything, and they can swallow nylon coats, notebooks, rags, leather boots, ship number plates, leg of lamb, pig's head, steel helmets and other miscellaneous items, which is amazing.
Sharks are omnivorous fish. As for its cannibalism, it is only a few shark behaviors, such as the great blue shark, the hammerhead shark, the conetooth shark and the man-eating shark. Can you believe that sharks can also be witnesses and aides in solving cases?
In the autumn of 1935, fishermen near Sydney, Oceania, caught a giant tiger shark alive and sold it to a local aquarium for visitors to see and enjoy like a thunder reward.
On the eighth day of the exhibition, the shark suddenly spat out a complete human arm from its mouth, frightening the visitors who were watching. According to the forensic medical examination, the arm was cut off by a knife, not by a shark bite. Using this broken arm as a clue, the police uncovered a cabal that wanted to blow up the cruise ship and demand huge insurance money.
There is an anti-cancer substance in the shark's body. Of the 25,000 sharks, only 5 have mild tumors in their bodies, and only 1 of them is suspected of being malignant.
Scientists at the University of Miami in the United States have found that shark serum can kill bacteria and viruses, as well as human cancer cells grown in vitro. Scientists expect that in the near future, sharks will help humans defeat cancer viruses.