Before we officially begin this article, let me ask: Whale shark, is it a whale or a shark?
Whale sharks, scientific name Rhincodon typus, English whale shark, belong to the cartilaginous fish order Baleenidae whale shark family, is currently the world's largest surviving fish. They are relatively "late-maturing", reaching sexual maturity around the age of 30 and can live up to 70-100 years.
How big are whale sharks? Generally speaking, its body length is about 10 meters, the largest individual body length can reach 20 meters, and the weight is 10-15 tons.
The whale shark is named "whale shark" because of its large size as some cetaceans and its similar filter feeding habits to baleen whales. However , the bones in the whale shark are cartilage , and it is determined that it is the shark, not the whale.
The whale shark is large, gray-brown to blue-brown on the outside, and has many white spots and stripes on the sides of its body, which look like a little star in the night.
It also has an oversized mouth, which can reach a width of 1.5 meters, and 300 rows of tiny teeth on 20 filters. It also has 5 pairs of huge gills, and two small eyes are distributed in front of the head.
If you know a little about sharks, you will know that sharks have skin teeth on them, showing small V-shaped scales, and have a structure of fine teeth, which can reduce the resistance of water flow and help sharks swim faster.
However, it is more special that because the eyeball usually faces physical, chemical and biological hazards, the whale shark also has a "skin tooth" around the eye to protect its eye from damage. These skin teeth are called "eye teeth".
Figure | WWF WWF
In the journal Science Public Library General, researchers said in the paper published that whale sharks have skin teeth covering their eyeballs, which is a relatively different eye protection mechanism in cervical vertebrates, and the skin teeth on the eyeballs are not the same as the skin teeth distributed in other parts of the body, and the skin teeth on the eyes are to protect the whale shark's eyeballs, not to swim faster.
Whale sharks live in the middle and upper layers of the warm ocean sea all year round, which may also create the warm and gentle character of whale sharks. It swims slowly and often floats slowly on the surface of the sea to enjoy "sunbathing".
In general, whale sharks prefer to move alone, unless they encounter a food-dense area, at this time many whale sharks swim over at the same time to "eat", otherwise they will rarely gather together.
Although whale sharks can migrate long distances, according to studies, female whale sharks like to stay in the same area for a long time and return to the same location year after year. This is probably the whale shark's special "home" attribute.
Although the whale shark is large and looks like a hill, it is a docile filter-eater. The so-called filter-eating animals are animals that feed on plankton in water in a filtered manner.
What appears to be a rich recipe for whale sharks actually feed on tiny plankton, crustaceans, mollusks and small fish that follow the water into the whale shark's large mouth, filtered through the fine grid on the shark's gills, and thus remain in the whale shark's mouth.
Probably in the sea world, whale sharks are notoriously good-tempered, so you can often see a lot of small individual fish, such as bass, mackerel and juvenile fish of golden trevally, etc., in the whale shark around the phenomenon of "free riding".
In addition, whale sharks are not harmful to humans, and are often used as examples – "not all sharks are 'cannibals'" and can even play with divers.
However, the good-tempered whale shark is not in a good position at present, it is listed by the IUCN Red List: Vulnerable (VU), and it is also listed in the second level of the 2021 edition of China's National List of Wildlife under National Key Protection.
Because whale sharks are slow and like to sunbathe, humans can easily catch them. I hope that each of us can take action to protect endangered animals, so that in the future we can continue to see this cute, gentle big fish in the sea.