China Aquatic Products Channel reported that in the current Western mythology, the legend is shaped like a white horse, with a spiral horn in front of the forehead, representing a noble, proud and pure beast called a unicorn, in fact, the prototype should be an Indian rhinoceros, typically with a long horn on its head. And today I want to introduce you to a beast with a long horn on its head, of course, people are not beasts, but whales, narwhals.
Narwhals, also known as horned whales and gibber whales, are always associated with legendary unicorns in the general public's impression, because male narwhals have long, spiral-shaped horns, making them closer to the image of the legendary unicorn than any creature in the world.
Narwhals inhabit the Arctic region mainly , with a small , rounded head and no protruding beak. The forehead bulges out and is slightly upturned in front of the mouth. The pectoral fins are small and broad, but short in length, with slight upward curvatures at the ends. The posterior edge of the tail fin of an adult whale is protruding like a convex mirror, and when viewed downwards, it resembles the wings of a butterfly. It does not have a dorsal fin , but has a low fleshy bulge in the posterior half of the back.
The most iconic part of the narwhal is certainly the horn on its head, but it is not a real horn, and unlike the horn of a cow and a sheep with horns on its head, the horn of the narwhal is actually his tooth. Studies have found that in fact, all narwhals lack functional teeth in their mouths, especially females, most females have no teeth for life, and the male whale has two teeth in the upper jaw on the left, note that only the left tooth will protrude outside the lip at two to three years old and continue to grow, the protruding part can reach 2.7 meters long and weigh more than ten kilograms, according to the study, narwhals in the embryonic period, originally had 16 teeth, but they were not developed, by birth, most of the teeth were degenerated and disappeared, only the two of the upper jaws were retained. The female whale's teeth are always hidden in the upper jaw, and it is considered that the female narwhal is toothless for life.
The tusks on the head of male narwhals, on the other hand, are mostly left-helix, mostly hollow inside, and the axis remains straight, but sometimes twisted. But it has also been found that there are also a very small number of male whales that will even have the right tooth protruding from the lip, forming a rare case of "double tusks", but the extra right teeth are usually shorter than the left one.
Most mammals have a layer of wear-resistant enamel on the surface of their teeth, but this unicorn does not. The bone of the tooth is directly exposed to the outside, the inner layer is ivory, and the center is a hollow pulp. Moreover, the study also found that in addition to the small holes in the bone of the tooth, the single tooth extended inwards and could even find dense passages on the ivory. These channels are finally connected to the nerve cells on the pulp, and then they are merged into the horn base, and finally these messages are transmitted to the brain, so the single horn should be used as a "sensing organ" to receive environmental changes such as salinity, temperature and pressure.
Narwhals feed mainly at the depths of the ocean, feeding on pelagic fish cod, squid, shrimp, and benthic organisms such as the Greenland halibut. Dives can take up to 20 minutes and are more than 1,000 meters deep. You may think that narwhals use the tusks on their heads to poke their prey, but in fact, it is not, the way of hunting is relatively simple and rough, there are no functional teeth, so it is swallowed in one bite, and the whole prey is swallowed in one bite.
Narwhals also have migratory habits, and scientists believe that the migration of narwhals seems to be related to the formation and movement of sea ice, and when the ice layer is incomplete or ruptured in the spring, the narwhals move with the shrinking boundaries of the ice floes and quickly cross the fjords between small cracks and melting pores. When the winter ice expands again, they look for waters where the ice continues to move for the winter.
The "horn" of the narwhal is very precious, the price of whale teeth is expensive, it is rare to find, and it has also become the source of the narwhal disaster. Many people hunt narwhals to obtain fangs, so much so that the countries concerned have to take measures to protect them. In fact, the real practical value of the narwhal is not the teeth, but the skin and flesh under the skin of the body, there are 5 cm - 10 cm thick fat can be extracted from a large amount of whale oil, the local Eskimos feed on it or use it for heating; and its skin is rich in vitamin C, which is the main source of vitamin C supplementation for the local human body.
Although prohibited, narwhal populations are declining very rapidly, mainly due to unnatural deaths from overhunting, as well as warming climates and food shortages from commercial fishing in the Arctic. Although narwhals can live for up to fifty years, they reproduce slowly, are genetically homogeneous, have only one birth every three years, take 15 months to become pregnant, and lactate for up to 20 months, and only after weaning can the young whales live independently. In addition, scientists believe that thousands of years ago, a large number of narwhals were trapped by ice and died en masse, which is the reason why today's genetic composition is too single.
Narwhals live in icy Arctic waters and huge water pressures, so why deliberately expose their dental tubes? From an evolutionary point of view, it should also be for survival.
Every narwhal has long teeth on its head, so when they get together, will they accidentally poke other friends?
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