The Inuit they know them well and have studied them since the dawn of time: i narwhals (Monodon monoceros), also called “sea unicorns”are cetaceans, i.e. marine mammals, typical of the Arctic and unique in their kind due to the presence of the characteristic “horn”. This protuberance with alleged magical properties is nothing more than ahuge tusk which develops in males of the species (in very rare cases also in females). There are several theories about the functionality of the “horn”: for a long time it was thought that it was just a secondary sexual character (like peacock feathers), but it has been seen that it is a means of communication between different specimens, a tool for stun the prey and even a profit radar sensory to perceive variations in temperatures, vibrations and salinity of the water, allowing the narwhals to orient themselves among the ice.
Is the narwhal’s horn really a horn? No, it’s a tooth
What is commonly called “horn” it’s actually a toothto be precise the upper left canine. When young males approach 2-3 years of age, this bizarre structure grows and lengthens, pierces the jaw and comes out, spiraling into counterclockwise.
In reality, two teeth initially develop only one grows following this scheme. In addition to these, narwhals also have vestigial teeth, which are very small and less conspicuous. As a rule, females do not develop horns, although it is not yet clear why: in fact, cases of female specimens equipped with this mammoth tooth are rare.
This huge pointed spear it is flexible and innervatedcan grow up to 10 foot and is capable of bend over up to 30 cm in all directions. The growth of the tusk leads to the deformation of the skull which is thus asymmetrical.
What is the narwhal tusk for: a tool for communication and orientation
The fact that only the males possess the fang, has long suggested that it was a secondary sexual character linked to sociality and mating, a bit like what happens in peacocks with bright tails or lions with manes. Simply put, the more conspicuous and robust these traits are, the more they increase social status. To give a slightly more concrete example, their function seems similar to that of the deer’s antlers, charismatic for the female counterpart but still weapons for winning duels against other adult males.
But let’s not forget that they also have a role in communication between similar, as for example in tuskinga typical behavior that consists of crossing the fangs out of the water as if they were swords. In addition to these just described, thanks to new data coming from chemical, physical, biological and genetic studies combined with Inuit knowledge, new imaging techniques and remote sensing, researchers have managed to hypothesize various theories for explain the presence of a character so extraordinary and cumbersome.
A first theory involves the use of the tusk for capture of prey. If you believe that fish are skewered like pieces of meat on a skewer, you are wrong: this very dramatic hypothesis has been proven wrong. Instead, we have evidence of how narwhals can use the enormous tooth to hit prey and stun them.
Another hypothesis, which does not seem to exclude the first, considers the tusk a very strong sensory organgiven the presence of a dense network of over 10 million nerves. Following this trail the “horn” would be extremely useful in the perception of vibrationsfrom the temperature and of salinity of the water surrounding environment and, consequently, to know how to move in the thick blanket of Arctic ice. This makes it possible to understand the topology of ice and ice places to take a breather. On the other hand, they know how to stay underwater for a long time but they still need to breathe.
What animal is the narwhal?
The narwhal it is undoubtedly a curious creature that does not go unnoticed. With that “thing” of his that comes out of his head he earned the nickname “unicorn of the sea” which, in the scientific world, is adapted into Monodon monoceros from the Greek, literally, “a tooth, a horn”. Its common name, however, is supposed to derive from the ancient Norse term nafarr what does it mean “auger“.
Although shy, narwhals have always aroused a lot of curiosity and have been extensively studied, leading us to have a fairly solid understanding of their ecology, biology and behavior. From a taxonomic point of view they are toothed cetaceansmarine mammals which include dolphins, sperm whales and killer whales. They live and move in social groups in the area of Arctic Circlealong the coasts of Canada, Greenland, Alaska, Iceland and Scandinavia, swimming between the Barents Sea and in theArctic Ocean.
They derive from a group of terrestrial ungulates that returned to the sea, from which they inherited and maintained a digestive system made up of multiple chambers (like that of terrestrial herbivores), then adapted to a carnivorous fish-based diet. These marine mammals can reach just under two tons in weight For 5 meters longunless we consider their most obvious feature: their enormous size tusk that they carry with them.
Curiosities about sea unicorns
Although usually only one horn develops and only in males, a singular find can be seen at the National History Museum in London: a specimen that presents two “horns”dating back to a voyage in arctic waters dated 1949. Even more spectacular is the skull preserved in the Zoological Museum of Hamburg, dating back to 1684: two enormous teeth in a specimen which is thought to be female, according to the stories of the seventeenth century, but DNA analyzes are underway to confirm it or not.
If you think that the rarity goes hand in hand with profit, you are right: in the past the narwhal horn has managed to be worth up to 500 times its weight in gold. But who bought it and what to do with it? Nobles, bourgeois and wealthy personalities gained from it jewelrymagic potions, poisons And toning come on alleged aphrodisiac properties. But the situation has not changed much: the ivory from which the tooth is made, like that of elephants, is still very popular and requested on the black market. The poaching of these protected species is still quite active and represents a real danger for the survival of the species.
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