Drone video has filmed something no one has ever seen before: wild narwhals using their strange tusks to target Arctic cod by striking them and stunning them, making them easier to eat. The behavior sheds light on a long-standing biological puzzle: why have these rare and enigmatic whales developed an extra-long left canine tooth that emerges through the upper lip and protrudes from the head like a unicorn’s horn?
Since narwhals spend the majority of their lives concealed beneath the Arctic ice, little has been known about the tusk’s role. Researchers believe the tusk, which grows in a spiral pattern out of the animal’s head, was used as an atmosphere sensor or to catch fish.
Early Theories and Brief History of the Narwhal
To start with, not all narwhals possess tusks, and a few do, including one on exhibit at the Smithsonian’s Sant Ocean Hall. To begin with, the tusk of a narwhal is simply an overgrown spiralized tooth, and it is one of only two teeth they will ever have. In reality, if you happen to see a narwhal in the wild, you may not consider it as one at all, because many of them lose their tusks over time (hence its enigmatic and obscure reputation!).
From base to tip, the tusk is thought to have 10 million tubules, which are fluid-filled channels. They provide a direct link between the narwhal nervous system and the rest of the world. Tubules abruptly stop in the layer well before the outermost enamel coating in the teeth of other species.
In 1915, the world’s biggest entrapment destroyed over 1,000 narwhals at once. Narwhals will profit immensely from understanding when ice changes would occur because they live in such a dangerous climate. The tusk comes into play at this stage. According to one study, the tusk’s sensory capabilities could be high enough to detect changes in ocean salinity. The saltiness of the ocean is linked to the presence of sea ice—like ocean water freezes, salt is left behind in the surrounding water.
According to another new study, the true evolutionary function of these horns, which can grow to be 8 feet long, is related to sex: The tusks, like a peacock’s ostentatious feathers or an elk’s intricate antlers, are used by male narwhals to bid for and attract mates, according to the study.
The Drone Footage You Have Been Waiting For
Two drones flown by Adam Ravetch of the World Wildlife Fund (WWF) Canada and scientists from Fisheries and Oceans Canada captured the footage in Tremblay Sound, Nunavat, in northeastern Canada.
Brandon Laforest, a senior specialist of Arctic species and ecosystems with WWF-Canada, told National Geographic, “This is an entirely new observation of how the tusk is used.” Scientists have suggested a variety of potential roles for these ‘horns,’ which can grow up to 2.7 meters (9 feet) long, including testicle size indicators, navigation, and territorial conflicts.
They traverse dark, muddy waters by making up to 1,000 clicks per second of clicking sounds and using the echoes to recreate their surroundings based on how sound waves rebound off distant prey or rock formations, much like dolphins and other whales.
Previous studies had discovered that the narwhal tooth had lost its strong, exterior enamel, rendering it highly sensitive to even the slightest stimuli, giving them an advantage over all other echolocating animals. The tooth is thought to play a role in echolocation by allowing seawater to penetrate through pores in its top, according to scientists. Bubbles then move up the shaft and excite nerve endings near the narwhal’s ears, transmitting information to the brain about the narwhal’s surroundings.
It’s worth noting that the behavior captured by the drone has yet to be published in a peer-reviewed journal, so any interpretations of what we’re seeing would need to be independently checked.