Narwhals are one of the most interesting and weirdest animals on the planet. These shy whales boast a long horn (that is actually a tooth) and live in the cold waters of the Arctic. Generally speaking, it is only the males that grow this long tooth, though occasionally a female will as well. Even rarer is that some males can grow two of the teeth, making them have double tusks.

There is one example of this type of specimen that is housed at the London Natural History Museum. The principal curator for mammals, Richard Sabin, is responsible for this part of the museum, and he is quite an expert on narwhals. He recently spoke with IFLScience about this ‘unicorn of the ocean’ and the rare specimen he has at the museum. He said:

“Double tusked narwhals are extremely uncommon. Both male and female narwhals possess two maxillary canine teeth inside their skull and whilst females do very occasionally grow a tusk, it’s most common for these to emerge in males on the left-hand side as a long, single spiralling tusk.”

Some of the tusks can grow as much as 3 meters (9.8 feet) off of the head, making them a very impressive sight. For a long time, experts didn’t know what they used their tusks for, but recent analysis finds that they are used for a variety of different things depending on the situation. Sabin talked about them, saying:

“The outer layer of a narwhal tusk does contain a huge quantity of nerve endings that some researchers have suggested gives narwhals a sensory ability to detect changes in the surrounding water (things like changes to temperature and pressure).”

There is even video footage of them using their tusks in a variety of ways, which can be seen here:

The researchers who captured the video saw them using their tusks to hit and stun different types of fish. They also defended access to their food from seabirds by poking them away with the tusk.

Another thing to add to the long list of things that make a narwhal weird is the fact that there is very little genetic diversity among the population. Normally, this would cause problems and make it difficult to sustain a population, but that doesn’t seem to be the case with these animals.

When asked what he found the most interesting about these mammals, Sabin answered:

“What do I find most fascinating about narwhals? The same thing I find fascinating about all cetaceans – that they returned to the ocean from the land and developed a hugely diverse range of anatomical, social and behavioural adaptations, that allow them to exist in an aquatic environment. Cetaceans are a key part of ocean ecosystems.”

If you ever want to see a live Narwhal, you’ll have to go out to meet them in the wild.

There have been very few attempts to keep narwhals in captivity, and they all ended in disaster, with the beautiful animals dying young. There is not likely to be any more attempts in the near future.

Thought that was fascinating? Here’s another story you might like: Why You’ll Never See A Great White Shark In An Aquarium