Giant sensor

The narwhal's most prominent feature is its long spiral tusk. And people have long been curious to know what the tusk is for. Some thought that narwhals were proof for the existence of unicorns and that the tusk had magical powers. Others variously said that the tusk was used for ice breaking, catching fish (using the tusk like a spear), and self-defence. But now Dr. Martin Nweeia, from the Harvard School of Dental Medicine, has thrown up a new possibility. According to him, the tusk contains many million nerves that help the sea mammal detect changes in the water pressure and temperature. The tusk, which could be between six and nine feet long, thus acts as a giant sensor helping the animal test the water and find its food. Narwhals are rarely seen but they live in the Arctic Ocean and can grow up to 15 feet in length. This discovery now opens up more possibilities for scientists on the uses of the narwhal's tusk.

Wish You all a Happy Pongal (boiling is the English name for Pongal)