How narwhals keep their 10-feet tusks remarkably straight

An international team of biologists, chemists and physicists has used sophisticated 3D X-ray technology to investigate the tooth at an unprecedented level. A unicorn may be a mythical creature, but nature made something very similar under the Arctic ice. Wondering what? Well, the narwhal has a strange tusk that can reach nearly 10 feet long from the animal’s head, erupting from its upper lip in a bizarre display that has intrigued people for centuries. Now, scientists have worked out a molecular explanation for one of its oddest features: how a tusk that twists as it grows can remain surprisingly straight. According to a study published by Phys Org, narwhals have one prominent tusk, usually found in males. The fact is that it is a canine tooth that grows through the jaw and upper lip and the corresponding right canine usually remains embedded inside the head. The tusk may grow to a length of some three meters (10 feet). Its unusual appearance helped fuel legends of unicorns during the Middle Ages, and narwhal tusks were sometimes sold as magical unicorn horns. But for today's scientists, the tusk is a very real challenge in research. Narwhals live much of their lives in the Arctic,...