The function of the curious unicorn-like tusk of the narwhal (Monodon monoceros) has long been a puzzle to researchers. However, a researcher from the Harvard School of Dental Medicine is to present a paper about the tooth’s function at the 16th Biennial Conference on the Biology of Marine Mammals, writes the Harvard Gazette. Martin Nweeia has studied the animals over 4 trips to the Canadian high Arctic and has concluded that the tusk is a “hydrodynamic sensor”. Ten million nerves connections are in its outer surface which, he believes, gives information about water temperature, pressure, and particle gradients. The ability to detect particle gradients may allow the animals to discern the salinity of the water around it, directing it to ice-free ares. It may also allows the whales to “sniff” out water particles characteristic of the fish that constitute their diet.