Narwhal's Trademark Tusk Acts Like a Sensor, Scientist Says
The Arctic whale's tusk is actually a tooth that can grow more than nine feet long; it has baffled people for centuries.
On Tuesday, scientists published a study that advances a bold theory about how the whale uses its tusk. They say the horn, which is actually a tooth, is a sensory organ.
The scientists speculate that the tusk, usually found only the males, can pick up differences in the whale's environment, like the salt content of seawater, helping the marine mammals to navigate their frigid homes or perhaps find food.
But the theory is highly controversial; many marine mammal experts reject the idea that the tusk plays a central role in a narwal's ability to sense its environment, insisting that the tooth is most likely a lure to attract mates. (Related: The Mystery of the Sea Unicorn)
"There's just zero evidence" for the