A different kind of sight & then some :)

Another mystery solved.  :)

Now that we've witnessed this behaviour for the first time, it's become clear that the narwhal tusk is a multipurpose appendage that really was worth the cost of evolving the most unusual tooth in nature.

Late last year, researchers discovered that this tusk helps narwhals 'see' like no other species on Earth - when they measured the whales' echolocation skills, they found that they have the most directional sonar ever detected.

Like dolphins and other whales, they're able to navigate dark, murky waters by producing clicking sounds at a rate of up to 1,000 clicks per second, and using the echoes to reconstruct their surroundings based on how the sound waves bounce off nearby prey or rock formations. 

Previous research had found that the narwhal tooth had foregone the protection of hard, external enamel to make it sensitive to even the tiniest of stimuli - and this appears to have given them the edge over all other echolocating species.

Nature never disappoints. :)