Narwhals are Magic.

Now with proof!  Secrets of the narwhal’s tusk have recently been revealed in research headed by Martin Nweeia, a practicing dentist and clinical instructor at the Harvard School of Dental Medicine, who just happens to also be a member of the Vertebrate Zoology Department of the Smithsonian’s National Museum of Natural History. With a team of researchers/coauthors, including Jim Mead, Vertebrate Zoology Curator Emeritus and Charlie Potter, Marine Mammals Collection Manager, Nweeia just published a paper in the journal The Anatomical Record about the discovery of neural pathways that run from the narwhal’s tusk to its brain. The arctic whale’s unicorn-like tusk acts as a sensor, specifically detecting variations in water salinity. Read more on the Smithsonian Science blog, or see the original article at Anatomical Record (You might want to head to your local library to see if they have access since it’s behind a paywall).
There are some pretty great images of narwhal’s over on the Biodiversity Heritage Library’s Flickr page, too.

Paul Stuart - ‘Man-on-the-fence’ logo originally created by J.C. Leyendecker in 1921

Landing Fish, St. Ives, England 
Richard Haley Lever

Leonid Brahilovsky - The Blue Moscow, 1920th

Cherry Blossoms in the Moonlight - Kaii Higashiyama

Ramendranath Chakravorty (1902-1955)

Frog Cabinet - Madeline von Foerster

Portrait of a Lady in a Pink Dress, seated (Detail)
Jan van Beers (1852-1927)
Oil on panel