Meet the ‘Unicorn Puppy’ With an Extra Tail on His Head

Narwhal’s unique appendage may be the remnant of his parasitic twin

Sweet Narwhal will be adoptable soon, but he is not for sale. He is a very good boy, of course. Courtesy of Mac’s Mission

As the owner of a Missouri shelter for dogs with special needs, Rochelle Steffen has encountered her share of pooches who require unique care. Some have had birth defects—like spina bifida, and even an extra leg, she tells Today’s Scott Stump—and others have been injured or abused. But Steffen had never seen a dog quite like the puppy who came to her shelter, Mac’s Mission, last week.

Right between the pup’s sweet dark eyes is an extra appendage that looks very much like a second tail. Steffen named the little one Narwhal, after the whale that sports a protruding, tusk-like tooth, but the media has dubbed him the “unicorn puppy.” And he has quickly become a bonafide viral sensation.

Writing on its Facebook page, Mac’s Mission says that as news of Narwhal has spread, the group has received more than 300 applications for his adoption. One person offered to buy him for $7000. But Narwhal “is not for sale," the group notes. "He will be adoptable at some point and we truly have zero idea how we are navigating the process yet.”

Mac’s Mission took Narwhal in after he was found wandering the Kansas City area. He’s around 10 weeks old, and might be a Dachshund-terrier mix, perhaps with some golden retriever genes too, Steffen tells Stump.

The puppy had frostbite on two of his toes, and needed to take medication for worms, reports Hannah Knowles of the Washington Post. Brian Heuring, a veterinarian at Cape Small Animal Clinic in Cape Girardeau, Missouri, took X-rays of Narwhal and found that his tail is “all just skin,” Heuring explains in an interview with Stump. The appendage lacks the vertebrae that dogs typically have in their tails, and so, to Steffen’s slight disappointment, Narwhal’s extra tail does not wag.

But the puppy seems to be in good health, and his head-tail isn’t giving him any medical trouble. In fact, Narwhal been very busy attending to typical puppy business—namely playing.

“I certainly do not see anything that's causing any harm or complications,” Heuring says. “The puppy couldn't be any sweeter or happier.”

Mac’s Mission does not intend to have the tail removed. The group writes on Facebook: “[Y]es he is keeping it.”

It’s not entirely clear what caused Narwhal’s unique birth defect, but Elizabeth Preston of the New York Times reports that it may be a remnant of his parasitic twin. Dogs, like humans, can conceive identical twins, which happens when an embryo splits after fertilization. Sometimes, one of the twins will stop developing during gestation but remain attached to its normally-developing sibling, manifesting as extra appendages or organs.

Cases of parasitic twins have been documented in humans, but to see the phenomenon in dogs is “really super, super rare” because dogs only rarely conceive identical twins, Margret Casal, a professor at the University of Pennsylvania School of Veterinary Medicine, tells Preston. Still, Casal thinks little Narwhal may be sporting the vestiges of his sibling; the crest of hair above the pup’s extra tail may “suggest a twin’s rear end on Narwhal’s face,” Preston writes.

To Narwhal’s new legion of fans, these quirks just make him all the more loveable. (Some have promised that they “would die for Narwhal.”) The Mac’s Mission team hopes that their celebrity puppy will help bring attention to other dogs with unique needs.

“My story being viral helps ALL our special needs dogs here at the Mission,” reads a Facebook post written in Narwhal’s voice. “I am super excited for being the poster child for ‘special is awesome.’”

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