The sinister theory behind the rare 'unicorn' puppy

A 10-week-old puppy who became famous last week for his unusual facial feature may have absorbed his twin, experts say.

Narwhal, an abandoned golden retriever nicknamed the ‘unicorn puppy’, captured hearts across the world when images of the extra tail between his eyes became headline news.

But, the cause behind the unique appearance may be more sinister than initially believed, Margret Casal, a professor at the University of Pennsylvania School of Veterinary Medicine, told The Independent

Narwhal, an abandoned golden retriever nicknamed the ‘unicorn puppy’, captured hearts across the world when images of the extra tail between his eyes became headline news. Source: Mac the Pitbull

A pattern of backward-growing hair resembling a “mohawk” sits above the tail, indicating that Narwhal’s twin’s behind is on his face, she told the publication. 

The tail also has no bones, which Casal said helps prove her theory since the bottom of a spine cannot develop without signals from the top.

She said identical twins in dog litters are very rare - making the occurrence of a parasitic twin “really super, super rare.”

Parasidic twins occur when an embryo carrying splits asymmetrically late into the pregnancy. The remnants of one of the twins are then absorbed by the dominant twin - often leading to additional body parts.

Rochelle Steffen, owner of Mac’s Mission, a Missouri-based non-profit group, came across Narwhal earlier in November.

A pattern of backward-growing hair resembling a “mohawk” sits above the tail, indicating that Narwhal’s twin’s behind is on his face. Source: Mac the Pitbull

“We are thankful this baby and his buddy are safe from the freezing cold,” Mac the Pitbull wrote on Facebook.

A vet determined the tail is not harmful to the puppy.

“The extra tail is not connected to anything and has no real use other than making him the COOLEST PUPPY EVER!” Mac reported.

“Dr Heuring [the vet] said there is no real reason at this time for the unicorn tail to be removed.”

The tail doesn’t seem to bother Narwhal, nor does it slow him down, and it was confirmed, Narwhal does not have the ability to wag his tail on his head.

Narwhal has gained a lot of attention on social media, with many people showing genuine interest in adopting him, however Mac’s Mission is not currently taking adoption applications.

“We are not accepting applications for him right now until we are very certain his unicorn horn is not going to have a growth spurt and become an issue,” the Facebook page said.

Mac’s Mission started in Rochelle Steffen’s kitchen, making shirts to fund Mac the pitbull’s surgery in 2012, after rescuing him in 2011.

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