Yoko the swell shark was born in a habitat of all-female sharks who hadn't seen a male in years. The aquarium has two possible explanations — and hopes to get confirmation in the coming months.

According to the aquarium, the shark egg was first spotted eight months ago. The shark hatched a few weeks ago and the team at the aquarium is working to determine how it was conceived. Once the shark is big enough for a blood draw,

Last February, a similar situation occurred in Hendersonville, North Carolina, when a stingray at the Aquarium & Shark Lab was found to be pregnant despite living in a tank without a male of her species. The aquarium determined the stingray, Charlotte, had developed a rare reproductive disease that negatively impacted her reproductive system.

The female swell shark pup, nicknamed Yoko, hatched at the Shreveport Aquarium in Louisiana, despite no male sharks being present in the tank.

Nature is capable of some pretty incredible phenomena and even a few mysteries. That's become all the more apparent recently at Shreveport Aquarium in Louisiana, where the team is celebrating the hatching of an egg that seems to have only one parent.