Yoko is believed to be the result of parthenogenesis, a rare type of asexual reproduction where offspring develop from unfertilized eggs.

On January 3, the Shreveport Aquarium in Louisiana welcomed a swell shark pup into the world under mysterious circumstances: It was born in a tank that housed only two sharks—and both were female. The two swell sharks have been in a female-only habitat at the Shreveport Aquarium for more than three years.

A small shark swimming around a Louisiana aquarium holds a mystery in its DNA. Yoko the swell shark hatched from an egg that was discovered in a puzzling place — an all-female tank, the Shreveport Aquarium announced. “It really proves that life ... uh ... finds a way,” curator Greg Barrick said in a Jan. 24 news release.

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,

Life truly foudn a way inside of an Louisiana aquarium earlier this month when a baby shark was born inside a tank that only is home to only female species. At such a critical moment in US history, we need reporters on the ground. Your donation allows us to keep sending journalists to speak to both sides of the story.

Yoko, a swell shark (Cephaloscyllium ventriosum) was born in a tank inhabited solely by two adult females. The team confirmed that the two female sharks in the tank had not interacted with a male for over three years.

The Shreveport Aquarium in Louisiana is investigating the mysterious birth of a baby swell shark, despite no male sharks being present in the tank for three years.

The pup hatched in a tank housing two female sharks who hadn't been around any male sharks in over three years.

When a shark egg appeared one day in a shark tank at a Louisiana aquarium, staff were puzzled. That’s because the tank only has two sharks in it — and they’re both female.