Aquarium welcomes Yoko the baby shark after mystery pregnancy

A Louisiana aquarium welcomed a baby shark born under mysterious conditions, the aquarium said Friday. 

The swell shark, nicknamed Yoko, hatched on Jan. 3, according to the Shreveport Aquarium. What makes the birth mysterious is that the tank is home to two female sharks who haven't been in contact with a male in over three years. 

"This situation is incredible and shows the resilience of this species," Greg Barrick, the curator of live animals at Shreveport Aquarium, said in a news release.