Baby shark mysteriously hatches from egg at Louisiana aquarium — with no male in tank

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.

An aquarium employee discovered the egg in a tank containing two female sharks about eight months before it hatched, although staff isn’t sure when it was laid, the aquarium shared.

Staff members quarantined the egg as it developed until Jan. 3, when they assisted in hatching it.

“Sharks can get stuck in their eggs sometimes so we used some scissors and cut it open very carefully,” Barrick told the Australian Broadcast Corporation. “And then when I opened up the egg it swam off, and we were super excited to see that.”

Aquarium staff confirmed neither of the female sharks in the tank had been around a male in over three years.

“This does suggest that either a phenomenon called parthenogenesis, a rare form of asexual reproduction, or delayed fertilization, where fertilization occurs long after mating, may have occurred,” aquarium officials said.

But they won’t know the answer until the pup is big enough to give a blood sample, which likely won’t be until it’s a few months old. At that point, the husbandry team will conduct a karyotype to look at the pup’s chromosomes and determine if the shark came from one parent or two.

“Parthenogenesis does end up having negative effects on an individual’s health just because of that lack of genetic diversity,” Barrick told the Australian Broadcast Corporation.

The aquarium is already preparing fans for the chance of a negative outcome but said so far, the pup is “thriving.”

“Should Yoko’s time with us be brief, it will still leave an unforgettable legacy, contributing invaluable insights to the study of shark reproduction and conservation efforts,” the aquarium said.

Parthenogenesis, also referred to as a “virgin birth,” is fairly uncommon in higher vertebrates such as sharks, although it does happen, according to National Geographic.

In 2023, an epaulette shark was born via parthenogenesis at Brookfield Zoo in Chicago to a female shark that hadn’t been around males in at least four years, McClatchy News reported.

Shreveport is in northwest Louisiana.

This story was originally published January 29, 2025 at 3:51 PM with the headline "Baby shark mysteriously hatches from egg at Louisiana aquarium — with no male in tank."