Virgin Birth: Chicago Zebra Shark Gave Birth Asexually Inside Aquarium

A Chicago zebra shark gave a virgin birth inside an aquarium, according to a study published on November 12.

The shark mysteriously underwent an asexual reproduction even with the presence of other male sharks and even without having sexual intercourse with any of them, scientists confirmed.

Chicago Zebra Shark

(Photo : ANTONY DICKSON/AFP via Getty Images)

A study published in the Journal of Fish Biology highlights a case of parthenogenesis or asexual reproduction involving a female endangered zebra shark located at Shedd Aquarium in the city of Chicago in Illinois, United States.

The female shark gave birth to an offspring without having mated despite the presence of healthy males inside the same tank.

The study considered the incident to be the second instance of parthenogenesis involving a zebra shark female that was housed with mature males.

Researchers said that most cases of asexual reproduction have occurred whether females were enclosed without males or once a male was removed from a females' tank or aquarium.

Also Read: Your Vacation Photos of Whales and Zebras on Social Media Helps Scientists!

What is a Zebra Shark?

A zebra shark (Stegostoma fasciatum) is a species under carpet sharks and the only member of the family Stegostomatidae and a member of the order Orectolobiformes.

The shark species is known for being solitary but sometimes mix in an aggregate group of 20 to 50 individuals.

They are found across the tropical Indo-Pacific, often found at coral reefs and sandy parts of the oceans.

Being a nocturnal animal, zebra sharks reportedly hunt small fish, crabs, small fish, snails, sear urchins, and other small invertebrates hiding out in crevices.

During daytime hours, zebra sharks rest on the ocean flood facing the current so it would be easier to pump water through their gills.

According to Oceana, a non-profit ocean conservation organization, S. fasciatum carry out their reproduction when males transfer sperm to the females or alterations of the pelvic fins; where a female zebra shark can lay up to four egg at a given time.

In addition, the said non-profit organization provides the following facts about zebra sharks:

Zebra sharks are typically found over sand, particularly near coral reefs and rocky reefs as deep as 203 feet.
They can reach a maximum length of about eight feet and live over 28 years in an aquarium.
They are sometimes confused with leopard sharks because they are born with dark brown with white bars colors throughout their bodies.
Zebra sharks are mostly found living in marine water but have been seen before in brackish and freshwater habitats.
They can squeeze into narrow spaces to search for food.

What is Asexual Reproduction?

A 2008 study published in the journal Nature Education states that sexual reproduction is common, and that researchers estimated that more than 99.99% of eukaryotes, which are single-celled or multicellular organisms, reproduce sexually.

The study's researchers that birds, bees, and most living life forms need their mates to have their offspring.

On the other hand, asexual reproduction is a different story since it does not rely on the conventional male and female sexual intercourse in order to have an offspring.

However, the researchers point out that asexual reproduction is easier compared to its counterpart since the latter requires more resources.

Sexual reproduction also reportedly poses the risk of genetic defect due to genetic recombination.