Stingray Parthenogenesis

A North Carolina aquarium is home to the most remarkable stingray in the world. An adult female stingray called Charlotte is pregnant with four pups - without a male stingray to mate with in sight. At first it appeared Charlotte had a tumor, but on the eighth of February, scientists confirmed she was pregnant. According to the scientists managing the aquarium, she has not shared a tank with a male member of her species in at least eight years. There was speculation that she mated with one of the five sharks in her tank, but experts easily refute this theory because species cannot produce hybrid offspring with a species not closely related. The immaculate conception of Charlotte is rather a result of a phenomenon known as parthenogenesis, a form of asexual reproduction during which offspring develops from unfertilized eggs without genetic contribution by a male. These kinds of pregnancies happen most often in human care.

During the process of parthenogenesis, a female egg typically fuses with another cell known as a polar body and triggers cell division and the creation of an embryo. Parthenogenesis is a form of automixis; during an alternative form of this process, an egg cell will replace, reorganize and separate, while the polar bodies act as sperm and fertilize the egg. Dr. Dan Dombrowski, chief veterinarian at the North Carolina Museum of Natural Sciences in Raleigh, calls parthenogenesis a "stress response, or a way to save genetic material." It is known to occur in some insects, fish, birds and reptiles, such as California condors, Komodo dragons and yellow-bellied water snakes. 

Finley, B. (2024, February 14). Charlotte, a stingray with no male companion, is

     pregnant in her mountain aquarium. Phys.org. Retrieved April 5, 2024, from

     https://phys.org/news/2024-02-charlotte-stingray-male-companion-pregnant.html

Izlar, R. (2024, February 20). How a Stingray Likely Got Pregnant on Her Own.

     PBS North Carolina. Retrieved April 5, 2024, from https://www.pbsnc.org/

     blogs/science/how-a-stingray-likely-got-pregnant-on-her-own/