A stingray from an aquarium in North Carolina got pregnant without a male mate. There were speculations that her pregnancy was a case of Immaculate conception, just as how the Virgin Mary conceived Jesus Christ, but marine experts argued.
Charlotte The Stingray's Pregnancy Explained
Charlotte, the pregnant stingray, is on display at the Aquarium & Shark Lab in Hendersonville, North Carolina. She got pregnant without a male mate and was expecting four pups.
Initially, there were speculations that she got impregnated by a white-spotted bamboo shark, which was in the tank between her and sharks, and rays can store sperm for at least up to a year. However, experts don't think this was the case because Charlotte has already been on her own for too long.
Dr. Christopher Lowe, a professor of marine biology and director of the Shark Lab at California State University, discussed Charlotte's case. According to him, stingrays like Charlotte can get pregnant in two ways. The first one was what we previously mentioned, but the second one—parthenogenesis—was a more sound explanation of Charlotte's pregnancy.
"It turns out that parthenogenesis is more common in sharks and rays than we previously thought, so this is the most likely explanation," Lowe said, noting that this can easily be confirmed by doing a quick DNA test if she gives birth to a "viable young."
While parthenogenesis is not uncommon, according to Kevin Feldheim, a Chicago's Field Museum researcher, Charlotte's case is the first time the process has been documented in her species, making it the 15th species to be documented altogether.
The aquarium monitors Charlotte's condition daily and states that she is carrying up to four pups despite no visible signs of them yet. The team hasn't been able to confirm Charlotte's estimated delivery date, though.
Lowe states this is most likely because it's unclear when she began producing an embryo and whether lengthier gestation times are necessary for parthenogenesis. Compared to other species, round stingrays usually have a shorter gestation time; the length of their pregnancy varies from three to four months, depending on the water's temperature.
Lowe stated, "the more and longer some species are kept in captivity, the more we learn about oddities like this."
What Is Parthenogenesis?
Parthenogenesis is a method of reproduction wherein an egg can grow into an embryo without the need for sperm fertilization. The term parthenogenesis is Greek for "virgin birth," it is a reproductive strategy used by several insect species, such as ants, bees, and aphids. Parthenogenesis has drawn much interest lately as a means of producing stem cells.
It is rare in higher vertebrates but frequent in lower plants and invertebrate creatures (especially rotifers, aphids, ants, wasps, and bees). Parthenogenetically generated eggs can be diploid (having a paired set of chromosomes) or haploid (having one set of different chromosomes). Parthenogenic species can be facultative, meaning they can alternate between parthenogenesis and sexual reproduction, or obligatory, meaning they are incapable of reproducing sexually.
In Charlotte's case, sharks and stingrays reportedly frequently undergo parthenogenesis when kept in isolation for an extended length of time. This process enables them to create clones.
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