a ray living in an aquarium is expecting babies… without having been in contact with a male

The ability to reproduce without the genetic contribution of a male has long been considered extremely rare, but has been observed in recent years in many vertebrates.

A mysterious “virgin birth” ? A stingray living in a small town aquarium in the United States is expecting babies without ever having shared her tank with a male of her species, making her a local sensation and a scientific curiosity.

Charlotte, who has been staying in Henderson, North Carolina for more than eight years, began developing an unusual lump in late November. The aquarium teams initially feared that it was a tumor. “Her bump started growing and growing, and we thought it might be cancer.”, Kinsley Boyette, caregiver and deputy director of the institution, told AFP. Such cysts are known to be able to develop in the reproductive organs of non-mating rays.

But after an ultrasound, the good news comes: it’s actually eggs. Charlotte the skate could give birth any day now. Such “virgin births” are rare and the gestation period can vary and is not necessarily three to four months as usual.

A rare phenomenon but already observed

The ability to reproduce without the genetic contribution of a male has long been considered extremely rare, but has been observed in recent years in many vertebrates, including birds, reptiles and fish, but not in mammals. Animals that cannot mate will sometimes carry out this process called parthenogenesis.

Small cells called polar bodies, formed at the same time as the eggs and which normally disintegrate, then fuse again with the egg, providing the genetic material needed to create a viable embryo.

It’s hard to know how often this happens. A case involving a shark or ray in an aquarium is reported every year or two. It could be that this also occurs in nature, but only genetic testing could confirm this.