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Charlotte ray in her aquarium: no flirting with other fish

Photo: Aquarium and Shark Lab / Team ECCO / AP

Actually, the matter is clear: without males, there can be no offspring. But that's exactly what's happening in the USA at the moment. Stingray lady Charlotte lives in an aquarium in North Carolina - without a male of the same species for at least eight years. And yet the aquarium now says: Charlotte is pregnant with up to four young animals and could give birth in the coming days.

Whether there is a father and who that could be is currently unclear - and stimulates the imagination of some people. There is some speculation about parallels to the Christmas story. Will little Jesus rays soon see the light of day here? Fortunately, there are also attempts at explanations that should be taken more seriously.

Charlotte shared the tank with about five small sharks. However, scientist Kady Lyons from the Georgia Aquarium in Atlanta believes that mating with the animals is almost as impossible as a second Christmas story. Apart from the fact that the animals are different sizes, they do not fit together anatomically and their DNA is also not compatible. "We should make it clear that there was no shark-ray mischief going on here," Lyons said.

Initially suspected of a tumor

Parthenogenesis would be another explanation. This refers to unisexual reproduction in which the offspring develop from unfertilized eggs. A male is not necessary for this type of reproduction. The phenomenon is known from insects, birds and reptiles. Parthenogenesis has also been demonstrated in other ray species. However: According to Lyons, the method of reproduction of stingrays, which belongs to the Charlotte species, is not yet known.

Nevertheless, the expert considers the option to be conceivable. "I'm not surprised because nature always finds a way," Lyons said. But: "We don't know why this happens." Unlike most other fish, stingrays do not lay eggs but give birth to live young.

Charlotte currently lives in a tank about the size of a construction container. If everything goes well, she should move soon, explains Brenda Ramer, managing director of the aquarium where the animal lives. After all, there should also be room for the next generation. And people should also benefit - the development of the new family should be broadcast live.

It is said that no one in the aquarium initially thought that Charlotte could even be pregnant. Why? Initially, experts assumed there was a tumor on her back. An ultrasound would then have given the all-clear and revealed the pregnancy. “We thought we were overfeeding them,” said Ramer, looking at the pregnant ray. "But she just has more mouths to feed."