But in 2016, Leonie - who hadn't been introduced to another male - laid eggs which produced hatchlings, reports New Scientist. Over the course of six years, Leonie the zebra or leopard shark had produced more than two dozen offspring before she was separated from her mate in 2012. (NEWSER)– Australia's Reef HQ aquarium had hoped to scale back its shark breeding program. "This discovery throws a wrench in what we thought we knew about how and why parthenogenesis happens, and it illustrates a key aspect of science: We're continually learning.Watch Video: Shark has babies without mating "This is only the second case that we know of where sharks have been born by parthenogenesis even when there were healthy mates available," Feldheim said. While this phenomenon has previously been seen in sharks, it is rare, and even rarer to be seen when males are available to mate with. "They only have DNA from her, but it's recombined differently in the offspring, which is why parthenogenesis offspring are often unhealthy, even if the mom is fine," Kate Golembiewski, the PR and science communications manager at the Field Museum, told Newsweek. Despite the absence of males, the female lizards still undergo mating behaviors with each other to stimulate hormonal cycles prompting egg-laying. Some species, including the New Mexico whiptail, reproduce exclusively by parthenogenesis, meaning that they have not had males for millions of years. Various types of reptile, including species of whiptails, geckos, rock lizards and snakes have been observed to reproduce occasionally via parthenogenesis. KpTF90dCwS- Vagina Museum August 16, 2021 But a female komodo dragon who reproduces asexually can only create male babies, because nature is weird like that. Komodo dragons are one of a handful of vertebrate species who are capable of parthenogenesis - "virgin birth" - as well as sexual reproduction.
But they did match the female that laid the eggs," Kevin Feldheim, a researcher at Chicago's Field Museum and the lead author of the study, said in a statement.Īnother case of a shark "virgin birth" occurred in an Italian aquarium in 2021, where a female smoothhound shark gave birth to a baby despite having spent 10 years sharing her tank with only one other female shark. "These pups didn't match any of the mature males that were in the enclosure. However, one clutch of eggs confused the scientists, as it only contained the genetic information of one of the sharks, not two. The researchers found out that the Chicago zebra sharks were giving birth via parthenogenesis after genetically testing the offspring, which was originally meant to help the successful breeding of the endangered species. Virgin birth, or parthenogenesis, is the process in which organisms, usually vertebrates (animals with backbones), reproduce asexually, by giving birth to young using an unfertilized egg cell in a female animal. Shedd Aquarium / Brenna HernandezĪsexual reproduction is a common method of making new individuals across all of life: bacteria, plants, fungi and less complex animals frequently use this method of reproduction. A shark has been born at Shedd Aquarium in Chicago via parthenogenesis, with the mother giving birth to an asexual genetic clone of herself, despite there being males in the tank. An adult zebra shark (left) and a juvenile (right).
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