crocodile virgin birth in costa rica: Crocodile’s unfertilized birth is a first for the science history books. international news in hindi

crocodile virgin birth in costa rica: Crocodile’s unfertilized birth is a first for the science history books.  international news in hindi

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Nottingham (UK). Stories of having children without fertilization have been told throughout history. The ancient Roman god Mars, the ancient Egyptian god Horus, and those from ancient Chinese mythology were all born of virgin mothers. But birth without fertilization does indeed happen in the natural world.

The first evidence of birth without fertilization in crocodilians was reported in an American crocodile, Crocodylus acutus, which had been kept in a zoo in Costa Rica for 16 years. She laid 14 eggs, seven of which seemed viable and were inseminated artificially.

The eggs hatched unsuccessfully and six of them hatched. But one had a fully formed fetus, which was genetically identical to its mother, showing no evidence of bonding with any male during this time. This is not the first case of celibacy in the animal kingdom. Baby lizards, snakes, sharks, and birds, including the California condor, have all been documented from unfertilized eggs. How do we explain virgin births?

Species can reproduce either sexually, combining genetic material from the two parents, or asexually. Our ancient ancestors were asexual and essentially cloned themselves. Plants reproduce in a similar way, involving division, budding, and fragmentation. However, this produces many organisms that are genetically identical, and the lack of genetic variation means that individuals cannot adapt to changing conditions. Can be

If the environment is bad for one member of a species, it is bad for all, and can lead to extinction. Sexual reproduction in species such as humans requires sperm to fertilize an egg and form an embryo. . In terms of evolution, sexually reproducing species are considered more advanced, as their offspring are genetically diverse, with unique gene combinations from their parents. This diversity can be important if a species is to adapt. be required. It also reduces adverse genetic mutations, which are often associated with inbreeding (when close relatives mate).

The American alligator swimming in a river in Costa Rica was one such American alligator. Uwe Bergwitz/Shutterstock Virgin births are a form of asexual reproduction because they do not require genetic traits from sperm. But, unlike other forms of asexual reproduction, they do require an egg. Unfertilized eggs are often produced by the female—you may have had unfertilized eggs from a house hen for breakfast this morning—and if unfertilized eggs are not eaten, they eventually perish. But there is one exception. Birth without fertilization, known as parthenogenesis, occurs when an unfertilized egg develops into an embryo.

It is not necessarily genetically identical to the mother – it depends on how the egg cell develops. Parthenogenic children can be either full or half clones of the mother. Half clones are produced when embryonic cells split in half before multiplying. Full clones are formed when an embryo multiplies complete cells. Therefore half clones have less genetic diversity than full clones. Not only do they lack the genetic diversity of organisms created in sexual reproduction, but they also inherit only about half of their mother’s genetic diversity.

Some species, called facultative parthenogens, alternate between sexual and asexual reproduction. They mainly rely on sexual reproduction, but can use asexual reproduction if necessary. Birth without fertilization, which usually results in female offspring, is thought to trigger many conditions. For example, when there are not many males around. It is often reported in caged animals, including bonnethead sharks, where the animals are kept in single-sex enclosures. gene transfer

Even when males are around, females can use parthenogenesis. For example, last year a female zebra shark gave birth to multiple babies with DNA that didn’t match any of the males at the Chicago Aquarium where she lived. This phenomenon astonished the researchers. Perhaps the female did not like the people she lived with. If the environment is poor, asexual reproduction involves less effort than sexual reproduction, as the female does not need to waste time and energy searching for mates. .

For example, many cases of parthenogenesis have been discovered in geckos, snakes and lizards that live in dry and harsh climates such as high altitudes.
Females can also reproduce asexually to take advantage of favorable changes in conditions. The spiny-cheek crayfish is native to the Americas, but was introduced to Europe where the climate is temperate. It has reached many European waterways by reproducing asexually. Although many invasive species are larger and stronger than natives, parthenogenesis is another factor that may contribute to their success.

Genetic testing techniques that can more easily identify parthenogenesis are helping researchers discover that more and more species are capable of producing children without fertilization. The revelation of parthenogenesis in the American crocodile suggests that there is a common ancestral link between archosaurs, or proto-reptiles, including dinosaurs, pterosaurs (flying reptiles), birds and crocodiles. Since parthenogenesis occurs in birds and crocodiles, it is possible It is believed that even in dinosaurs birth took place without fertilization.

A pregnant crocodile without fertilization is eerily reminiscent of a scene in Jurassic Park when scientists claimed there was nothing to worry about, as they could control the park’s population by making sure all dinosaurs produced females, so naturally No babies will formally be born. But in the words of the film’s chaos theorist, Dr. Ian Malcolm (played by Jeff Goldblum): “Life just finds its way.

Pc:Navbharat Times



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