Every December, Christians around the world celebrate the birth of a baby to a woman who has never had sex.
We’ve seen the phenomenon of “virgin births” in pythons, turkeys, and even flies.
And just this week, a female crocodile gave birth to 14 fertilized eggs in Costa Rica, despite living alone for more than a decade.
But are “virgin births” really possible in humans?
MailOnline spoke to an expert to find out if this really is the beginning of the end for men.
Virgin births can occur in reptiles, fish, and even flies, but what about humans? (stock image)
How does a ‘virgin birth’ work?
Virgin birth is a natural process called facultative parthenogenesis, meaning that a female can produce young without the intervention of a male.
It is extremely rare in nature, although it is found in some other species, notably mayflies, tturkeys, pythons and boa constrictors.
In the crocodile’s case, it involved a mechanism called “terminal fusion automixis,” meaning the female fertilizes her own eggs using a genetic byproduct called the second polar body.
This means that both parents are the mother and they have two pairs of the maternal DNA.
Wildlife generally does not reproduce this way, but some research now suggests that endangered animals are more likely to do so as mating becomes more difficult.
Virgin birth, or facultative parthenogenesis, is a rare ability in some animals that allows the production of offspring without sex.
This is common in fish and reptile species, but scientists still don’t know what makes it possible.
“We still don’t really know exactly what makes virgin birth possible in some animals but not others,” Professor Russell Bonuriansky, an ecologist at the University of South Wales in Australia, told MailOnline.
“But we do have some idea of what it takes. A normal cell in your body has 46 chromosomes, 23 from the egg and 23 from the sperm. Other animals have different numbers, but usually half of the chromosomes come from the mother and the other half from the father.’
For humans to form a viable embryo without sperm, the egg would have to replicate its chromosomes to end up with the “normal” number.
The egg must also initiate a process of fertilization – which is usually the role of sperm – and develop the embryo.
But the odds of this happening may be one in a billionaccording to Stands – making it nearly impossible.
Professor Bonduriansky believes that this inability may also be associated with a protective mechanism.
“Some animals can do this, but for some reason most can’t,” he said.
“(It) works to prevent eggs from developing into embryos in the ovaries, which would be deadly to female mammals,” he continued.
‘However, scientists have devised ways to modify mammalian development so that unfertilized eggs can develop.
‘The most famous example is Dolly the cloned sheep. Artificial cloning is probably also possible in humans, but of course it raises complex ethical issues.’
Scientists have found the first known crocodile that produces self-fertilized eggs (stock image)
Despite its rarity, a strange case occurred in 1995, with a young boy believed to have come in part from an unfertilized egg.
As a result, the boy reportedly had an odd number of chromosomes, which would typically mean he was female, according to the New scientist.
But Professor Bonuriansky says this was not a true example of a virgin birth.
He told MailOnline: ‘This boy is an example of an extremely rare type of genetic mosaic. In humans, different body parts sometimes turn out to be genetically different due to accidents in cell division early in embryonic development, or due to the fusion of two embryos in the womb. For example, some cells may have an extra chromosome.
“This boy is very unusual in that some of his cells have no paternal genes at all. This may have happened because the sperm entered the egg after the first cycles of cell division had already spontaneously occurred.
‘As a result, some of his cells only contain genes from his mother. Nevertheless, his body has some cells with both maternal and paternal genes, so he’s not a true example of a virgin birth.’
The British medical journal also recorded about 45 bizarre ‘virgin pregnancies’ in the US since the mid-1990s.
While the women did not directly claim to have experienced this, they reported characteristics that were synonymous.
This followed a survey asking about vaginal intercourse and sexual history.
‘We weren’t looking for virgin births at all’ Professor Amy Herring at the Gillings School of Global Public Health in North Carolina, said.
“While analyzing data for a separate project examining correlates of virginity in adulthood, we were surprised to find that some of these individuals who reported being virgins also reported pregnancies.
“Once we confirmed that these were not programming errors, we became interested in understanding factors associated with this type of response pattern.”
Of the 7,870 women, 0.8 percent of those who got pregnant without sex said they hadn’t used birth technology to support their pregnancy.
But, more importantly, these results were not medically validated, which could indicate bias on the part of the respondents.
So what’s the biological point of sex if there’s an option to give birth alone?
Professor Jenny Graves of La Trobe University in Australia, said The conversation that parthenogenesis is actually worse in the long run because of disease risks.
She said: ‘The answer seems to be that while parthenogenesis works fine in the short term, it will always lose out in the long run, because recombining two genes per generation is a great way to mix up the combinations of proteins that pathogens see. to fetch.
‘A pathogen that can infect one individual can also infect others with the same genes, so it makes no sense to have many cloned copies. For example, the female-only Australian gecko is very susceptible to mite infestations.
“So the answer to the question of whether virgin birth is real is yes, unless you’re a mammal.”
HOW DO SPERM MOVE?
Sperm is vital in human reproduction and male cell motility is crucial.
To help the sperm move, they developed a “tail” called a flagellum.
The tails of sperm play a vital role in their ability to swim and consequently fertilize an egg.
Sperm is vital in human reproduction and male cell motility is crucial. The tails of sperm play a vital role in their ability to swim and consequently fertilize an egg
Sperm tails are made up of about 1,000 building blocks, including structures known as tubulins, which form long tubes.
Attached to these tubes are moving molecules called motor proteins.
These pull and bend sperm tails, allowing them to swim.
The movement of the tail is powered by a mitochondria, the powerhouse of a cell, which produces energy.