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Female Shark Learns To Reproduce Without Males After Years Alone (newscientist.com)
An anonymous reader quotes a report from New Scientist: A female shark separated from her long-term mate has developed the ability to have babies on her own. Leonie the zebra shark (Stegostoma fasciatum) met her male partner at an aquarium in Townsville, Australia, in 1999. They had more than two dozen offspring together before he was moved to another tank in 2012. From then on, Leonie did not have any male contact. But in early 2016, she had three baby sharks. Intrigued, Christine Dudgeon at the University of Queensland in Brisbane, Australia, and her colleagues began fishing for answers. One possibility was that Leonie had been storing sperm from her ex and using it to fertilize her eggs. But genetic testing showed that the babies only carried DNA from their mum, indicating they had been conceived via asexual reproduction. Some vertebrate species have the ability to reproduce asexually even though they normally reproduce sexually. These include certain sharks, turkeys, Komodo dragons, snakes and rays. However, most reports have been in females who have never had male partners. In sharks, asexual reproduction can occur when a female's egg is fertilized by an adjacent cell known as a polar body, Dudgeon says. This also contains the female's genetic material, leading to "extreme inbreeding", she says. "It's not a strategy for surviving many generations because it reduces genetic diversity and adaptability." Nevertheless, it may be necessary at times when males are scarce. "It might be a holding-on mechanism," Dudgeon says. "Mum's genes get passed down from female to female until there are males available to mate with." It's possible that the switch from sexual to asexual reproduction is not that unusual; we just haven't known to look for it, Dudgeon says.
It's the Messiah! Bow down before them and adore them!
My first program:
Hell Segmentation fault
"Life... Finds a way."
But has she figured out how to grow her own lasers yet?
Website Just Down For Me? Find out
She _learned_ it did she? Hopefully the same book that taught her about asexual reproduction doesn't have a chapter on lasers.
More ammo for the war on men....
Dude, if we could give ourselves blowjobs the species would have died out millennia ago.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Lesbian sharks are always relevant. If you don't like it, you need to address it directly with them.
BTW... Never, ever, tell an angry lesbian shark that she's wrong. Nothing good will ever come from it.
Serious? Seriousness is well above my pay grade.
The answer is (almost certainly) no. Parthenogeneses has never been observed in humans at all and has never been naturally observed in any mammal in fact. It does occur in some other species (fishes, reptiles and amphibians) but it is apparently impossible in mammals. The only cases in any mammals seen thus far were deliberately done by human intervention using the same types of techniques used for cloning.
Unicode killed the ASCII-art *
WTF? This has been known for decades.
I'm sure if you look at the WIkipedia article it has said this for at least several years...
Talk about Fake News.
Yes, perhaps it is better if you talk about fake news. This, however, is about science. I don't think I have read this particular article, but it has been mentioned in different places, and what is new, is the discovery that a female shark that has previously reproduced sexually, has been found to reproduce asexually several years later, which is a first. We had previously seen female sharks that grow up in captivity without males, can do this, but it was not obvious that this could also happen if they had mated in the past - it isn't unreasonable to think that mating might have triggered some mechanism - hormones or whatever - that would make asexual reproduction impossible.
No, but methinks they ARE working on a method using cats for reproduction. Because when a woman doesn't have a man, she INVARIABLY has at least one cat. . .
For human women. After parthenogenesis is perfected, Human males will become useless parasites, and can finally be eliminated, ending all of the problems on earth.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Because it is so dangerous for a man to get married and have children due to unfair family law. MGTOW. Look it up
While MGTOW is a little interesting, way too much of it is butthurt whining. But the point is taken that an increasing number of men who would make good mates for a woman have done a risk/benefit analysis, and decided that it is not worth it.
And that is kind of a problem. It's a passive avoidance, it isn't illegal. It's like avoiding smoking by not smoking. And as VR and "sex dolls" become more realistic, will only become worse.
What is worse, while stable prudent men decide to pursue their careers and keep their assets, and avoid relationships with females, the jerks and abusers won't change at all.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
My wife had the same thing happen to her as happened to that shark. I'd been working abroad 6 months and she managed to get pregnant completely on her own. Unbelievable.
He's getting rather old, but he's a good mouse.
No. It would be more like if you combined the genetic material of two eggs from the same mother together. It's a mish-mash of genes with a high degree of of similarity. So for example your odds of getting two copies of the same gene are greatly increased. This leads to a higher degree of birth defects and recessive gene combining in unpleasant ways. A clone would actually be *less* genetically damaged.
That being said, it probably works out more-or-less okay for one generation but much beyond that it quickly becomes unsustainable.