JPHiP Forum
General => General Discussion => Topic started by: chera on May 23, 2007, 09:27:02 PM
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Female hammerhead sharks can reproduce without having sex, scientists confirm.
The evidence comes from a shark at Henry Doorly Zoo in Nebraska which gave birth to a pup in 2001 despite having had no contact with a male.
Genetic tests by a team from Belfast, Nebraska and Florida prove conclusively the young animal possessed no paternal DNA, Biology Letters journal reports. (http://news.bbc.co.uk/1/hi/sci/tech/6681793.stm)
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This deserves an "Aw HELL NO!" Never liked sharks and now I like them even less. >:(
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so it's like natural cloning?
^lol wth, that doesn't really make sense at all. Why would you hate an animal more cause it reproduces asexually?
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Too bad the pub was killed by stingray. I didn't know that stingray can kill baby shark.
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Stingrays are freaking vicious. I wonder if the shark suddenly became dioecious...
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so it's like natural cloning?
The baby shouldn't be identical to the parent, unless it was also born the same way. So no, not cloning.
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Stingrays are freaking vicious. I wonder if the shark suddenly became dioecious...
You mean delicious, amirite?
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so it's like natural cloning?
The baby shouldn't be identical to the parent, unless it was also born the same way. So no, not cloning.
Wouldn't the pup have identical DNA as the mother though since it didn't have another shark to "mix" DNA with? I always assumed that's the same way cloning works, you get the DNA of an organism, and then you let the cells grow from that. I never really did any research on this kinda stuff other than high school biology so I really wouldn't know.
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Not with the type of reproduction that happened here. Explanation stolen from elsewhere since I'm too lazy to do it myself:
"The article claims only that the offspring is a perfect genetic "match" for the mom, not that it is identical to the mom since it also says the offspring has half the variability. What this means is the genetic test they did not pick up any polymorphisms not found in the mother. That's what they mean by "identical match".
Also parthogenesis does not create homozygotic offspring (although given enough generations it will), the immediate offspring is a result of a fusion event between 2 products of meiosis - the egg and one of the polar bodies. Thus the offspring will have a different genetic makeup to the mother. In particular half (on average) of the mother's heterozygous loci will become homozygous in the offspring. Thus the offspring has half the genetic variability."
So everywhere that had chromosomes AB has a 50% chance of still having that, and 25% chance each for AA and BB. If that baby has another one the same way then all of the AA and BB pairs will stay identical to the mother's ones but the AB pairs still have that 50% chance of changing. Repeat enough generations and you'll essentially have clones, with all the same AA and BB pairs and no AB pairs left.
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ahh sorta makes sense now lol
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lucky female human are not like those hammerhead sharks... if not life would be somehow broing for us guys...
if you get what i mean....
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Jesus Christ!