Posted on 10/10/2008 4:14:32 PM PDT by Libloather
'Virgin Birth' By Shark Confirmed: Second Case Ever
ScienceDaily (Oct. 10, 2008) Scientists have confirmed the second-ever case of a virgin birth in a shark, indicating once again that female sharks can reproduce without mating and raising the possibility that many female sharks have this incredible capacity.
Lead author Dr. Demian Chapman, shark scientist with the Institute for Ocean Conservation Science at Stony Brook University, Beth Firchau, Curator of Fishes for the Virginia Aquarium & Marine Science Center, and Dr. Mahmood Shivji, Director of the Guy Harvey Research Institute and Professor at Nova Southeastern University in Florida, have proven through DNA testing that the offspring of a female blacktip shark named Tidbit contained no genetic material from a father. Tidbit had lived at the Virginia Aquarium in the Norfolk Canyon Aquarium for eight years since shortly after her birth in the wild.
In May 2007, Chapman and Shivji were part of a team that made the groundbreaking scientific discovery confirming - for the first time ever -- a virgin birth in a female shark. That shark was a hammerhead residing at an Omaha, Nebraska zoo and had not been in contact with male sharks for at least three years. That study was published in the journal Biology Letters and captured global media and scientific attention. The DNA-fingerprinting techniques used to prove both cases of virgin birth (scientifically known as parthenogenesis) are identical to those used in human paternity testing.
It is now clear that parthenogenesis occurs in sharks other than just hammerheads, Chapman said. The first case was no fluke. It is quite possible that this is something female sharks of many species can do on occasion.
(Excerpt) Read more at sciencedaily.com ...
I don't think this story has any teeth.
I had always heard that it was something in the water.
Two possibilities if true: 1) parthenogenesis has been known to happen with low level species. so maybe hammerheads are less evolved than we think. 2) the female keep the male sperm inside her until needed, although three years seems too long.
But was it immaculately conceived? Big difference, and I ain’t worshiping no fish until it meets BOTH conditions. Got it?
The article addressed your second point
...have proven through DNA testing that the offspring of a female blacktip shark named Tidbit contained no genetic material from a father.
Well if they are looking for a name for the offspring, ‘Barack’ would be a logical choice.
How do we know that some lawyer didn’t sneak in one night and make whoopee with the female shark?
...and lesbians around the world have since been inquiring into gene therapy....
Struck me funny.
I’ve even heard of rare cases of it happening with humans, but I couldn’t confirm. What I have also heard is that whenever it happens, the offspring is ALWAYS female.
Yikes! Somebody post of picture of Sarah or Ann quick!
or....the democrats have found their new deity if Obama doesn’t win.
Damn Lawyers. You just can’t get rid of them totally...
I think I had read about some species of small marine creatures that will convert from male to female when the female population in their habitat becomes to small. I don’t know if it said the males were born with latent ovaries, or if some habitat triggered hormonal change causes the testes to make eggs (males do have the X chromosome) instead of sperm.
and, I ran across this:
“A few species are unisexual: there is no fusion of sperm and egg. A sperm cell is necessary to trigger an egg cell [zygote] to develop, but the sperm cell.........does not contribute genetic material. The resulting young always are females. Thus, unisexual species are entirely female. They mate with males of related species to produce female offspring. Poecilia formosa is an example of a unisexual species. Always female, P. formosa mates with male
P. mexicana or P. latipinna.”
at: http://www.seaworld.org/animal-info/info-books/bony-fish/reproduction.htm
Now, one must wonder what the females of “P. mexicana or P. latipinna” think of their rightful sperm donations being poached this way!!!!!
We will always need you. Somebody has to kill the spiders.
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