Follow Slashdot blog updates by subscribing to our blog RSS feed

 


Forgot your password?
Close
typodupeerror
×
Biotech Science

Female Sharks Can Reproduce Alone 293

Posted by Zonk from the i-thought-the-federal-government-banned-cloning dept.
mikesd81 writes "The Washington Post has an article about a team of American and Irish researchers that have discovered that some female sharks can reproduce without having sex, the first time that scientists have found the unusual capacity in such an ancient vertebrate species. Their report concludes that sharks can reproduce asexually through the process known as parthenogenesis (the growth and development of an embryo or seed without fertilization by a male). Scientists started investigating after a female hammerhead shark was mysteriously born at Omaha's Henry Doorly Zoo in a tank that housed 3 female sharks. It was originally thought one had stored sperm from a male shark before fertilizing an egg. However, baby shark's genetic makeup perfectly matched one of the females in the tank, with no sign of a male parent."
This discussion has been archived. No new comments can be posted.

Female Sharks Can Reproduce Alone More

Female Sharks Can Reproduce Alone

Comments Filter:

  • Sigh. (Score:4, Funny)

    by grub ( 11606 ) <slashdot@grub.net> on Wednesday May 23, 2007 @10:45AM (#19238119) Homepage Journal

    Female Sharks Can Reproduce Alone

    If male sharks had ST:TNG on DVD they'd be indistinguisable from human male geeks.

    • Re: (Score:2, Funny)

      by Anonymous Coward
      Well, at least this research explains how there came to be so many lawyers in the world.

      • Female Sharks Can Reproduce Alone (Score:5, Funny)

        by mollog ( 841386 ) on Wednesday May 23, 2007 @12:13PM (#19240325)
        Female Sharks Can Reproduce Alone
        So you've met my ex-wife?

        Seriously, imagine the shark husbands; "That's not my pup. Who's the father???"

        Or trying to explain this to your parents; "But Mom, I didn't. Really Mom."

        And now the quotes, "A female shark needs a male shark, like a flounder needs a bicycle." - "All he's good for is opening jars and lifting heavy things." - "Not tonight, honey. I'm already stuffed."

        In some ways, it would suck to be a male shark.

  • Necessary improvement (Score:5, Funny)

    by 6Yankee ( 597075 ) on Wednesday May 23, 2007 @10:46AM (#19238137)
    They were forced to evolve this ability after all the males were killed in frickin' laser accidents during mating attempts.

  • All the geeks ... (Score:3, Funny)

    by eck011219 ( 851729 ) on Wednesday May 23, 2007 @10:46AM (#19238141)
    ... at splashdot.org were just ruled obsolete. Slashdotters, beware ... we're next!

    • Re: (Score:2)

      by Kjella ( 173770 )
      Sure, as long as people don't want to have sex for other reasons than reproduction. *looks in the mirror* ...and maybe a few other reasons too.
    • If Slashdotters don't figure out a way to reproduce alone, they'll be worse than obsolete, they'll be extinct. We sure as hell won't find anyone else who'll reproduce with us.
    • It as if millions of voices suddenly cried out in terror and were suddenly silenced. I fear something terrible has happened. The entire splashdot community dissapeared [splashdot.org].

  • Note to self... (Score:5, Funny)

    by Steve--Balllmer ( 1070854 ) on Wednesday May 23, 2007 @10:46AM (#19238149)
    don't clone dinosaurs using shark DNA.

  • Womyn rejoice! (Score:5, Funny)

    by R2.0 ( 532027 ) on Wednesday May 23, 2007 @10:47AM (#19238151)
    Finally, proof that Mother Nature never intended males to exist at all.

    • Re: (Score:3, Funny)

      by cayenne8 ( 626475 )
      "Finally, proof that Mother Nature never intended males to exist at all."

      Sure you might think that, but, without us...who'd mow the lawn, or kill the big scary spider?

      :-)

      On the other hand...the only reason we talk to ya'll...is because you have tits.

    • Re:Womyn rejoice! (Score:4, Interesting)

      by garett_spencley ( 193892 ) on Wednesday May 23, 2007 @10:59AM (#19238451) Journal
      I realize that was intended as a joke, and I am not an evolutionary biologist, but wouldn't this type of reproduction completely eliminate the possibility for evolution ?

      I don't mean to imply that this is evidence contradicting the occurrence of evolution, just that if animals were to reproduce asexually, and thus essentially be clones of their parent, then evolution is not possible for that particular species ?

      So what are the benefits ?

      • Re:Womyn rejoice! (Score:4, Informative)

        by Rycross ( 836649 ) on Wednesday May 23, 2007 @11:07AM (#19238637)
        No, it wouldn't eliminate it. Its more accurate to say it would slow evolution. After all you'll still get mutations, and you'll still get selection from the environment. It just lowers the diversity and a big selection pressure (getting chosen as a mate). There was a time when asexual reproduction was the norm (bacteria, single-celled life forms), and you can see for yourself the result of that.
        • It wouldn't necessarily slow evolution, but it may speed it up. Species exist in populations that are distributed throughout a landscape and natural selection acts directly on a gene's phenotype. Therefore, if a sub-population of a species happens to have greater fitness due to a trait that is best maintained by asexual reproduction, it is possible that that sub-population may quickly diverge from the greater population.
      • It just rules out the ability for beneficial mutations to be acquired from different lines.

        Viruses don't have sexual reproduction, yet they mutate and form resistant strains.
      • The benefit is that they can reproduce without a mate, not that they have to. Obviously to have diversity in the species, mating is necessary, but it's better to have offspring with no diversity rather than no offspring at all. This type of reproduction is good as a last resort, not as the norm.

      • Re: (Score:2)

        by hoggoth ( 414195 )
        > wouldn't this type of reproduction completely eliminate the possibility for evolution ?

        Not completely. Clearly the ability to reproduce sexually EVOLVED from organisms that existed before sexual reproduction. But correct in that asexual reproduction can only evolve through extremely slow random mutations. Sexual reproduction allows a very fast way to 'try all the variations' of a gene pool and thus find local optimums for existing conditions.

        I imagine that sexual reproduction, for example, allows a spe

        • Clearly the ability to reproduce sexually EVOLVED from organisms that existed before sexual reproduction. But correct in that asexual reproduction can only evolve through extremely slow random mutations.


          Or the insertion of DNA from, e.g., viruses.
      • Natural selection has little to do with sex. Sexual reproduction speeds up the process among complex organisms, but bacteria evolve very quickly without it.

        • Re:Bacterial Conjugation (Score:3, Informative)

          by jc42 ( 318812 )
          Sexual reproduction speeds up the process among complex organisms, but bacteria evolve very quickly without it.

          Sure they do. Google for "Bacterial Conjugation". Of course, they don't have genitalia like we do, but they manage anyway. Pretty much all bacteria that have been studied in any depth have been found to use conjugation to exchange DNA. There's even "bacterial porn" online, videos of the conjugation process.

          Actually, most of them only engage in sex occasionally, Mostly they reproduce by cloning
    • Finally, proof that Mother Nature never intended males to exist at all.

      Don't get too excited, women are still going to need us to get the lids off of jars and reverse the car out of the driveway.
    • There was a science fiction story where a spaceship jumped into the future after going around the sun to find an Earth where only the women survived and the all-male crew became a scientific curiousity. Really, if it wasn't for the spermies providing the other half of the genetic diveristy, women don't need men that much for anything.
      • I remember it, it ended badly too - of course, in these stories, the men are always shown to be power-crazed sex maniacs who can't sit still without fighting something over someone. you never read sci-fi stories where an all-women crew spend all the time bitching, backstabbing and gossipping, but I suppose all these stories are written from an insecure male perspective.

        C.J. Cherryh did write a story about male/female role reversal though - the Chanur series. Basically took the idea of 'lions in space' where
  • ...have you been splicing in frog DNA [imdb.com] again? Naughty naughty.

  • Maintenance payments (Score:4, Funny)

    by Dude McDude ( 938516 ) on Wednesday May 23, 2007 @10:49AM (#19238209)
    I bet this bitch shark names an innocent male as the father, and the courts force him to pay $2000 in maintenance every month! Fuck!
  • ...why we refer to attorneys... you know, those nice folks who would prosecute and litigate issues of paternity and whatnot... ...as "sharks"?

    • ...why we refer to attorneys... you know, those nice folks who would prosecute and litigate issues of paternity and whatnot... ...as "sharks"?

      You're mistaken there. Lawyers don't reproduce asexually. But they do kill and consume their mother when they emerge from the womb.

      Joke as Corollary: "It is possible to get pregnant resulting from anal sex. This is how lawyers are born."

  • That's why they keep blowing me off in bars (Score:4, Funny)

    by jfengel ( 409917 ) on Wednesday May 23, 2007 @10:50AM (#19238255) Homepage Journal
    "She must be a dyke," I'd say.

    "No, that's just wishful thinking," my wingman tells me. "Maybe you should change your socks more often."

    Shows him!

  • Parthenogenesis does not create a clone (Score:5, Informative)

    by Anonymous Coward on Wednesday May 23, 2007 @10:51AM (#19238273)
    the baby should not have been genetically identical to anything in the tank unless its mother was also a parthenogen. parthenogenesis creates a homozygotic offspring that can have any random mix of the two chromosomes the mother carries for each pair. so if the mother has AB, the parthenogenic offspring can have either AA or BB, which is not identical to the mother since the mother has AB. the only way it can be identical is if the mother is also homozygotic and therefore a parthenogen.

    • MOD PARENT UP (Score:5, Funny)

      by Scooter's_dad ( 833628 ) on Wednesday May 23, 2007 @11:05AM (#19238585)
      For clearing up a common mis-"conception."

      And for not making a lame joke about parthenogenesis like I just did.
    • Interesting. Also, from TFA:
      This, in turn, would result in "genetically disadvantaged offspring,"

      I don't see how clones are necessarily genetically disadvantaged. If you have good genes to begin with then there is no harm in passing on those genes to your clone. Even over millions of years natural selection will still occur and random mutation will introduce genetic variety into clones. I doubt sharks have evolved much in the past million years, why would they be rapidly evolving in the next million yea

      • why would they be rapidly evolving in the next million years?
        They need to evolve somewhere to mount the fricken lasers and the power packs for stealth mode.

    • Re:Parthenogenesis does not create a clone (Score:5, Informative)

      by ozborn ( 161426 ) on Wednesday May 23, 2007 @12:05PM (#19240121)
      determined that a byproduct formed when sharks produce eggs, known as a sister polar body, had fused with an unfertilized egg to produce the baby shark, whose DNA had only half as much genetic variability as the mother.

      You've misread the article (which in fairness was not precisely written) and you're misunderstanding how parthogenesis is working here. 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.

      This has potentially bad consequences because of the # of recessive lethal alleles the average organisms carry. Think of parthogenesis as the worst form of incest possible.

    • Re: (Score:2)

      by Sparr0 ( 451780 )
      The summary did not say identical, it said no sign of a male parent. That doesn't mean that every gene was the same, just that every gene was a valid result of the mother's two chromosomes. If the mother is AA and the child is AB, then we would have reason to suspect another parent.

  • Big Deal (Score:5, Funny)

    by Anonymous Coward on Wednesday May 23, 2007 @10:53AM (#19238335)
    My wife does this

    Not sure why the kids are black tho
  • The shark just ate the stork...nothing to see here

  • A virgin birth after all (Score:5, Funny)

    by smooth wombat ( 796938 ) on Wednesday May 23, 2007 @10:55AM (#19238349) Journal
    Now we know how mankind really evolved. First there was the virgin birth, then we crawled out of the sea and after a few millenia, started to walk upright.

    Er wait, I'm confused.
  • How does this effect biodiversity. Thought one of the benefits of having multiple sexes was to insure a genetic mixup so that a single strain of genes doest become to prominent and things like bacteria/virii that adapt to that single code isn't as effective. Interesting post though.

  • On Henry Doorly (Score:5, Interesting)

    by ender81b ( 520454 ) <wdinger@g m a il.com> on Wednesday May 23, 2007 @10:56AM (#19238389) Homepage Journal
    Just a quick note, if you are ever in the Omaha, Nebraska area definitely stop by Henry Doorly Zoo [omahazoo.com]. It's probably the nation's second best zoo behind San Diego's, and the shark tunnel is fantastic. As are the penguins, and the desert dome, and indoor jungle, and... A few winters ago we went to the Zoo and the place was deserted. Was able to just lay down in the Shark Tunnel [omahazoo.com] and watch the sharks swim overhead for about a half hour with no one coming down. Was fantastic. At any rate, also -- as far as the article goes -- I wish someone would have some more explanation for how this works. Kindof freaky.

  • The Immaculate (Score:5, Funny)

    by poor_boi ( 548340 ) on Wednesday May 23, 2007 @10:57AM (#19238411)


    They should name the baby shark "Jesus." I think that would be kind of funny.



  • Great Whites? (Score:5, Informative)

    by JRGhaddar ( 448765 ) on Wednesday May 23, 2007 @10:58AM (#19238425)
    This is actually really interesting, and makes a lot of sense. Shark's genetics haven't evolved that much from its ancient relatives so this reproduction method would definitely limit variations. But I am curious as to if this is how the great white reproduces. Very little is known about the great whites breeding habits. One of the prevailing theories centers around whale carcasses. [youtube.com]

  • So.. (Score:5, Funny)

    by DeeVeeAnt ( 1002953 ) on Wednesday May 23, 2007 @10:59AM (#19238439)
    Nobody jumped the shark then?

  • Scientists started investigating after a...shark was mysteriously born at Omaha's Henry Doorly Zoo in a tank that housed 3 female sharks...with no sign of a male parent."


    Has anyone looked into the possibility that this infant shark is the Great White Jesus? (I'd hate to be the angel that messed up the avatar selection for the second coming.)
  • Finally, a story where the "sharks" tag is actually relevant. Of course ... now people are going to tag it with "lasers".

  • Sharks.... (Score:5, Funny)

    by curecollector ( 957211 ) on Wednesday May 23, 2007 @11:05AM (#19238571)
    ...can go fuck themselves.
  • I thought the shark christ had finally come.

  • old news (Score:2, Funny)

    by hackstraw ( 262471 )
    "The Roman Catholic Bible has an article about a team of prophets that have foreseen that a female human will reproduce without having sex, the first time that prophets have found the unusual capacity in such an ancient vertebrate species. Their report concludes that some humans can reproduce asexually through the process known as Immaculate Conception [wikipedia.org] (the growth and development of an embryo or seed without fertilization by a male)."
  • Unless modern sharks can reproduce with the earliest sharks, I don't think they'd be classified as the same species. I think you mean that the Selachimorpha superorder is ancient.

  • "And who can tell me" (Score:4, Funny)

    by TheDarkener ( 198348 ) on Wednesday May 23, 2007 @11:14AM (#19238781) Homepage
    Teacher: "...And who can tell me the first person to suggest the idea of reproduction without sex?"

    Ferris: "Uhm...Your wife?"

    Bueller? Bueller?
  • yet another reason to stop keeping conscious creatures locked up for the viewing pleasure of curious, callous humans

  • It is not as bad as I thought (Score:3, Funny)

    by Alain Williams ( 2972 ) <addw@phcomp.co.uk> on Wednesday May 23, 2007 @11:49AM (#19239695) Homepage
    After I read the article I realised that they meant the marine predator; from the headline I thought that they meant lawyers!
  • ... the shark offspring bore a striking resemblance to Vern, the tank cleaner.
  • No wonder the male sharks are all pissed off.
  • THIS [antwon.com] will be on the backs of submarines soon enough.
  • ... the King of the Jaws?

Slashdot Top Deals

"Everything should be made as simple as possible, but not simpler." -- Albert Einstein

Close