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Science

Organism Survives 100 Million Years Without Sex 343

Posted by samzenpus
from the they-must-play-dungeons-and-dragons-too dept.
zyl0x writes "The Times has an interesting article online on the discovery of a 100-million-year-old micro-organism which has survived its entire lifespan without sex." From the article "A tiny creature that has not had sex for 100 million years has overturned the theory that animals need to mate to create variety. Analysis of the jaw shapes of bdelloid rotifers, combined with genetic data, revealed that the animals have diversified under pressure of natural selection. Researchers say that their study "refutes the idea that sex is necessary for diversification into evolutionary species".
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Organism Survives 100 Million Years Without Sex

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  • by Veroxii (51114) on Wednesday March 21, 2007 @11:57PM (#18439503)
    This happens on Slashdot all the time.

    Move along...
  • by Harmonious Botch (921977) * on Wednesday March 21, 2007 @11:58PM (#18439507) Homepage Journal
    It should be right at home here.
    • by yintercept (517362) on Thursday March 22, 2007 @12:29AM (#18439713) Homepage Journal

      "It should be right at home here."
      The article says that all of the bdelloid rotifers are females.

      Your point is refuted.
  • Slashdotters (Score:2, Redundant)

    by metlin (258108) *
    Now you know how Slashdotters will look after a hundred million years!

    On a serious note, no sex, no evolution -- doesn't look like this organism has changed all that much in hundred million years.

    Support evolution: get laid now!
    • Re:Slashdotters (Score:5, Informative)

      by niloroth (462586) on Thursday March 22, 2007 @12:07AM (#18439579) Homepage
      actually, the main point of the story is that it has changed, has evolved. There is no reason to believe that evolution stops if there is no sex, natural selection is quite happy to use mutation as a tool for evolution, just as it does sex. The difference being that sex tends to speed the process up with different combinations of genes with most offspring.
      • > actually, the main point of the story is that it has changed, has evolved. There is no reason to believe that evolution stops if there is no sex, natural selection is quite happy to use mutation as a tool for evolution, just as it does sex.

        Which is hardly news, since we've long known that the whole family tree stems from asexual organisms. If they didn't evolve, we wouldn't be here to comment on it.
      • by Rimbo (139781) <rimbosity AT sbcglobal DOT net> on Thursday March 22, 2007 @01:54AM (#18440083) Homepage Journal
        Well, clearly sex isn't the only way to achieve diversification.

        It's just more fun that way.
      • Re: (Score:3, Interesting)

        by Cadallin (863437)
        I understand the point of the story quite well, which is quite different from the title BTYW, but how is this a new discovery? Bacteria have been getting along without sex (mostly, see plasmid transfer for details) for a good 4+ billion years. Is it because this is a multicellular animal? I really don't see what the fuss would be.
    • Sex and Diversity (Score:5, Informative)

      by camperdave (969942) on Thursday March 22, 2007 @06:35AM (#18441253) Journal
      On a serious note, no sex, no evolution

      The purpose of sexual reproduction (mitosis) is to blend genetic traits, and thus diversify the species. However, I can think of a number of ways that genes can be modified without mitosis:
      • Mutation. A stray cosmic ray, or bit of radiation hitting the DNA at just the right spot.
      • Virus. A virus could inject a change into the DNA strand of the organism.
      • Hijacking. Perhaps the organism can take DNA strands from its food, or from another organism and combine them with its own.
      • Pre-encoding. The DNA of the organism may actually encode enough information to build several versions of the creature, and which version gets built is random, or determined by the environment, or is cyclical (the way that certain characteristics skip generations).
      ... or perhaps the creatures are slipping off for a "quickie" while the scientists aren't looking.
      • Re:Sex and Diversity (Score:4, Interesting)

        by Rei (128717) on Thursday March 22, 2007 @10:48AM (#18444185) Homepage
        For God's sake, I had to get through 3/4 of the page before I finally found a post that was on-topic. :P

        One should note that there are higher organisms that are parthenogenic as well -- for example, some species of whiptail lizards. Interestingly enough, they often still have to "mate" (even though they're all females) in order to induce ovulation and thus pregnancy. As for the dominant theories considering them:

        "One suggestion is that the parthenogenic species are newcomers on the scene, having existed for only hundreds of years, rather than the hundreds of thousands or millions of years of most reptile species (Wright, 1993). It is noted that the geographic ranges of parthenogenic whiptails is significantly less than that of bisexual species (Schall, 1993). Perhaps the parthenogens haven't been around long enough to displace their bisexual competitors.

        Another suggestion is that the parthenogenic species are opportunistic 'weeds,' adaptable enough to quickly exploit new or disturbed ecosystems. In support of this hypothesis is the fact that the reproductive capacity per generation for an all female population is (nominally) double that of a population comprising half males. The studies reported in the present work were not of long enough duration to convincingly confirm or refute this notion. The issue remains unresolved. "

        (from http://home.pcisys.net/~dlblanc/articles/whiptail. php [pcisys.net])
        I don't know how long it's been since they diverged, though. Sexual selection and the horizontal genetic drift it allows is an "aid" to evolution, but it's not necessary.
  • Scientists have named this new species Republicanus Typicalus.
    • http://abcnews.go.com/Primetime/News/story?id=1802 91 [go.com]

      Primetime Live Poll: More Republicans Satisfied With Sex Lives Than Democrats

      New 'Primetime Live' Sex Survey Reveals That More Republicans (56 Percent) Are Very Satisfied With Their Sex Lives Than Democrats (47 Percent)

  • by Anonymous Coward on Thursday March 22, 2007 @12:00AM (#18439523)
    ...it's married.
  • by Swave An deBwoner (907414) on Thursday March 22, 2007 @12:00AM (#18439527)
    It is gratifying to see an article about me, but why did they add in the irrelevant stuff about bdelloid rotifers?
  • by madhatter256 (443326) on Thursday March 22, 2007 @12:02AM (#18439539)
    Is that what you would name this micro-organism?
  • by littlewink (996298) on Thursday March 22, 2007 @12:02AM (#18439543)
    While 100 million years seems like a long time, perhaps it is married and has a wife. That would explain everything.
    • by TubeSteak (669689)

      While 100 million years seems like a long time, perhaps it is married and has a wife. That would explain everything.
      I'm not sure how deep your humor was meant to go,
      but the organism in question is female & reproduces asexually.
      So if anything, it's a woman married to herself.

      Maybe there really is something to those stereotypes...
  • by LynnwoodRooster (966895) on Thursday March 22, 2007 @12:04AM (#18439547) Journal
    I see they finally studied the mating habits of the married American male...
  • by bky1701 (979071) on Thursday March 22, 2007 @12:05AM (#18439559) Homepage
    ...who read this as a single organism living for 100 million years without having sex? First part said "wow", second part made me feel like I had been out-geeked...
  • by Telephone Sanitizer (989116) on Thursday March 22, 2007 @12:06AM (#18439561)
    From the look of those mandibles, it's the foreplay that kills 'em.
  • ...Huh? (Score:4, Interesting)

    by Razzendacuben (985660) on Thursday March 22, 2007 @12:07AM (#18439581)
    Who ever said sex was necessary for diversity? It just speeds it up - what's the big deal about this discovery? There are a crazy number of organisms that don't have sex and have changed a hell of a lot over time.
    • Re: (Score:3, Informative)

      by Angostura (703910)
      Precisely. Any asexual reproductive process, coupled with random mutation and selection will lead to genetic diversity in a population. It just means that the rate of change is dependent on random mutation alone, rather than having the added boost of sexual mixing. Not a non-story, but not an earth-shattering one.

    • Re: (Score:3, Interesting)

      by kestasjk (933987) *
      Finally, a post that isn't "100 million years? Sounds like a /. geek"

      One other thing that makes this news story a little strange is 'Researchers say that their study "refutes the idea that sex is necessary for diversification into evolutionary species".'. It seems like a strange thing to say, since the definition of a species is a group of animals that interbreed and have fertile offspring in the wild.

      How do you even clearly define a species if it doesn't have sex?
      • Re: (Score:3, Insightful)

        by radtea (464814)
        How do you even clearly define a species if it doesn't have sex?

        This is an excellent question, and strongly suggests that if we view evolution from a mathematical perspective that there are strong attractors in the environment that maintain species boundaries. Otherwise, we would expect a lot more diversity amongst asexual species, as every individual would spawn a whole bunch of imperfect copies that would all do about equally well.

        It may be that ecological competition is the key to maintaining the morpho
  • Gene Transfer? (Score:4, Interesting)

    by logicnazi (169418) <logicnazi@gREDHATmail.com minus distro> on Thursday March 22, 2007 @12:09AM (#18439589) Homepage
    It was discovered wearing a ratty linux t-shirt.

    Sorry, I couldn't resist. Seriously however the article was very unclear. What is it that asexual organisms aren't able to do? Surely it isn't that they can't diversify into different species. After all every organism on earth is descended from the same intial life form and some organisms are still asexual hence establishing that the initial lifeform diversified into some progenitor sexual organism as well as branches that remained asexual.

    My best guess as to the claim made in the article is that multi-celluar organisms require sexual reproduction to select for organism wide traits. Not sure why it would be true (maybe different cells don't have enough incentive to look out for the whole organism) but that's my best guess.

    Anyway saying that the organism doesn't have sex isn't very clear. Many bacteria exchange genetic material without having sex. Such a system might let this creature gain some of the benefits of sexual selection.

    Does anyone understand what this article is actually trying to say? I know it's a funny title but some info would be nice too.
  • by Hal_Porter (817932) on Thursday March 22, 2007 @12:09AM (#18439601)
    Front page stories

    * Dungeons & Dragons and IT
    * Organism Survives 100 Million Years Without Sex
    * Gifted Children Find Heavy Metal Comforting

    Did anyone see suck's parody of slashdot?

    http://www.suck.com/daily/99/12/13/daily.html [suck.com]

    Doesn't seem so funny now, does it?
  • Blisters (Score:4, Funny)

    by Himring (646324) on Thursday March 22, 2007 @12:12AM (#18439615) Homepage Journal
    Of course, it had one hellashish case of masterbation blisters....

  • by Fastball (91927) on Thursday March 22, 2007 @12:12AM (#18439617) Journal
    Did anyone else read that headline as "Orgasm Survives 100 Million Years Without Sex?" That'd be a pretty impressive feat!
  • ...scientists *don't* say "that sex is necessary for diversification into evolutionary species".

    Sex *does* lead to diversity *within* a species, which can be good for keeping ahead of parasites and diseases, and all the genetic duplication can help accelerate diversification. But sexual reproduction, in the absence of other sources of genetic variation, does not lead to speciation.

    • by Rakishi (759894)
      Except that the mechanism by which we pass genes onto our offspring leads to mutation (crossovers can happen in the middle of genes). Even if we only had crossovers that didn't alter genes it is still possible to have speciation as genes don't function alone but in groups.

      Now without crossovers at all (or other mutations), where you literally get a single chromosome from each parent you'd likely get less diversity with time. Sooner or later a small group of chromosomes will come out ahead and all the previo
  • so what? (Score:4, Informative)

    by eobanb (823187) on Thursday March 22, 2007 @12:37AM (#18439753) Homepage
    I actually don't see what the big f**king deal is. If you understand evolution, you probably know that natural selection does not depend on sexual reproduction. It just depends on reproduction, period. It's not as if this single, individual organism has lived 100 million years; its asexual offspring have lived that long, and any time in asexual reproduction, mutations can also occur. I repeat, IT IS NOT SPECIFIC TO SEXUAL REPRODUCTION.

    I would fathom that mutation might happen more often with sexual reproduction, and thus asexual reproduction could slow the pace of evolution, but again, that's not to say it doesn't happen. Because it very surely does, as we know from the mutation of all those single-celled asexual organisms we know about. Like every disease out there. It is absolutely nonsense to claim otherwise. Bacteria multiply asexually. Protists do too. This is why diseases resist new drugs. Countless species of plants reproduce asexually. Myriad species of all these kingdoms have survived for 100 million years.

    The headline might as well be, 'there has been life on Earth a long time.'
    • Re: (Score:3, Informative)

      by tijnbraun (226978)
      Well... some biologist do have a problem with the Bdelloid rotifers.
      John Maynard Smith [wikipedia.org], not a small thinker among biologist, called these creatures "An Evolutionary Scandal" [harvardmagazine.com].
      It is true that bacteria produce asexuall, but they still exchange genetic material using conjugation [wikipedia.org].
    • Re: (Score:2, Redundant)

      by suv4x4 (956391)
      I would fathom that mutation might happen more often with sexual reproduction, and thus asexual reproduction could slow the pace of evolution, but again, that's not to say it doesn't happen. Because it very surely does, as we know from the mutation of all those single-celled asexual organisms we know about. Like every disease out there. It is absolutely nonsense to claim otherwise. Bacteria multiply asexually. Protists do too. This is why diseases resist new drugs. Countless species of plants reproduce asex
    • Re: (Score:3, Funny)

      by shadowcabbit (466253) *

      I actually don't see what the big f**king deal is.


      Actually, you've about nailed it. No fucking is apparently a big deal.
  • by CCW (125740) on Thursday March 22, 2007 @12:41AM (#18439777)
    This discovery doesn't refute anything. Sex has never been a requirement for diversification. That's just silly. Single celled organisms reproduce clonally, and there are millions of species. (they do utilize gene transfer, but that isn't the same as sexual reproduction)

    Inheritable differences and selection are sufficient. Mutation is a fine source of inheritable differences. Sex allows greater rates of diversity and retention in the population of undesirable traits that are not dominant for longer, allowing them time to mutate into something useful or show up when environmental factors make them useful. Sexual reproduction is far and away the most common mode in multicellular organisms, probably because it helps the species be resilient to environmental changes. But it isn't required.

    • Re: (Score:3, Informative)

      by Pedrito (94783)
      The parent poster id mostly correct. However, not all single celled organism reproduce "clonally" or, asexually. Some do, some don't, some do both. It's true that more genetic diversity comes by combining the genetic material of two different haploid cells (sperm and ovum), but some diversity as the parent poster pointed out, mutations are a source of diversity. Most mutations are harmful, but when you have a population of, hell, I don't even know what the numbers are for and individual species of rotifers,
  • Trust me (Score:5, Funny)

    by edwardpickman (965122) on Thursday March 22, 2007 @12:50AM (#18439823)
    it just seemed like a 100 million years.
  • Always heard... (Score:3, Informative)

    by edwardpickman (965122) on Thursday March 22, 2007 @12:57AM (#18439849)
    I had always read that sex wasn't nessaccary for diversity but it excellerates the process. It would be more of a story if the microorganism had mirrored the diversity of sex based organisms without the benefit of sex. The mutation rate is higher with sex providing for a more varied gene pool and it allows for those genes to be randomly exchanged.
  • The microscopic animals, less than four times the length of a human sperm

    At first, I thought if I was that small I'd have a hard time finding a mate too. Then it struck me. Who the hell compares the size of anything to sperm. Couldn't they say it was less than 1/10 the width of human hair?
  • by warm sushi (168223) on Thursday March 22, 2007 @01:20AM (#18439931)
    Researchers say that their study "refutes the idea that sex is necessary for diversification into evolutionary species".

    I have never even heard the idea (during a degree in genetics) that sex is necessary for diversification into species. Bacteria do not have sex (although they can share DNA through other means, such as plasmids) and yet that are incrediably diverse and continue to evolve rapidly (e.g. antibiotic resistance). Therefore, if sex were necessary for speciation we would only have one species of bacteria.

    The term "evolutionary species" is also strange. All "species" are by definition "evolutionary", since that is the process by which individual species arise.

  • What's sex?
  • Who's first? (Score:2, Insightful)

    by Gerzel (240421)
    So how long before the Cristian Right tries to use this study as "proof" that evolution is just a hoax and has been "proven wrong" by science. Or do they ever even bother giving actual sources for their claims anymore?
    • Re: (Score:2, Insightful)

      by redGiraffe (189625)
      There's just one snag (well, maybe more:) - they would have to explain how a 100 million year old organism fits into a world of only 6 thousand years old.

      I'm sure logic will not hinder them in finding some lame-ass explanation - news at ten.
  • by Plutonite (999141) on Thursday March 22, 2007 @01:50AM (#18440063)
    welcome our abstinent 100-million year old micro-organic losers *cough* overlords.
  • From Wargames;

    Mr. Liggett: Alright, Lightman. Maybe you can tell us who first suggested the idea of reproduction without sex.

    David Lightman: Um, your wife?
  • by GFree (853379)
    I'd feel concerned for any creature which DID end up having sex after 100 million years.

    Given all that pent-up need, they probably blow with enough force to launch the space shuttle.
  • by malia8888 (646496) on Thursday March 22, 2007 @02:41AM (#18440277)
    Two sister species were found to be living together on the body of a water louse. One of them specialised in living around the louse's legs and the other stayed close to the chest.
    And I thought I had a crappy dorm room.
  • that this will be the longest thread on slashdot. Ever.
  • by mapkinase (958129) on Thursday March 22, 2007 @07:26AM (#18441519) Homepage Journal
    Independently Evolving Species in Asexual Bdelloid Rotifers. [plosjournals.org].

    I always have trouble reading about findings of "two close species". Article claims that they are too different genetically to be one species, too different ecological niches to be one species, yet dispite the differences they find it proving that they are "evolutionary related". If they are too distant then they might be created using non-evolutionary ways (aliens came, looked at the rotifer and decided to make it live in another organ of the lice). If they are similar, then what does prevent us to call asexual organisms one species?

    In sexual organisms there is a clear boundary between species - productive progeny of mating between two organisms. If a couple does not produce productive progeny - male and female belong to different species, if they do - they are from the same species. That is why using asexual organisms to support pseudo-science of evolution is particularly lame: all the arguments are tautologically meaningless reducing themselves to "diversity".

    About that: authors write

    If asexual clades displayed the same pattern of discrete variation as sexual clades, this would challenge traditional view that sex is necessary for diversification into species.
    First of all, that has been traditional view long time ago, but evolutionists have been convinced that sex is not necessary for evolution for quite some time. And you do not have to be a specialist to know that. Look at bacteria.

    Second. How would you know if clades are displaying the same pattern or different pattern or any pattern, if you for sure do not know all the representatives of the clade that ever existed? For example, according to "traditional" view of evolutionists reptiles were much more diversed before 100M years ago than they are now.

    It is essentially comparing diversity of two arbitrarily (which is different from randomly) selected samples. And the difference between "arbitrarily" and "randomly" is that first is biased selection (some species exist no more for all kinds of reasons).

    And this is a beginning of the article.

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