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Butterfly Unlocks Evolution Secret 1130

Posted by Zonk
from the gotta-love-them-butterflies dept.
Anonymous Coward writes "The BBC has an article about a dramatic discovery in the quest for understanding evolution. From the article: 'Why one species branches into two is a question that has haunted evolutionary biologists since Darwin. Given our planet's rich biodiversity, "speciation" clearly happens regularly, but scientists cannot quite pinpoint the driving forces behind it. Now, researchers studying a family of butterflies think they have witnessed a subtle process, which could be forcing a wedge between newly formed species.'"
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Butterfly Unlocks Evolution Secret

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  • by Anonymous Coward on Sunday July 24, 2005 @06:38PM (#13152403)

    And in a week or two, this submission will evolve only slightly and will reappear, slightly reworded, as another species of submission! Ain't evolution great.

    • by Breakfast Pants (323698) on Sunday July 24, 2005 @06:56PM (#13152519) Journal
      No, but God might decide that is deserves a repost so that some more people can learn about evolution and go to hell.
  • Wasn't this obvious? (Score:5, Interesting)

    by nokilli (759129) on Sunday July 24, 2005 @06:39PM (#13152413)
    Mutations occur, and when they occur in parallel for members of the same species, and those mutations survive into succeeding generations, you achieve speciation. End of story. What am I missing?

    Now, if you want to talk about butterflies and evolution, then answer for me how it is that butterflies could have evolved in the first place. You're talking about a two-stage organism here, one stage does nothing but eat, the other stage does nothing but procreate. Which came first?

    If it was the caterpillar, how is it that it suddenly figures out how to create a cocoon, lay dormant for a winter, then emerge as a completely different creature? They obviously had the means for procreation on their own, so why bother becoming a butterfly?

    If it was the butterfly, why even bother with the caterpillar stage? If you can already fly around and stuff, why bother crawling?

    People cite all these other examples trying to bring down evolution, and to me they never succeed, it's obvious to me for instance how eyes evolved. But caterpillars turning into butterflies still boggles my mind.
    --
    Why didn't you know? [tinyurl.com]
    • by Got Laid, Can't Code (897495) on Sunday July 24, 2005 @06:45PM (#13152456)
      No, it's non-obvious. You missed the point--the cohabiting species have special marks which allow them to choose to mate only with their own species instead of interbreeding. It isn't chance, it's choice.

      As for the caterpillar/butterfly thing, it is mysterious, but I'd like to point out that some of the simplest animals on earth go through life stages. Jellyfish, for example, hydrae, and many other invertebrates go through various stages of life. Amphibians do this as well.

      As far as I can tell, the reason behind it is a reproductive strategy. The butterfly, and other insects, has hundreds of offspring, only a few of which will survive to adulthood and then have hundreds more offspring.

      Humans do not go through such dramatic stages as a butterfly, but a butterfly might be amazed to find out that humans survive for 13 years before reaching reproductive age!

    • by schtum (166052) on Sunday July 24, 2005 @06:53PM (#13152505)
      IANAEB (Evolutionary Biologist), so I'm just going by the article here, but it seems like the process itself was obvious (or at least pre-supposed) as you suggest, it's the chance to witness it in nature that's exciting here.

      I can't really answer your butterfly question, but I can point out that every insect has multiple stages of life. Flies start out as maggots, ... that's all i got. IANAEntomologyst either.

      While we're asking the tough questions, it seems like the one big gun the Divine Design people have left is in the differing number of genes between species. If all offspring have the same number of genes as their parents, and all species on earth are evolved from one original life form, shouldn't all creatures have the same number of genes? Are there any theories out there regarding how genes are added or subtracted over time?
      • by iamplupp (728943) on Sunday July 24, 2005 @07:05PM (#13152566) Homepage
        "If all offspring have the same number of genes as their parents, and all species on earth are evolved from one original life form, shouldn't all creatures have the same number of genes? Are there any theories out there regarding how genes are added or subtracted over time?"

        There are many mechanisms for adding, changing, and subtracting genetical information (translocations, mutations, deletations, insertions, non-disjunction etc etc. In the vast majority of cases the results are death for the offspring but in a rare few cases it results in viable and even rarer, a better adapted offspring. For an everyday example: People with Downs Syndrome have either an extra 23rd chromosome or a robertsonian translocation with pretty much the same added genetic material as a result. That means they have roughly 2 percent more genes than other people...
        • by Orozco (639667) on Sunday July 24, 2005 @09:51PM (#13153390)
          I believe you mean the 21st chromosome. The 23rd chromosome is the sex chromosome, and the effects of having an extra one depend on the resulting genotype. The possibilities are XYY, XXY, and XXX (gasp!). If I remember correctly, the XYY variety typically dies very young (it may not survive to birth.) The XXY flavor results in Klinefelter's syndrome, which causes sterility (the person is male, but during puberty the testicles do not fully develop) and slight deficits in speech and motor learning (which can be overcome by playing sports and having good teachers). I can't remember what happens with the XXX variety. So there's more than you ever wanted to know about Trisomy-23. To make this reply relevant to the post, trisomy typically happens through nondisjunction, in which two copies of a chromosome do not separate from each other during meiosis (this happens in the sex cells of on of the parents.)
      • by Tau Zero (75868) on Sunday July 24, 2005 @09:40PM (#13153334) Journal
        If
        1. all offspring have the same number of genes as their parents, and
        2. all species on earth are evolved from one original life form,
        shouldn't all creatures have the same number of genes?
        Premise #1 is false. One common way for plants to speciate is to double their chromosome count (not individual genes, entire sets of chromosomes). Humans are diploid (two sets of chromosomes, one from each parent); some plants are quadruploid or hexaploid (SIX sets of chromosomes, three from each parent).
        Are there any theories out there regarding how genes are added or subtracted over time?
        Then you have crossover mutations. When chromosomes are duplicated in mitosis, the two new DNA strands are wound up with the originals and have to be untangled. This is done by enzymes which snip one strand pair, allow the other to pass through the gap and repair the bond afterwards. Sometimes this process isn't perfect, and a DNA strand pair gets part of the other's chromosome or loses a chunk. Entire genes can be lost or duplicated this way. Duplicated genes allow one of the pair to mutate and take up new functions, and it turns out that a whole lot of biological "inventions" come from genes which appear to have come from other, older genes.

        Then you've got tandem sequence repeats... which is a whole 'nother story, but they are very susceptible to DNA copying errors and you can evolve e.g. a very different curve of a dog's snout in a century by selecting for different lengths of tandem repeats.

        Yes, all this stuff is on the web. Everything you need to completely and authoritatively refute every argument made by creationists (the "intelligent design" brand or the traditional) is on the web.

        (Okay, who's the Slashcode nitwit whose filter cancels the <i> tag when a list is started?)

    • Non-Mutation Split (Score:5, Interesting)

      by DrWho520 (655973) on Sunday July 24, 2005 @07:17PM (#13152634) Journal
      In higher order animals, such as Orcas, behavioral differences can bring about the separation into two species. There are two distinct groups of Orcas, those which hunt fish and those which hunt seals. These two behaviors are fairly different, as fish hunting Orcas herd schools of fish to make consuming them easier. Seal hunting orcas are know to "dive" several feet onto ice flows to catch seals. They also thrash seals around in the water to subdue them. These two groups do not mix as their learned behaviors and sub-environs are different. It is easy to imagine that these two groups are slowly diverging, as they engage in different diets, breed within their own groups and engage in different physical activities.

      Of course, I am a physicist and a mathematician. All of my bio-knowledge comes from The Discovery Channel.
      • by Savage-Rabbit (308260) on Sunday July 24, 2005 @08:12PM (#13152898)
        It is easy to imagine that these two groups are slowly diverging, as they engage in different diets, breed within their own groups and engage in different physical activities.

        That might actually apply to humans as well. I mean take Conservatives and Liberals. They engage in different physiclal activities and (mostly) breed within their own groups. So will the two eventually evolve into seperate species, Homo Conservativis and Homo Liberalis? Probably, however, due to the high population denisty among humans they will also be unable to escape having to interact with each other. So the two resultant species and their behavioral patterns will influence each others evolution won't they? I mean you would for example expect the Homo Conservativis to evolve sophisticated selective hearing in order to avoid hearing anything that Homo Liberals might say that contradicts with their religious ideas while the Homo Liberals will grow thick Neanderthal like skulls due to Homo Conservatives incessantly thumping theim on the head with a Bible.
      • by Boronx (228853) <evonreis@mohr-en g i n e e r i n g . com> on Sunday July 24, 2005 @08:14PM (#13152905) Homepage Journal
        Another difference between the two groups is that fish hunting orcas are always chattering amongst themselves, but mammal hunting orcas are very quiet, because their pray is smart enough or has ears enough to pick up on the yammering.
    • by mblase (200735)
      You're talking about a two-stage organism here, one stage does nothing but eat, the other stage does nothing but procreate

      Think of the chrysalis as puberty for the caterpillar. I'm actually envious--I'm sure many of us would have just as soon lived out our teenage years laying in bed, sleeping, twenty-four hours a day until we were ready to emerge into the wonderful world of twenty-year-old, sexually mature adults instead of being pressured to explore the opposite sex while at the same time dealing with v
    • by blonde rser (253047) on Sunday July 24, 2005 @07:43PM (#13152745) Homepage
      Mutations occur, and when they occur in parallel for members of the same species, and those mutations survive into succeeding generations, you achieve speciation. End of story. What am I missing?

      It seems to me that you are just completely glossing over the non-obvious part. The part where the members with the mutations stop reproducing with the rest of the non-mutated species for long enough that the two branches are unable to breed with each other at all after a certain point. Why should a mutation stop breeding with members who haven't mutated. Or if it is built in to the behaviour that the species will not breed with mutants then how do the mutants not have this behaviour so that they may breed with each other. It is this stage that is being observed in the article.

      Your butterfly question seems cute but quaint. Really, I think if it seems obvious to you how eyes evolved then I doubt you fully understand the problem. There are just too many very bright people out there who are interested in this as a problem (I'm talking about people who believe in evolution but can't explain all the mechanics) for it to be trivial.
    • by zambuka (301663)
      Here is what I think about butterfly (and any creature that goes through a laval/pupation stage)

      By being born with little more than the ability to eat and move to the next meal they save the parent a huge amount of energy. Usually a parent creature has to drop a lot of their energy and food into incubating or laying an egg that will feed the young until they reach a fully matured stage.

      With butterflies, flies and most other insects it becomes more efficient to lay an egg with only enough energy to create
  • by ejito (700826) on Sunday July 24, 2005 @06:40PM (#13152421)
    are racist...
  • Yes!!! (Score:4, Insightful)

    by recoiledsnake (879048) on Sunday July 24, 2005 @06:44PM (#13152450)
    This is why I love science,new and exciting discoveries every day and answers to so many interesting unanswered questions. A very welcome change to the religious people's "God did it! now go pray".

    I am sure that given enough time, scientists can plug holes in the theory of evolution and answer questions that critics throw at it like. Remember, a theory can always be changed and disproved by evidence unlike intelligent design which can't be disproved(and no one seems to have proved it either).

    And before someone starts an intelligent design rant, please remember, unprovable assumptions like 'there's a naturally occuring ipod on the dark side of the moon, since you can't disprove it, it exists' have no place in science at all. Also remember, science is self criticizing and self correcting, read up on the criticism on string theory if you have any doubts.

    • Re:Yes!!! (Score:5, Insightful)

      by gardyloo (512791) on Sunday July 24, 2005 @06:46PM (#13152462)
      I am sure that given enough time, scientists can plug holes in the theory of evolution and answer questions that critics throw at it [...]

      I find your faith refreshing...
    • Re:Yes!!! (Score:3, Insightful)

      by BillyBlaze (746775)
      I can disprove it: There is no dark side of the moon, thus, there couldn't be an iPod there. :-)

      Otherwise, point taken.

    • Re:Yes!!! (Score:5, Insightful)

      by The_Wilschon (782534) on Sunday July 24, 2005 @08:02PM (#13152851) Homepage
      A very welcome change to the religious people's "God did it! now go pray".

      Please, don't lump all "religious people" together under the umbrella of fundamentalists. I know that there are a very large number of people out there, including myself, who find no problem with saying "God did it! I'd like to find out how!" And discovering that evolution (which is really a fascinating process, and deserving of study) is our current best guess. I find no contradiction between the idea that God created the world and the idea that evolution happened and happens. And I know that there are a lot of people out there who agree with me. If I had to guess, I would say that the majority of "religious people" haven't really thought about it, but among those who have, the group who claims incompatibility between creation and evolution is a vocal minority.

      You are correct that undisprovable statements are not science. However, this does not necessarily preclude them being true. I heartily agree that the fact they are undisprovable does not make them true, but neither does it prevent them from being true. Not that you claimed it did; I'm just throwing that out there in addition.
      • Re:Yes!!! (Score:4, Insightful)

        by antiMStroll (664213) on Sunday July 24, 2005 @11:31PM (#13153771)
        "A very welcome change to the religious people's "God did it! now go pray"."

        Please, don't lump all "religious people" together under the umbrella of fundamentalists.

        An unfortunate shorthand. Not all religious people are fundamentalists but all fundamentalists are acting in the name of religion. We need louder moderates.

  • so... (Score:5, Funny)

    by passion (84900) on Sunday July 24, 2005 @06:46PM (#13152461)
    they've decided to fork?
  • by truckaxle (883149) on Sunday July 24, 2005 @06:46PM (#13152464) Homepage
    FTA

    The other mechanism that can theoretically divide a species is "reproductive isolation". This occurs when organisms are not separated physically, but "choose" not to breed with each other thereby causing genetic isolation, which amounts to the same thing.

    Does this mean that geeks are soon to speciate and then ultimate fail as the male/female ratio is horrendously out of wack?
    • by CptPicard (680154) on Sunday July 24, 2005 @07:41PM (#13152740)
      No, it means that the geek species will survive the skewed gender ratio through adopting a polygamist model where one geek girl has a harem of 50 geek boys, using them as her semen producers and sex toys as she pleases while she is not solving differential equations or writing code.

      I, for one, welcome our new geek dominatrix overladies!
  • And racism? (Score:5, Interesting)

    by mcrbids (148650) on Sunday July 24, 2005 @07:10PM (#13152598) Journal
    I wonder if this has any impact on the view of racism?

    Racism is a *very* touchy subject, and I may get flamed just for bringing it up, but doesn't this sound like butterfly racism? If this were, in fact, a provable, natural, biological mechanism, then, wouldn't we, as biological organisms, be falling prety to much the same effect? Isn't racism a social form of speciation?

    What impact would this have on the ACLU? Hiring quotas? The civil rights movement in general?

    I'm not suggesting that racism is good. But, might these be related?
    • Re:And racism? (Score:3, Insightful)

      by potpie (706881)
      >>What impact would this have on the ACLU? Hiring quotas? The civil rights movement in general?

      Seems like the concept of Social Darwinism [ http://en.wikipedia.org/wiki/Social_darwinism [wikipedia.org] ]. Pop philosophers tried to aply the findings of Darwin to modern social stratification as a sort of apology for the rich.

      But since when have humans played by the rules of nature like that? We don't eat our young just because other species do. We don't appoint a single woman as the breeder for a group like ants
    • Re:And racism? (Score:3, Interesting)

      by Randseed (132501)
      Of course it is. A human "race" is simply a group of people who, for whatever reason (ideological, religious, geographical, etc.) mated within their own group. This allows mutations which occur within that group to stay there, rather than get folded over the entire genome. Continue this for long enough, and some of those mutations will result in situations where members of different races can't reproduce with each other.

      As an ass-backward example, consider sickle cell anemia. The sickle cell trait (Ss), w

    • Re:And racism? (Score:3, Insightful)

      by JaredOfEuropa (526365)

      Racism is a *very* touchy subject, and I may get flamed just for bringing it up, but doesn't this sound like butterfly racism? If this were, in fact, a provable, natural, biological mechanism, then, wouldn't we, as biological organisms, be falling prety to much the same effect? Isn't racism a social form of speciation?

      Yes and no. The problem lies in the definition of racism. Many people have taken it so far as to say that all people are equal... obvious stuff as skin color aside, and referring to skin

    • Re:And racism? (Score:4, Insightful)

      by PengoNet (40368) on Sunday July 24, 2005 @08:21PM (#13152943) Homepage
      Firstly, sexuality and racism are different subjects. These butterflies are more sexually attracted to certain markings or patterns, which indicate the partner is of the same species. They aren't hiring other butterflies for jobs, nor pulling them up for minor driving offenses.

      There is no racism in finding yourself sexually attracted to certain racial characteristics such as skin colour.

      You ask, "Isn't racism a social form of speciation". No. Racism is racism. There are many reasons why this racist segregration would not lead to speciation, even if it were not a morally repulsive proposition:

      1) No reinforcement, i.e. segregration is not selected for. As far as evolution of humans is concerned, offspring of people of different races are not "weedy and less likely to thrive" as in the butterfly example, but quite the contrary. So from a biological point of view, we should not expect to find ourselves splitting into seperate species as there is no "reinforcement" (as mentioned in the article), but instead the opposite. Of course humans are still very much the same species, and are currently showing no signs of speciation, and comparing human races to butterfly species is stretching it.

      2) Very little gene flow is needed to prevent speciation. One "mixed marriage" out of one hundred is plenty to keep genes flowing between subgroups within a species. This coupled with the above (the offspring being strong and healthy) makes it nearly inevitiable

      3) Most people's concept of race is misguided. For example: Humans were originally black. So it's not surprising that there are people within all (eight?) major branches of our collective tree with black skin. Human movement and migration has lead to us all being much more related than you'd probably guess.

      4) Timeframe: butterflies may have several generations each year. Even so, the researchers in the article don't appear to even witness speciation in action, but takes a snapshot and explains how it has occured. Speciation takes a long time. It's likely to take 100,000 years for humans to start showing signs of speciation, that is, if there was an evolutionary push towards it. Justifying racism on the basis that your great great great great great [25,000 "great"s removed to prevent this comment from violating the "postercomment" compression filter] great great great great great great great great great grandson or daughter may belong to a different species as the person next to you, is pretty fucking stupid.
    • Re:And racism? (Score:5, Insightful)

      by Thaelon (250687) on Sunday July 24, 2005 @09:33PM (#13153310)
      I think you almost hit the mark. I can only speak for myself (and perhaps throw myself to the wolves in the process) but I find I'm not particularly attracted to females that are drastically different from Anglo-Saxon. I can look at a beautiful say.....black woman and see that she is indeed beautiful. But I'm not usually attracted to her. It's like looking at a fine work of art or other thing of beauty that doesn't inspire primal urges. I can appreciate her beauty without my baser instincts firing to say "ATTEMPT TO MATE!"

      Don't get me wrong, I'm not racist. In fact in moving to VA I find the higher percentage of non-white folks refreshing and believe that interracial breeding will generally make better humans.

      Just like "pure bred" dogs typically have horribly high tendencies to have breed-specific problems whereas mutts whose component breeds aren't even discernible live much longer and healthier. This coming from a guy who grew up in areas with lots of "pure bred" humans. *shudder*

      However, in closing I wouldn't say racism is speciation. Racism is irrational, ignorant, stupid dislike of other races. Speciation is more what I'm talking about. How some people aren't attracted to other races may cause it among humans.
    • Re:And racism? (Score:3, Insightful)

      by king-manic (409855)
      I wonder if this has any impact on the view of racism?

      Racism is a *very* touchy subject, and I may get flamed just for bringing it up, but doesn't this sound like butterfly racism? If this were, in fact, a provable, natural, biological mechanism, then, wouldn't we, as biological organisms, be falling prety to much the same effect? Isn't racism a social form of speciation?

      What impact would this have on the ACLU? Hiring quotas? The civil rights movement in general?

      I'm not suggesting that racism is good. Bu
  • Damn (Score:4, Funny)

    by teslatug (543527) on Sunday July 24, 2005 @07:26PM (#13152673)
    /me looks at self for stripes that keep the females away
  • by Dark Paladin (116525) * <jhummel@NosPam.johnhummel.net> on Sunday July 24, 2005 @07:26PM (#13152674) Homepage
    Don't tell the Kansas schoolboard - they have enough on their hands trying to deny all of the other evidence for evolution to have to handle another one.
  • Misleading Article (Score:5, Informative)

    by Geancanach (652302) on Sunday July 24, 2005 @07:41PM (#13152738)
    This article from the BBC is misleading. I tracked down the original article in Nature.

    The researchers didn't actually unlock any major secrets. It is no secret that two species who would not produce viable offspring together will try to avoid mating with each other. There are various mechanisms for doing that - having different wing colors so that species can distinguish their optimal mating partners is one method. If the two species are geographically separated, there is no need to develop other methods of separation, and thus their wing colors can look similar. There is nothing new about this.

    Also, the BBC article never explains that the speciation of these butterflies occurred while they were geographically separated (this is called allopatric speciation, and the Nature article specifically states that the butterflies evolved this way). The species only developed different wing markings when they came back into contact with each other. This makes a lot of sense - they were now genetically very different, and offspring between members of different species would not be successful, so they needed ways of telling each other apart.

    It's a nice finding, but certainly not the unlocking of a major secret.
  • by JordanH (75307) on Sunday July 24, 2005 @07:42PM (#13152744) Homepage Journal
    I've been wondering at something for quite some time that might be related to this discovery.

    Why is it that animals that are "domesticated" or mostly live in close cooperation with human societies, like pigeons, develop highly variegated markings?

    Think about it, cats, dogs, chickens, pigeons, cows, all of these exhibit wild variation in marking and coloration when they live with humans. Even humans themselves seem to have more variability when compared to other primates.

    Perhaps human ecosystems and breeding have removed other pressures so the marking variations are more likely to express? I dunno. Just an observation. Any geneticists or evolutionary theorist out there have any ideas about this?

    • by Oscar_Wilde (170568) on Sunday July 24, 2005 @08:34PM (#13153013) Homepage
      Think about it, cats, dogs, chickens, pigeons, cows, all of these exhibit wild variation in marking and coloration when they live with humans. Even humans themselves seem to have more variability when compared to other primates.

      It's just because of selective breeding. If you let different dog breeds mate then after a few generations then they tend towards the "basic dog" type.

      For a more detailed and accurate description take a look at the Wikipedia article on mixed-breed dogs [wikipedia.org].
  • by soapdog (773638) on Sunday July 24, 2005 @07:50PM (#13152786) Homepage
    Let me explain evolution... theres specie Geek, the Vi x Emacs force a species split up. Then we've got Vi Geek and Emacs Geek, after couple years they can't even talk to each other anymore, the Vi Geek always trying some cryptic commands and the Emacs Geek mutating more fingers to type even bigger key-chords... it's the same with butterflies I think... RGB Butterfly, CMYK Butterfly...
  • by beaverbrother (586749) on Sunday July 24, 2005 @08:39PM (#13153046)
    Damn smart butterfly
  • Mississippi Burning (Score:4, Interesting)

    by nathanh (1214) on Sunday July 24, 2005 @09:42PM (#13153339) Homepage
    The team, from Harvard University, US, discovered that closely related species living in the same geographical space displayed unusually distinct wing markings.

    These wing colours apparently evolved as a sort of "team strip", allowing butterflies to easily identify the species of a potential mate.

    Hrm. I watched Mississippi Burning last night and one thing that struck me dumbfounded was the irrational hatred towards blacks shown by the white protagonists in the film.

    That article makes me wonder whether racial hatred is in part inspired by this "team strip" concept in the butterflies. In other words, the white protagonists are acting on their animal instincts to use "reinforcement" (as the article calls it) to encourage speciation.

    I'm aware there are countless other factors involved in racial bigotry, including the fact that the white supremacists are a bunch of pathetic losers, but I'm always interested in scientific rationales for seemingly irrational behaviour.

  • Newsbreak (Score:4, Funny)

    by warkda rrior (23694) on Sunday July 24, 2005 @11:29PM (#13153766) Homepage
    In unrelated news: Tennessee bans butteflies.

One possible reason that things aren't going according to plan is that there never was a plan in the first place.

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