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Science

Did an Exploding Comet Doom Early Americans? 89

New Scientist outlines a new theory on the demise of the Clovis people in the southwest US over 10,000 years ago. A group of 25 researchers speculates that a comet exploded over ice-covered Canada 12,900 years ago and triggered a firestorm across North America that not only wiped out the Clovis people but also forced a number of large land mammals into extinciton and kicked off the Younger Dryas climate change. However, geologists are pretty conservative folks, according to the article, and some of them are not buying it.
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Did an Exploding Comet Doom Early Americans?

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  • by Podcaster ( 1098781 ) * on Tuesday May 22, 2007 @04:55PM (#19227475) Homepage Journal

    a comet exploded over ice-covered Canada 12,900 years ago and triggered a firestorm across North America

    According to TFA, the firestorm seems to be the most controversial part of their claims. All the dissenting voices in the article made mention of it.

    According to the abstracts [agu.org] of the research, it looks like the strongest evidence of a trans-american firestorm is "... a carbon-rich black layer commonly referred to as a black mat, with a basal age of approximately 12.9 ka, ... identified at over 50 sites across North America"

    -P

  • Now I don't pretent to understand this stuff but if there was a comet large enough to wipe out a people then surely we'd see a reduction in population across the globe due to dust blocking out the sun and such. We'd also be able to see it in the ground, whether it's less plant material or rocks/fossils.
    • by Eideewt ( 603267 ) on Tuesday May 22, 2007 @05:37PM (#19228185)
      Do you pretend to RTFA?

      The idea is that the comet started fires that wiped out these people. They would not have affected the rest of the globe hugely due to the interfering presence of oceans. Although you would expect the smoke of a burning continent to have an effect.

      According to TFA, the suggested impact happened at a time when "35 genera of the continent's mammals went extinct". Would that count as "seeing it in the ground?"
    • Re: (Score:1, Informative)

      by Anonymous Coward

      then surely we'd see a reduction in population across the globe due to dust blocking out the sun and such

      Maybe you're thinking of the results of a supervolcano? A comet that creates a firestorm that kills/chases off a group of people won't necessarily equate to planet-wide consequences. Strip a large enough area of much of its vegetation (doesn't even have to be all or even most vegetation) and you can kill off lots of animals and people who depend on that vegetation for shelter and food.

  • Well some of them were. You see this guy named John Smith appeared to one of them and told them to get out of the village.


    Either that or I've been watching too much TV lately, hmmm....
  • by jd ( 1658 ) <imipak@ y a hoo.com> on Tuesday May 22, 2007 @05:14PM (#19227787) Homepage Journal
    Just finished reading "The Map That Changed The World", the story of the discovery of plate tectonics. The reaction from the community was apparently not healthy skepticism but hostility bordering on fanaticism.
    • Re: (Score:2, Insightful)

      by fredrated ( 639554 )
      I remember picking up and looking over a geology text book circa 1950 at a garage sale. It said plate tectonics was full of crap, and said the same about another theory that escapes me. The other theory is also standard belief today. I didn't buy the book.
    • by gEvil (beta) ( 945888 ) on Tuesday May 22, 2007 @05:38PM (#19228209)
      I was going to make the same comment, but you beat me to it. I have a degree in Geology, and I remember my Historical Geology teacher telling us about how when he was in school nearly all of his professors ridiculed the idea of plate tectonics. However (according to him), he dismissed them as fools since the theory seemed to fit in so nicely with the available evidence. Just goes to show that the most important thing you can learn in school is to evaluate the data yourself.
      • Re: (Score:3, Funny)

        by nizo ( 81281 ) *
        Just goes to show that the most important thing you can learn in school is to evaluate the data yourself.


        Yes indeed! My math teacher told me that PI is an irrational number; as soon as I am done computing it out to infinity I will know this fact for myself, but until then I am still pretty skeptical.

        • I wish you the best of luck with that. Let us know when you get close to finishing...
        • He said "evaluate the data yourself", not "run off on a fool's errand". Mathematicians didn't conclude that Pi was irrational by trying to compute it's value and getting bored.

          • by nizo ( 81281 ) *
            Apparently my cynical unhumorous attempt to stir up a discussion about facts v.s. theories and the questioning thereof has utterly failed. For the record I agree with the grandparent post that sticking with a theory when it no longer fits the available facts isn't conducive to furthering our understanding of how things really work.
        • by jd ( 1658 )
          I told my computer to evaluate Pi once, but it got so irrational that it beat the machine up and kicked it downstairs. Which was impressive, as I lived on the ground floor at the time.
        • by broter ( 72865 )
          Funny joke, but pi is provably a transcendental number [wikipedia.org], which means it's irrational. Transcendental numbers are numbers that aren't the root an any rational polynomial. So, it's a mathematical proof, not a scientific theory. Big difference.

          If you care to check for yourself, Johann Heinrich Lambert [wikipedia.org] has a proof of it that I've never read. I hear it's painfully long.

          That's the great thing about math: unless it says "conjecture" it's provably true or false.
          • by broter ( 72865 )
            "...: unless it says "conjecture" it's provably true or false."

            For instance, that statement I made is totally false. How could I forget about Godel [wikipedia.org]'s theorem?

            Oh well, at least I'm making my daily allowance of mistakes.
        • by asninn ( 1071320 )
          Calculating all the digits is neither necessary nor would it be helpful; here [lrz-muenchen.de]'s a short proof of pi's irrationality, though.
      • by Temkin ( 112574 ) on Tuesday May 22, 2007 @05:49PM (#19228427)


        While I was wrapping up my Geology degree in the early 90's, I actually came across a old geezer with tenure at a symposium that kept rambling about granitizing fluids. Thankfully, he wasn't a prof at my school.

        It's been said that any major change in the fundamental theories of a field will not be accepted until the old guard dies off. Plate tectonics was one such shift. I figure if we're wrong about global warming, we won't be able to admit it until 2045 or so...

        • by nizo ( 81281 ) *
          It's been said that any major change in the fundamental theories of a field will not be accepted until the old guard dies off.


          Maybe something subtle, like a lunch symposia titled "Current Ideas in Granitized Fluids" where you serve poisoned food items would be a good idea now and then?


          I figure if we're wrong about global warming, we won't be able to admit it until 2045 or so...


          Yeah that would probably be pretty much too late either way.

          • by Temkin ( 112574 )

            Maybe something subtle, like a lunch symposia titled "Current Ideas in Granitized Fluids" where you serve poisoned food items would be a good idea now and then?



            Maybe... But I left the field. I was working on groundwater modeling, writing my own software, and there was this Finnish guy that released a free OS with a real VM system... and years of study was suddenly boring... I think that was kernel 0.95a. :-)

          • Re: (Score:2, Insightful)

            by Anonymous Coward
            It'll be cancelled out by an equally baseless prediction of "global cooling" in a few years. I think the only thing that's cyclical is idiocy in blindly believing the random end-of-world scenario du jour.

            Weathermen can't accurately predict the weather a few hours out ... what makes anyone think they can predict the temperature years or decades out?
            • Re: (Score:2, Informative)

              by jlehtira ( 655619 )

              Weathermen can't accurately predict the weather a few hours out ... what makes anyone think they can predict the temperature years or decades out?

              The weather a few hours out is about the distribution of mass and energy in our atmosphere.

              The temperature decades out is about the total amount of mass and energy in our atmosphere.

              You've got to admit that the latter is a much easier problem.

            • by Goaway ( 82658 )
              God, you people parroting the same tired, refuted-ad-nauseum arguments OVER and OVER and OVER...

              Christ! Make the slightest effort at rational thought, would you? Take a tiny little step towards finding something out for yourself instead of believing every pig-headed thing you hear on the internet that makes you feel good about yourself for being a contrarian.

              You want to complain about the "old guard" holding science back?

              YOU ARE THE FUCKING OLD GUARD!
            • Re: (Score:1, Insightful)

              by Anonymous Coward

              Weathermen can't accurately predict the weather a few hours out ... what makes anyone think they can predict the temperature years or decades out?

              Whatever you do, don't go into any of the scientific or business fields that rely on statistics. You can probably earn a good living designing web sites, or maybe as a plumber, or something similar, and you'll be a lot more comfortable with that.

              Or, accept a short period of intense discomfort and study statistics. Learn the key difference between describing a data point and describing the population to which it belongs.

        • granitizing fluids?

          Is that Hot grits?
      • I remember my Historical Geology teacher telling us about how when he was in school nearly all of his professors ridiculed the idea of plate tectonics. However (according to him), he dismissed them as fools since the theory seemed to fit in so nicely with the available evidence.
        Possibly the perfect example of Kuhn's view that sometimes the Old Guard just has to die off.

        But I don't think things are usually that bad. (Am I naive?)
        • by jd ( 1658 )
          But I don't think things are usually that bad. (Am I naive?)

          And now, a news report from 2145: "Researchers have finally established a correlation between advance bookings at cemetaries and the publication of new theories, a new report has said. When asked for comment, three aged critics of the claim were run over by a car registered to a student working for one of the new researchers."

        • Re: (Score:3, Insightful)

          It's not always that bad in science: some theories are accepted pretty quickly. The Dark Energy theory has gained wide-spread acceptance almost overnight. The Giant Impact theory for the formation of the Moon was accepted by much of the community over the course of a single meeting, I've been told by a participant.

          It seems to be a question of overwhelming evidence: if you don't have really compelling evidence, you'll have a slow, uphill battle. If you do, odds seem to be in your favor for gaining a much
          • Re: (Score:3, Interesting)

            by General Wesc ( 59919 )

            The Giant Impact theory for the formation of the Moon was accepted by much of the community over the course of a single meeting, I've been told by a participant.

            A quick search reveals that is the case [psi.edu]:

            Some work was done by Thompson and Stevenson in 1983 about the formation of moonlets in the disk of debris that formed around Earth after the impact. However, in general the theory languished until 1984 when an international meeting was organized in Kona, Hawaii, about the origin of the moon. At that meet

            • Yep, that was the meeting. My graduate adviser was there. He said that what really convinced people was the first suite of numerical models that showed that it was possible dynamically to make the Moon that way.
      • by Megane ( 129182 )

        and I remember my Historical Geology teacher telling us about how when he was in school nearly all of his professors ridiculed the idea of plate tectonics

        That's not the only geological idea that took mainstream scientists a long time to accept. [spokaneoutdoors.com]

      • by nagora ( 177841 )
        I have a degree in Geology, and I remember my Historical Geology teacher telling us about how when he was in school nearly all of his professors ridiculed the idea of plate tectonics.

        You have to remember that there were a ton of objections to plate tectonics which its supporters could not answer (where does new crust come from; where does old stuff go; where does the energy come from; etc.). Until new observations could solve these questions the evidence was not that strong and what there was gave no real

    • Re: (Score:2, Insightful)

      by zoikes ( 182347 )
      Horses**t:
            Theory X was controversial, but turned out to be true.
            Theory Y is controversial, therefore theory Y is true.

      Gimme a break.
      • by jd ( 1658 )
        How observant. The correct steps are:
        1. Theory X is not merely controversial but cynically rejected without ever being tested, yet turns out to be true anyway.
        2. Method of evaluating theories is deduced to be broken, as it becomes apparent that theories are being deemed false without having been falsified.
        3. Method is refined, the same way ALL theories are refined when they are found wanting.
        4. Theory Y is controversial, but examined from a more enlightened perspective. It turns out to be false, but it is found to
      • Re: (Score:2, Funny)

        by fractoid ( 1076465 )
        "You know how Einstein got bad grades? Yeah, well MINE are even WORSE!" - Calvin
    • Re: (Score:3, Insightful)

      by R2.0 ( 532027 )
      I remember reading about the history of plate tectonics in a Philosophy of Science class. Over in the Smithsonian thread, someone opined that "politics has no place in science". He obviously didn't read the same history we did.
      • by jd ( 1658 )
        Apparently they didn't read the same history as the ancient Greeks did, either. (Ok, ok, the Sumerians invented politics in general, but the Greeks invented both politics and science as we know them today - and mixed them freely. Usually with martinis. Or mead. One of the two.)
    • by Anthony ( 4077 ) *

      Erm, how well did you read it? That book, by Simon Winchester, was about William Smith, the first person to create a geological map. Also a case study of someone who lived beyond their means.

      Wegener certainly got a hard time for his continental drift theory. The mechanism, plate tectonics, was only pieced together 50 years later.

      Geologists are just like any other scientists. Conjecture (the continents are not fixed on the face of the earth) without a proven mechanism (expanding earth?, floating rocks?)

  • Looks like the firestorm even hit the other side of the world.

    So if humans want to survive things like this in the future we should go back to living deep in caves rather than tall exposed buildings.
    • by DohnJoe ( 900898 ) on Tuesday May 22, 2007 @06:32PM (#19229141)

      So if humans want to survive things like this in the future we should go back to living deep in caves
      I think most slashdotters are already aware of this danger, living in the safety of their parents basement ;)

      Teh community will be saved!!!
      • Re: (Score:2, Funny)

        by R2.0 ( 532027 )
        For 1 generation. Then the total lack of women basement dwellers will doom the race.
        • by Grishnakh ( 216268 ) on Tuesday May 22, 2007 @07:15PM (#19229633)
          That's why we need to become highly active in do-it-yourself genetic engineering. Then we can grow our own females in our basements. And our genetically engineered females will be superior to natural ones, as we can design them to be thin, beautiful, bisexual, and only interested in geeks (and other hot women).
          • Re: (Score:3, Funny)

            by DohnJoe ( 900898 )
            I guess the first words those women hear will be: 'please be gentle'
          • by pluther ( 647209 )
            Reminds me of the following which has been rattling around in my head for the last few decades.

            (I believe Isaac Asimov may be to blame for this)

            Oh, give me a clone
            Of my own flesh and bone
            With the Y chromosome changed to X
            And when she is grown
            My very own clone
            She will be of the opposite sex

            Clone, clone of my own
            With the Y chromosome changed to X
            And when we're alone
            Since her mind is my own
            She'll be thinking of nothing but sex.

            (Yeah, I didn't need all that karma anyway...

  • by andrewd18 ( 989408 ) on Tuesday May 22, 2007 @05:37PM (#19228191)

    According to results presented by a team of 25 researchers this week at the American Geophysical Union meeting in Acapulco, Mexico, that's where the Clovis people's doom came from.
    I definitely read this as:

    According to results presented by a team of 25 researchers this week, the American Geophysical Union meeting in Acapulco Mexico: that's where the Clovis people's doom came from.

    I hate it when my doom comes from American Geophysical Union meetings in Acapulco, Mexico.

  • Problem (Score:5, Informative)

    by KwKSilver ( 857599 ) on Tuesday May 22, 2007 @07:17PM (#19229651)
    Clovis peoples did not "go extinct." They spread put across the Americas and developed in to more locally adapted cultures. The Folsom point is a fairly obvious derivative of the Clovis point see here [texasbeyondhistory.net]. The Folsom point supplanted Clovis on the Lower Great Plains. From Missouri to the Atlantic coast the Dalton point is considered a direct outgrowth of Clovis, and on the western Gulf Coast, the San Patrice point seems to have filled the same role as the successor to Clovis. Aside from that, there is a lot of regional variation in Clovis itself prior to the emergence of Folsom, San Patrice etc.

    The Pleistocene megafauna did go extinct, but the causes of that have been argued back and forth since I was a student in the 1970s, and with no end in sight. Some have blamed Clovis and closely related groups in the Americas, and refer to these extinctions as the result of a Clovis "blitzkrieg." However, there's also evidence to suggest that some were headed down the drain before humans reached the Americas. Late Pleistocene environments were drastically different from today. The southwest was fairly moist, not a desert at all. The southeast was considerably drier than now and had fine-grained, micro-environments quite unlike anything seen today. All of those environments changed drastically, and the intricately intermingled mico-ecologies of the southeast disappeared, and any fauna dependent on that was toast (my 2 cents, there).
    • "Some have blamed Clovis and closely related groups in the Americas, and refer to these extinctions as the result of a Clovis 'blitzkrieg.'" I recall reading/hearing something about a similar "blitzkrieg" by the First human inhabitants of Australia. And more recently, the decimation of the Moa and other flightless birds in New Zealand. Point being, I think we underestimate the power even primitive humans had to drastically change their environments, especially ones they aren't native to. But I must say,
    • Re:Problem (Score:5, Informative)

      by Inexile2002 ( 540368 ) * on Wednesday May 23, 2007 @07:58AM (#19234279) Homepage Journal
      There is some indirect evidence that the Clovis culture died out even if some of the Folsom people were ancestors of the Clovis people. You say that the Folsom point is derivative of the Clovis point when most sources that compare the two note that the Folsom point was inferior to the Clovis. The vast majority of Folsom points were found using rock quarried from relatively local sources, where as the Clovis points are often found thousands of kilometers from the rock quarries that the stone originated from. Clovis peoples valued higher quality stone enough that they either traveled or engaged in VERY long distance trade to get it. They produced some of the most sophisticated stone tools ever developed by human beings, only really being surpassed by Pre-Colombian native Americans almost ten thousand years later. Finally, Clovis points with nearly identical workmanship have been found from Alberta to California to Patagonia and as far east as Floria - points that have been dated to within hundreds of years of years of each other. All of this indicates a sophisticated, wide ranging, traveling culture.

      The Folsom people by contrast didn't leave evidence of this type of wide ranging travel and sophistication, a change that seems to have happened quite quickly. Archaeologists have speculated that climate change led to conditions that were more hostile to longer distance travel - forcing them to use lower quality stone and thus simpler stone work techniques, but the evidence does seem to indicate the death of the Clovis culture (if not the people themselves). The true reasons for the sudden culture change will probably never be known. If there's good evidence of a Pliestocine comet explosion then it almost definitely was a nail in the coffin of the Clovis peoples.
    • by T.E.D. ( 34228 )

      They spread put across the Americas and developed in to more locally adapted cultures. The Folsom point is a fairly obvious derivative of the Clovis point..

      The way I remember my old Anthro course, the main distinguishing factor in Clovis was the "fluted" spear/arrow heads. This basicly means they had a trench in the sides, to help the very large mammals they got stuck in to bleed to death quicker. Once the very large mammals died out (for whatever reason), there was no longer a huge need for the fluting.

      The

  • Atlantis (Score:3, Interesting)

    by 12357bd ( 686909 ) on Wednesday May 23, 2007 @05:34AM (#19233607)
    So Plato [wikipedia.org] was right about a great disaster 9000 years before his epoch.
  • by DynaSoar ( 714234 ) * on Wednesday May 23, 2007 @12:49PM (#19239699) Journal
    The Navajo (Dine) people of the southwest US are directly related to the Dene of Canada. It's already been shown that it took the former over 20,000 years to migrate physically and linguistically. It's trivial to show the latter (in Canada, ground zero for the object in question) still exist.

    The Hopi (Anasazi or "Ancient Ones" in Dine) can confirm that the Dine/Dene were here over 20,000 years ago. They met these descendents of the Tungusk coming across the Bering Land Bridge. Since this means the Hopi were here before the Bridge, it doesn't get taken seriously. Likewise, the Dine's name for the Hopi is that of another group that supposedly went extinct, indicating they didn't, is another fact that gets actively ignored.

    Conducting archeology without conducting anthropology on people that still exist is like studying the history of New York by studying the subway maps and ignoring the people on the platforms and the streets above.
    • That the physical record does not coincide with data from linguistic analysis is one of the standing problems within the current scientific consensus regarding the first peoples of America. There are a variety of ways to account for this. One's view is sharply dependent upon one's academic specialty. Linguists obviously chafe at being told that phonetic evolution is perhaps not as controlled and deterministic a process as radio-isotope decay. Similarly, analysis of mutation within mitochondrial DNA has
      • by 12357bd ( 686909 )

        Sorry,but data is never complete. Mismatches between ancien traditions and current theories about what happened at a certain time frame, use to suffer the 'not modern' syndrome.

        Troy (and a lot of other important arqueological sites) was considered a mere myth, due to a miopyc s.XVIII prejudice still present due to the lack of proper philosophical studies in current education.

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