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Science

New Evidence About 'The Great Dying' 250 Million Years Ago 657

PornMaster writes "The Guardian is reporting that scientists have found the first direct evidence that the killoff of 80% of land species and 95% of marine species 2 billion years ago was due to a meteor." The project web site has more info, maps, etc.
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New Evidence About 'The Great Dying' 250 Million Years Ago

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  • So uh... A giant meteor hit the earth and all the dinosaurs turned into giant roasted chickens?
  • by Steve B ( 42864 ) on Friday May 14, 2004 @08:28AM (#9150367)
    New clues to 2bn-year-old murder
    A buried crater off Australia could be the first direct evidence of a celestial assassin that wiped out more than 80% of life on Earth 250m years ago.
    Obviously, Guardian headline writers follow the /. habit of not bothering to RTFA.
  • by swordboy ( 472941 ) on Friday May 14, 2004 @08:29AM (#9150375) Journal
    Mmmm... unprocessed gasoline...
  • Finally... (Score:5, Funny)

    by tommertron ( 640180 ) on Friday May 14, 2004 @08:29AM (#9150378) Homepage Journal
    They found the weapons of mass destruction!
  • by A Commentor ( 459578 ) on Friday May 14, 2004 @08:30AM (#9150390) Homepage
    If the poster would have read the first paragraph, they would have seen it was at 250 million years ago not 2 Billion...
    Scientists believe they are on the track of the biggest mass murderer in the two-billion year history of life. A buried crater off Australia could be the first direct evidence of a celestial assassin that wiped out more than 80% of life on Earth 250m years ago.
  • by WormholeFiend ( 674934 ) on Friday May 14, 2004 @08:31AM (#9150400)
    more than 80% of terrestrial life?

    more than 95% of marine life?

    that would mean that whatever we have today, evolved from >20% / >5% of those species that survived?

    that's a whole lotta evolution if you ask me.

    • 250mil years of evolution? That sounds about right.
    • by GMO ( 209499 ) on Friday May 14, 2004 @08:38AM (#9150504)
      The usual explanation is that the remaining species can diversify into the ecological 'space' left after the holocaust.

      In this view, in a crowded world, species are constantly in competition with each other, and diversity is held in balance, while in the time after a great extinction, all such constraints disappear, and species are free to do as they please.
      • by WormholeFiend ( 674934 ) on Friday May 14, 2004 @08:41AM (#9150559)
        how do they really know the 100% part of the equation though? if you don't know the total number of species there was to start with, you cant estimate the remaining portions after the extinction event. I'm pretty sure a life-extinguishing asteroid would vaporize a lot of evidence in a large radius around ground zero.

        and scientist don't even know for sure the total number of different species we have right now... it's all estimates, as new species are discovered every day.
      • It can also mean (with exception offcourse) that the strongest were able to adapt and survive. Now obviously a species in the direct range of the blast would be toast, but those who are suffering from the "nuclear winter" would have to follow the "survival of the fittest" model. Especially with scarce food, oxygen, light, etc. Pretty impressive if you ask me....then again most of those life forms are probably bacteria, & cockroaches(the equivelant of), etc...
    • by Chemisor ( 97276 ) on Friday May 14, 2004 @08:39AM (#9150530)
      Look at it another way: this just means that 80% of terrestrial life and 95% of marine life are completely useless.
      • this just means that 80% of terrestrial life and 95% of marine life are completely useless

        I could have told you _that_. It's a simple corollary of Sturgeon's Law: 90% of everything is crap, there's 4 times as much life in the sea as there is on land, so 80% of terrestrial life and 95% of marine life are completely useless.
    • WHAT?!? somebody actually questions the theory of evolution?? He must be a fundamentalist! Off with his head!

      actually, if you look at the hard evidence, the whole concept of macro-evolution is nothing more than a wild guess in the dark. the theory is full of holes and most of the logic doesn't completely add up. but i guess people have to believe in something.
    • Actually evolution is a myth, it's made up science. Don't believe me? Prove me wrong then. I'll pit the Holy Bible against the theory of evolution or "The Big Bang" any day. Yep, yet another example of junk science just like Global Warming.

      Before you people get started...This post is not an attempt to start a flame.

      -=GuestFox=-

    • more than 80% of terrestrial life? more than 95% of marine life? that would mean that whatever we have today, evolved from >20% / >5% of those species that survived? that's a whole lotta evolution if you ask me.

      I guess it depends on if you believe the article,which says % of LIFE, or the poster's interpretation which assumed it meant % of all SPECIES.

      Big difference.

    • by Daniel Dvorkin ( 106857 ) * on Friday May 14, 2004 @10:21AM (#9151738) Homepage Journal
      Take a look at some of the Cambrian Explosion fossils. There was a greater diversity of animal life at that time than at any time before or since, including our own era. Most of those species died off (presumably without any help from a Big Rock, just because they weren't all that well-suited to their environments) and the few basic body plans of modern animal life were the ones that went on to form the foundation for all future generations.

      Life is always experimenting with greater diversity; in times of low diversity, as after great die-offs, the existing forms will quickly branch out to fill the available ecological niches. There does, however, seem to be an upper bound as well, as the Cambrian shows.
  • Did they find evidence of offshore outsourcing?
  • My bad (Score:5, Funny)

    by AtariAmarok ( 451306 ) on Friday May 14, 2004 @08:32AM (#9150420)
    I knew I should not have put that giant can of Lysol in the time machine. But I did it anyway. Sorry.
  • by Spock the Vulcan ( 196989 ) on Friday May 14, 2004 @08:32AM (#9150421)
    When I heard the story on NPR yesterday, it said the event was dated at around 250 million years ago. That's what the body of the linked article says too. Somehow, the headline has been changed to say 2 billion. Funny.
  • Not 2 BILLION! (Score:4, Informative)

    by goatbar ( 661399 ) on Friday May 14, 2004 @08:32AM (#9150425) Homepage
    Minor correction: The Permian wasn't 2 billion years ago. Geologic Timescale. The Permian was in the neighborhood of 286 to 248 million years ago.

    There wouldn't have been much on land at 2Ga.

  • Hogwash (Score:2, Insightful)

    by Anonymous Coward
    "...scientists have found the first direct evidence..."

    Direct evidence my arse. Scientists have found a few holes in the ground and some sediments. It amazes me that so many people just blindly accept these theories (and they are only theories) about meteors wiping most of the life out on earth long ago.

    • "Blindly accept"? (Score:3, Informative)

      by dustmite ( 667870 )

      Could you explain exactly who is "blindly accepting" these theories? We all know they're "just theories".

      BTW they found a bit more than just "sediments" and a "few holes in the ground". It does seem likely in fact that they have found a meteor impact crater, just not necessarily one that resulted in a major extinction.

  • Two billion years ago there existed only prokaryotic bacteria. The impact the articles are talking about was the end of the Permian era. It happened about 250 million years ago (as stated in the article). Both the Guardian's and Slashdot's articles are mistitled.

  • Verneshot (Score:3, Interesting)

    by seanyboy ( 587819 ) * on Friday May 14, 2004 @08:34AM (#9150458)
    So... It's a big meteor, or a volcano or maybe, just maybe... It was caused by a verneshot [ananova.com]
    • While the verneshot idea sounds nice, and may explain some incidents, I think it's a bit too unlikely. The article there was on them in New Scientist a couple of weeks ago left me singularly unconvinced - especially when they resorted to suggesting the 1908 Tunguska event was a verneshot (completely ignoring the fact that people saw a flaming object heading towards the explosion location rather than away from from it as you'd get with a verneshot...)

      Nah, when they find solid evidence of a verneshot pipe I'
  • I wonder... (Score:4, Funny)

    by Woogiemonger ( 628172 ) on Friday May 14, 2004 @08:36AM (#9150473)
    I wonder if historians 2 billion years from now will come to a similar conclusion when they find the 125 mile-wide crater in Redmond.
  • by thatguywhoiam ( 524290 ) on Friday May 14, 2004 @08:37AM (#9150499)
    .. out of curiosity.. how big that rock was?

    You never really see figures about how fast, and how big that chunk of rock (?) was. Gimme a nice scientific factoid, in standard Volkswagen units or something.

    • Is it ironic that a culture that can't standardize on metric or imperial (or whatever inches are) can standardize on the "width of the human hair" and "volkswagens"?

      -WS
  • by BrownDwarf ( 615206 ) on Friday May 14, 2004 @08:38AM (#9150503)
    Finding a very thin layer of irridium in the rocks laid down at the very end of the Permian would be compelling evidence. A layer of irridium, together with the crater in the Gulf of Mexico off the Mexican coast, made a good argument of what caused the dinosaurs to go at the end of the Cretaceous period.
  • by heir2chaos ( 656103 ) on Friday May 14, 2004 @08:39AM (#9150520)
    So, a giant meteor crashes off the coast of a continent that has some of the strangest creatures on the planet, Austrailians. Oh, and think of all the weird animals there too.
  • BBC link (Score:5, Informative)

    by Anonymous Coward on Friday May 14, 2004 @08:39AM (#9150523)
    The BBC have a much better version of the same story with addition information and some on the opposing view points BBC.co.uk [bbc.co.uk]
    • by JPMH ( 100614 )
      The story also has an article [economist.com] in the Economist this week.

      The article mentions an interesting theory, that instead of an external meteorite triggering mass eruptions, it might be the volcanic eruptions that came first. The eruptions were powerful enough to fire a great gob of rock into space, and each big crater is where it re-impacted. On this view the eruptions would be the prime cause of the mass extinctions - at Permian, Cretaceous and Triassic - and the impact craters just a side effect.

  • Lies.. (Score:2, Funny)

    by Anonymous Coward
    The earth was created in 7 days. Dinosaurs are a fabrication by atheists. God is perfect and didn't need to practice by making Dinosaurs, you twits. The fact is that they never existed!
    • Re:Lies.. (Score:3, Funny)

      by cbiltcliffe ( 186293 )

      The earth was created in 7 days.

      True, but who's definition of a day are we going by here? An Earth day, a Saturn day, or a galactic day? Then there's the whole biblical "A day is as a thousand years" thing.

      Dinosaurs are a fabrication by atheists.

      Who, besides you, ever said this? Dinosaurs did exist, they just weren't millions of years before people... http://www.genesispark.com/genpark/foot/foot.htm [genesispark.com]

      God is perfect and didn't need to practice by making Dinosaurs, you twits.

      God is perfect, but

  • Effects (Score:5, Informative)

    by krymsin01 ( 700838 ) on Friday May 14, 2004 @08:40AM (#9150544) Homepage Journal
    I stuck some data in the impact effects simulator (http://www.lpl.arizona.edu/impacteffects/), took reasonable guess at most of it. Anyone else more knowledgable, please correct.

    Distance from Impact: 1000.00 km = 621.00 miles
    Projectile Diameter: 28280.20 m = 92759.06 ft = 17.56 miles
    Projectile Density: 3000 kg/m3
    Impact Velocity: 30.00 km/s = 18.63 miles/s
    Impact Angle: 45 degrees
    Target Density: 3000 kg/m3
    Target Type: Competent Rock or saturated soil

    Energy:
    1.60 x 1025 Joules = 3.82 x 109 MegaTons TNT
    The average interval between impacts of this size somewhere on Earth is 2.6 x 109years

    Crater Size:
    Transient Crater Diameter: 173.30 km = 107.62 miles
    Final Crater Diameter: 340.69 km = 211.57 miles
    The crater formed is a complex crater.

    Thermal Radiation:
    Time for maximum radiation: 16.79 seconds after impact
    Visible fireball radius: 425.5 km = 264.2 miles
    The fireball appears 96.7 times larger than the sun
    Thermal Exposure: 6.13 x 108 Joules/m2
    Duration of Irradiation: 655 seconds
    Radiant flux (relative to the sun): 936.0

    Effects of Thermal Radiation:
    Clothing ignites
    Much of the body suffers third degree burns
    Newspaper ignites
    Plywood flames
    Deciduous trees ignite
    Grass ignites

    Seismic Effects:
    The major seismic shaking will arrive at approximately 200.0 seconds.
    Richter Scale Magnitude: 11.0 (This is greater than any earthquake in recorded history)
    Mercalli Scale Intensity at a distance of 1000 km:
    VI. Felt by all. Many frightened and run outdoors. Persons walk unsteadily. Windows, dishes, glassware broken. Knickknacks, books, etc., off shelves. Pictures off walls. Furniture moved or overturned. Weak plaster and masonry D cracked. Small bells ring (church, school). Trees, bushes shaken (visibly, or heard to rustle).
    VII. Difficult to stand. Noticed by drivers of motor cars. Hanging objects quiver. Furniture broken. Damage to masonry D, including cracks. Weak chimneys broken at roof line. Fall of plaster, loose bricks, stones, tiles, cornices (also unbraced parapets and architectural ornaments). Some cracks in masonry C. Waves on ponds; water turbid with mud. Small slides and caving in along sand or gravel banks. Large bells ring. Concrete irrigation ditches damaged.
    Masonry C. Ordinary workmanship and mortar; no extreme weaknesses like failing to tie in at corners, but neither reinforced nor designed against horizontal forces.
    Masonry D. Weak materials, such as adobe; poor mortar; low standards of workmanship; weak horizontally.

    Ejecta:
    The ejecta will arrive approximately 494.4 seconds after the impact.
    Average Ejecta Thickness: 9.4 m = 30.83 ft
    Mean Fragment Diameter: 5.4 mm = 0.2107 inches

    Air Blast:
    The air blast will arrive at approximately 3333.3 seconds.
    Peak Overpressure: 920445.5 Pa = 9.2045 bars = 130.7033 psi
    Max wind velocity: 661.5 m/s = 1479.8 mph
    Sound Intensity: 119 dB (May cause ear pain)

    Damage Description:
    Multistory wall-bearing buildings will collapse.
    Wood frame buildings will almost completely collapse.
    Multistory steel-framed office-type buildings will suffer extreme frame distortion, incipient collapse.
    Highway truss bridges will collapse.
    Highway girder bridges will collapse.
    Glass windows will shatter.
    Cars and trucks will be largely displaced and grossly distorted and will require rebuilding before use.
    Up to 90 percent of trees blown down; remainder stripped of branches and leaves.

  • Actually..... (Score:5, Informative)

    by RevSin ( 709070 ) on Friday May 14, 2004 @08:42AM (#9150569)
    This article is incorrect convieniently(sp?) enough I was listening to the NPR talk show yesterday and they very clearly said that is was 250 million years ago, which they said was the same that the tested core samples came out to be. They found the site they believed was it a crater on the sea floor with nearly a mile of dirt ontop of it, by using the same techniques that people looking for oil would. Incidentally the core samples were obtained 60 years ago while doing oil prospecting.

    Hope that's atleast a little informative.

    -RevSin
  • Wow, clues to a 2-billion-year-old murder? Sounds like Angela Lansbury's first case...
  • Doesn't this just sound like the title of the latest "Land Before Time" flick, the cartoon series about the dinosaur kids?

    Maybe it's the final one in the series.
  • The great dying didn't kill everything. Dinosaurs still walk among us. Here's an example, Gary Condit [tdi.net], a gentleman with the appearance and predilections of a T-Rex [visit-chic...linois.com]. The facial resemblance is striking.
  • Scientists didn't find a way to blame President Bush and Republicans for this. At least they could have come up with Dick Cheney and a time machine or something. The last thing we can have is "nature" causing extinctions, it has to be Republicans and SUV drivers! Get with the program!!!
  • by VernonNemitz ( 581327 ) on Friday May 14, 2004 @08:57AM (#9150742) Journal
    Years ago, when Mariner 10 went and disovered the Caloris Basin and wierd terrain on Mercury [senecac.on.ca], I immediately wondered if something like that could happen on Earth. I was one of the first to notice that the volcanic Deccan Traps that formed in India at the time of the dinosaur extinction just happened to be located (after taking contintental drift into account) on the opposite side of the Earth from Chixulub. (As I recall, I wrote a letter to Scientific American [sciam.com] about it, way back then...but they didn't think it publishable) And now the evidence seems to be accumulating, in favor of exactly such scenarios.
    • Forgot to say... (Score:3, Interesting)

      Now we have the volcanic Siberian outpourings of the Permian era, accompanied by a giant meteor impact in Australia (and after taking 200 megayears of continental drift into account, they could well have been on opposite sides of the Earth at that time).
  • by Thunderstruck ( 210399 ) on Friday May 14, 2004 @09:02AM (#9150786)
    I am reminded of my undergraduate geology professor's first lecture to our class. He took a candle and covered it with a jar. The candle went out. Then he asked the class for a show of hands, how many people thought the candle went out because all of the available oxygen had been consumed, and how many people thought the flame ceased because (if memory serves) the jar had become saturated with phogistan. Of course the vote was 100% for the oxygen answer. He then explained that 100 years ago, we all would have failed the exam. He then went on to discuss "vestigal organs," the fossil record, and other models that have not held up well in all cases.

    His point? "Evidence" can often be made to support any number of theories, among them the 4.5 billion year age of the earth or in this case the cause of a mass extinction. In the future we will know more, but we should never assume we have all the answers right now.
    • That's just it. Good science (as opposed to junk science) does not assume anything of the sort.

      You observe. You collect evidence. Then you interpret the evidence to see if it matches any posited hypothesis. Usually, you put forth an hypothesis first, and then you test to see if your evidence fits.

      You do not massage data to make it fit, unless you have an agenda to fulfill.
  • by loopkin ( 267769 ) on Friday May 14, 2004 @09:18AM (#9150975) Homepage
    Actually, several clues tend to prove a meteor isn't the cause of permian extinction. For instance, there should be a thin layer of irridium (or any other stuff) coming from the meteor or its explosion/impact, and laying on the ground after the blast... Also their proof about having found the meteor impact site doesn't seem very convincing.
    Now, they need to explain why we don't find such clues, and they haven't done it yet.

    For now, the only convincing scenario involves volcanism and oceanic methan tanks (methan is stored inside ocean, both dissolved and inside seabed).
    Big volcanism activity in what is today Siberia (and there are proofs of it) increases mean temperature for about 5-10 C by producing greenhouse effect. Then with such increase, methan starts to evaporate from ocean, induces more greenhouse effect, and mean temperature goes up 5-10C more. At the same time, it kills life in the ocean.
    That 10-20C increase in mean temperature is enough to kill 80% of species on the surface of the ground.
    So that scenario explains everything better than the meteor theory.

    Forgive my bad English... I think that this explanation could be found on some american scientific website, so feel free to post the link.
    Oh, and you can find more info there [campusprogram.com]
  • Prevention (Score:3, Funny)

    by Syberghost ( 10557 ) <syberghost@@@syberghost...com> on Friday May 14, 2004 @09:41AM (#9151263)
    In order to keep this from happening to us, we need to:

    1) Advance as far technologically as we can, as fast as we can, especially in manned space travel.

    2) Learn how to survive with a polluted atmosphere, instead of just avoiding polluting it in the first place, which would retard technological growth.

    3) Get as many people the hell off this rock as fast as we can. A moonbase would be a great start.

    So, if you want the human race to become extinct, vote for John Kerry. If you want us to survive, vote for George Bush.

    Thanks for your support.

Keep up the good work! But please don't ask me to help.

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