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Space Science

Dinosaurs Died Within Hours of Asteroid Impact, says New Study 862

Posted by CowboyNeal
from the sudden-climate-changes dept.
colonist writes " reports that most dinosaurs were incinerated within hours by the 'heat pulse' of an asteroid impact 65 million years ago. The study 'Survival in the first hours of the Cenozoic' presents a scenario where the only survivors were underground or were underwater in swamps or oceans. All unprotected creatures were 'baked by the equivalent of a global oven set on broil.'"
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Dinosaurs Died Within Hours of Asteroid Impact, says New Study

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  • by nightsweat (604367) on Thursday May 27, 2004 @06:27PM (#9272149)
    An appropriate post for the Memorial Day weekend. Imagine the world's largest barbeque.
    • by sharkey (16670) on Thursday May 27, 2004 @09:42PM (#9273638)
      Imagine the world's largest barbeque.

      Mmmmm. Ribs big enough to tip over your car at the drive-in.

  • Broil? (Score:5, Funny)

    by turgid (580780) on Thursday May 27, 2004 @06:27PM (#9272152) Journal
    For us ignorant Brits, wthat's that in Gas Mark?
    • Re:Broil? (Score:3, Informative)

      by sense_net (755855)
      Broil is when you put the food directly under the flames.
    • Re:Broil? (Score:3, Interesting)

      by Doc Ruby (173196)

      "'Twas brillig, and the slithy toves
      Did gyre and gimbol in the wabe."

      British []? Broil is what you do at 4 o'clock in the afternoon [].
    • Re:Broil? (Score:3, Interesting)

      by terrymr (316118)
      Ok - I'm an ignorant Brit that lives in the US.

      Broiling is what the English call grilling.

      Of course a grill over here is one of those outdoor things with charcoal (or gas).
  • RTFA (Score:5, Funny)

    by lexsco (594799) on Thursday May 27, 2004 @06:28PM (#9272161)
    I'd like to RTFA, I really would !
  • by chaos421 (531619) on Thursday May 27, 2004 @06:28PM (#9272162) Homepage Journal
    it's too bad their all-star oil drilling team didn't quite make it in time...
  • by Goalie_Ca (584234) on Thursday May 27, 2004 @06:28PM (#9272166)
    At least the dinosaurs went out baked!
  • by mythosaz (572040) on Thursday May 27, 2004 @06:29PM (#9272173)
  • Survival (Score:5, Funny)

    by jimmcq (88033) on Thursday May 27, 2004 @06:31PM (#9272188) Journal
    Alright, so what do I need to survive the next major asteroid impact of this magnatude? It sounds like most buildings won't be sufficient protection.

    Do I need a cave to hide in? Should I go to a large body of water?
    • Re:Survival (Score:3, Interesting)

      by WiPEOUT (20036)
      I may have missed something, but from what I gathered, a concrete building with no significant wood or plastic exterior components should provide the occupants.

      The article stated that ground-level temperatures were only ~10K higher than just prior to the event. That's no big deal, save maybe during summer in parts of the world.

      Any building that didn't itself burn due to the IR radiation would shield it's occupants quite well. Concrete/Brick's transmission of IR radiation wouldn't be much more than that of
    • Re:Survival (Score:5, Interesting)

      by f97tosc (578893) on Thursday May 27, 2004 @07:09PM (#9272493)
      Alright, so what do I need to survive the next major asteroid impact of this magnatude? It sounds like most buildings won't be sufficient protection.

      Unless you are on the wrong side of the planet (in which case you are f*cked anyway), your building should be the least of your worries.

      Global food production will probably take a very deep dive as large areas get drenched/ baked and exposed to a bunch of other nastiness. Maybe the sky will go dark for some days or years also.

      We humans being what we are (animals with a strong urge to survive) one can probably expect violence and war for remaining food, and lots of refugees as some parts suck worse than others.

      Maybe you should look for a place far inland, a descent house, keep some water and purification equipment, plenty of food, and I'm sad to say, weapons.

      • by John Harrison (223649) <> on Thursday May 27, 2004 @09:04PM (#9273398) Homepage Journal
        A recent asteroid impact article on /. pointed out something that I had never thought of before. The two worst places to be after a major impact are under the impact and on the opposite side of the planet from it. Why is this? The debris that the impact throws up will travel out from the site of impact and some bits will go a long ways and other bits not so far. In any case, if you are 1/4 of the circumference of the earth from the site the debris can only come from one direction, but if you are 1/2 the circumference of the earth from the impact (opposite side of the earth) debris will be coming in from all directions. Some won't make it that far and some will fly even further, but it is the most likely place to get hit.

        This is easy to visualize if you imagine a strike at the North Pole and the debris traveling along the lines of longitude to the South Pole.

    • by chiph (523845)
      Just practice your "Duck and Cover" drill like Bert the Turtle []

      Or get one of the 1950's vintage A-Bomb-proof school desks.

      Chip H.
  • by Anonymous Coward on Thursday May 27, 2004 @06:32PM (#9272198)
    The Emeril Lagassaurus Rex would have added some prehistoric garlic when he saw the meteor coming...then BAM!!!! Another notch!
  • by scdeimos (632778) on Thursday May 27, 2004 @06:33PM (#9272209)
    "Hey, Lou, what the F is " *SPLAT*
  • Article title (Score:4, Informative)

    by SageMadHatter (546701) on Thursday May 27, 2004 @06:35PM (#9272226)
    Dinosaurs Fried Within Hours of Cosmic Collision, Study Concludes

    According to the article, the dinos were cooked by super-heated air. That would mean they were broiled, not fried :)
  • Facts? (Score:4, Insightful)

    by Racer X (140445) on Thursday May 27, 2004 @06:35PM (#9272230)
    This article contains the following quote:

    "There's no question over whether an asteroid hit. The roughly 6-mile-wide (10-kilometer) space rock carved out the Chicxulub crater off Mexico's Yucatan Penninsula."

    But fairly recently there was another article posted on slashdot, about the alleged impact having occurred in (what is now) Australia. (check, e.g., here for a similar story.)

    so what is the consensus *really*, in the scientific community? or is there just none?

    • Re:Facts? (Score:5, Informative)

      by WhytTiger (595699) on Thursday May 27, 2004 @06:38PM (#9272254)
      the consensus is: The asteroid that killed off the dinosaurs is the one that hit in the Yucatan Penninsula The asteroid that killed off 99.9% of life before the dinosaurs existed was the one that hit near austrailia
    • Re:Facts? (Score:5, Informative)

      by MoralHazard (447833) on Thursday May 27, 2004 @06:47PM (#9272334)
      I think you're talking about two different mass die-offs. The Yucatan crater theoretically caused the Late Cretaceous die-off (approx. 65 million years ago) that made the dinosaurs go extincet. The Australian crater has been linked to the Late Permian die-off, which happened about 250 million years ago.

      So, Racer X, the scientific community would appear to have two consensuses (consenses? WTF?), one on each of the two issues.

      Mass extinctions are a fairly regular event in the Earth's geologic history. There are at least two more, besides the Permian and Cretaceous catastrophes, with which I'm familiar. Most people only get taught about the Cretaceous one in high school, though, so they never hear about the others.

      Kind of like the Ice Age. Up until I was 16, I only thought there was one. Turns out there were a shitload of them.
    • Re:Facts? (Score:4, Informative)

      by anrwlias (783535) on Thursday May 27, 2004 @06:56PM (#9272404) Homepage
      You are confusing two different craters. The Chicxulub crater is generally considered responsible for the KT (Cretaceous/Tertiary) extinction that killed of the dinosaurs. The newly alleged impact crater off of Australia (there's still controversy over whether it is, in fact, an impact crater as opposed to the remnant of a volcano) is being considered as a cause of the P/T (Permian/Triassic) extinction that happened approximately 251 million years ago. The Permian extinction is notable for being the largest mass extinction on record. Some 95% of all species apparently died out in less than a million years (how much less is a source of controversy). This compares to only 50% for the K/T extinction.
  • Of course I didn't read the article, as I don't subscribe and am lazy, but wouldn't the heat kill all the plants too? And I thought there were "many" survivors. Mostly small animals, besides plants and lower life forms. And how could 1 impact effect the entire planet with such a high amount of heat? Wouldn't that metemorph rocks as well? Or even react the atmosphere?
    • by DragonMagic (170846) on Thursday May 27, 2004 @06:45PM (#9272322) Homepage
      Plus, if it were that powerful to bake animals, would not the water temperature rise, and the air bake the animals which did survive, and destroy the birds as they're not too good about going underwater, and melt the ice at the caps, and...

      Sorry, but this theory doesn't even sound plausible. What could they base it on? (Sorry, article /.'ed)
      • by CaptainCarrot (84625) on Thursday May 27, 2004 @07:06PM (#9272474)
        A brief heat pulse wouldn't raise the water temperature much, but even a rise of a few degrees might cause a number of more sensitive species to die off. Which may well be what happened.

        I don't know about the birds, but this is hardly a fatal objection. Small animals can find many hiding places unavailable to larger ones. I don't think we need be too surprised if a number of smaller dinosaur species survived.

        There were no polar ice caps during the Mesozoic.

        I'd be shocked to discover that's servers were ever overloaded by /. If you don't want to read the article, then say so. (If you're referring to the original paper, you can only get the abstract without a paid subscription anyway.)

      • by ultramk (470198) <> on Thursday May 27, 2004 @07:34PM (#9272735)
        Plus, if it were that powerful to bake animals, would not the water temperature rise, and the air bake the animals which did survive, and destroy the birds as they're not too good about going underwater, and melt the ice at the caps, and...

        To kill most large animals, the air doesn't need to be hot enough to bake the whole animal, just ruin its lungs.

        Plants are easy. Many (most?) plants have evolved mechanisms to allow them to survive forest fires, brush fires and the like. The root stock would survive, and the seeds are mixed with soil/blown into protected places etc. Remember, they don't all have to survive, just enough to repopulate the species. There would be myriad places where plants or animals would be sheltered by the shape of a canyon/cave or whatever.

        There are quite a few bird species that live in burrows/caves/hollow logs etc which would have survived. There are a lot of bird species that respond to any danger by diving into the water, and diving deep. Grebes, cormorants, and the like. There are lots of diving birds.

        As far as raising the temperature of the water, you're vastly underestimating the amount of energy it would take to raise the temperature of all of the earth's oceans. It takes a lot more energy to raise the temperature of a volume of water than it takes to raise the same volume of air the same amount. (any physicists/chemists/engineers want to run the numbers?) The surface temperature of the oceans would probably rise a bit, then most of that energy would be shed back into the atmosphere by evaporation. The overall temp of the oceans would remain pretty constant, certainly not enough to melt the ice caps. For the superheated air directly above the glaciers, there would probably be a little bit of surface melting, which would immediately refreeze, leaving a glazed surface.

        • by Julian352 (108216) on Thursday May 27, 2004 @07:48PM (#9272849)
          To be more exact for your "a lot of energy" required to raise water over the air - it is about 4 times as much energy for water than air. That is because the specific head of fresh water is 1 (Ocean water is .93) while the specific heat of air is only .25. Thus it takes 4 times as much energy to raise 1g of water 1 degree Celcius as compared to a gram of air.

          This doesn't at all take into the account the fact that the starting temperature of the air is higher than that of the water. The average temperature of water in the oceans is just a bit above freezing in the pole areas and is about 17C(62F) on average (max 36C). The average temperature of air is much higher due to being over landmasses. Thus heating all of the air is MUCH easier than water.
    • by RedWizzard (192002) on Thursday May 27, 2004 @07:25PM (#9272654)
      Of course I didn't read the article, as I don't subscribe
      The article would have answered your questions.
      And how could 1 impact effect the entire planet with such a high amount of heat?
      It was a very large impact. They estimate an object 10km in diameter, which left a crater 200km in diameter. They believe that material ejected during the impact actually reached suborbital altitudes and that much of the heat was generated by the friction of re-entry.
      Wouldn't that metemorph rocks as well?
      From the article: "Previous work uncovered a global layer of material that had melted and then hardened when the impact vaporized terrestrial rock."
      Or even react the atmosphere?
      Not sure what you mean by that. They think the energy involved would have heated the atmosphere enough to cause widespread death, but that would require temperatures 100 degrees C.
  • by GOD_ALMIGHTY (17678) <> on Thursday May 27, 2004 @06:42PM (#9272289) Homepage
    The majority of the dinosaurs were instantly fried, like in a nuke blast that wrapped around the globe. I haven't seen a movie lately, that had those kind of cool FX. How about you?

    Think about to all the meteor's crashing into earth movies there are, now think about all the FX. Nothing as impressive as ALL THE DINOSAURS getting fried as a heat wave travelled around the globe.

    Why can't Hollywood just pay attention to history and science. It's way cooler than the drek they come up with.

    But seriously folks, just think of all the Brontoburgers. I bet Fred and Barney boiled off the surface still salivating at the endless plains of dino ribs.
  • But so much survived (Score:5, Interesting)

    by DeadBugs (546475) on Thursday May 27, 2004 @06:42PM (#9272291) Homepage
    So many things survived from that time other than the Dinosaurs. Large trees, many forms of reptiles and mammals that are virtually the same (based on fossil records) to this day.

    Not too mention that the fossil records for Dinosaurs don't stop on 1 day.

    It seems that the Doomsday theory gets more headlines than other theories suggesting, disease and climate change (a much slower, more boring process) were the cause. Even though the damage of a meteor strike would have been far more devastating and left the planet set back near square one as far as life.

    If the earth was baked and then the sun was blocked by smoke and ash, how come so much survived?

    *Note IANAS (I Am Not A Scientist), just wondering.
  • by NoMoreNicksLeft (516230) <john,oyler&comcast,net> on Thursday May 27, 2004 @06:43PM (#9272299) Journal
    Is how they ever managed to live in the first place. The strength of muscles is a function of the area of their cross-section. It increases only roughly at a rate of the square of its size. Weight goes up as a cube of its size. Things get heavier much faster than they get stronger.

    And just how much stronger could dino muscles have been than modern mammalian muscle? 140% stronger, 170%? That's really stretching it, and it still isn't nearly enough.

    Land animals probably can't be much bigger than an elephant.

    And no, I'm not a christian scientist. I don't think it's a conspiract, the bones are there, and they show how big the things must have been. I'd just like answers (prefereably those that don't have anything to do with superstitious bible crap).
    • by jebell (567579) on Thursday May 27, 2004 @06:49PM (#9272357) Journal
      And just how much stronger could dino muscles have been than modern mammalian muscle? 140% stronger, 170%? That's really stretching it, and it still isn't nearly enough.

      I think you're underestimating how strong many animals really are. Our close relatives, the chimpanzees, are considerably stronger, pound-for-pound, than we are. Reptiles are also noted for being very muscular, even if they don't have much stamina.

    • by 0xffffffff (161827) on Thursday May 27, 2004 @06:53PM (#9272385)
      There is a theory that the earth was lighter back then, which let heavier animals thrive. It's an interesting theory - it also says that the Pangea continent covered the whole earth (not just one side) since the earth was ~40% of it's current size, and that it grew by collecting space debris over time. Someone should do the math concerning muscle efficiency and this ancient mass of the earth and see if it works out.
    • by eviloverlordx (99809) on Thursday May 27, 2004 @07:16PM (#9272540)
      But the fact is, that land animals larger than elephants have, in fact, existed. Mass does indeed go up as a cube of length, but land animals (dinosaurs included) aren't just cubes of flesh and bone. If you take the large amount of non-solid space in the lungs and gastro-intestinal system, you do reduce the density, and therefore the mass by an extent.

      There is quite a bit of research going on in this area that relates to dinosaurs. I don't have any specific refs, but if you check out the recent literature, you should be able to find a number of current articles.
    • by Ungrounded Lightning (62228) on Thursday May 27, 2004 @07:55PM (#9272911) Journal
      And just how much stronger could dino muscles have been than modern mammalian muscle? 140% stronger, 170%? That's really stretching it, and it still isn't nearly enough.

      When doing comparisons be careful to avoid human muscle. Humans are cursorial hunters (jogging after their prey until it collapses from heat exhaustion.) Most of their muscles are set up to only use a few percent of their fibers at a time - and switch to another batch when the first run out.

      That's why hysterical strength is so much greater: Under great stress you CAN use your whole muscle power for a few contractions - like a mother lifting a car off her kid (a rather common event, actually). But it comes at a cost: The bones, pads between them, and muscle attachments are NOT built to the necessary strength for this. Use of hysterical strength normally means some serious, often permanent, injury.

      Most other animals (including even our close relatives the chimps) use a much higher fraction of their muscles all the time - or under only moderate provocation - and have the structure to support this use. (That's why they're so dangerous to people who handle them without having armor on and weapons handy.)

      Land animals probably can't be much bigger than an elephant.

      Not if they're going to be chased around by lion prides, packs of canids, and humans. (The square-cube law also applys to dumping heat.) You can build a workable animal MUCH bigger than an elephant. But now that there are warmbloods specializing in running things to collapse and eating them you can't keep a population of things that large viable in the wild.
    • I'm still confused on why *all* the Dinosaurs died 65 million years ago, yet the rest of land animals (amphibians, reptiles, mammals, and birds) survived.

      Dinosaurs weren't all big dumb lumbering brutes -- some were as small as our present-day reptiles and amphibians, and had mostly the same environment. Ne'ermind that at least one of the reptiles had a brain/body mass ratio better than a wolf.

      So why did every dinosaur die but reptiles survived? Why did every dinosaur die but birds survived?


  • Thank God (Score:4, Funny)

    by Anonymous Coward on Thursday May 27, 2004 @06:47PM (#9272337)
    I think we can now all breathe a huge sigh of relief as we know the dinosaurs did not, I repeat, did NOT suffer. We will all gain a few hours of sleep a night, I'm sure.
    • by Anonymous Coward

      PETA boycotts all asteroids in protest of the senseless murder of the dinosaurs.

      They are throwing red paint on meteorites, and showing up nude at natural history museums everywhere.
  • by superdude72 (322167) on Thursday May 27, 2004 @06:49PM (#9272349)
    All unprotected creatures were 'baked by the equivalent of a global oven set on broil.'"

    Thanks for the metaphor. This "heated air" concept is difficult to get across to the layperson.
  • conflicting theories (Score:5, Interesting)

    by pedantic bore (740196) on Thursday May 27, 2004 @06:50PM (#9272360)
    Just a few weeks ago, the theory surfaced that the asteroid impact was only a factor in the demise of the dinosaurs (the dust caused the earths temperature to drop just a few degrees for several years -- which is a big deal if you're a reptile, but not so much if you're a mammal). Now there's a new theory that says the dinosaurs were burned alive. Next week, there will be another theory.

    Personally, I'd like for these theories to go through a bit more critical review before they're broadcast to the public. This smacks as sensationalism more than science.

  • Great... (Score:5, Funny)

    by kaizenfury7 (322351) on Thursday May 27, 2004 @06:55PM (#9272398)
    So now we have prior art for animal crackers.
  • Nonsense (Score:3, Funny)

    by Ulumuri (550492) on Thursday May 27, 2004 @06:56PM (#9272402)
    Everyone knows that dinosaurs died during the Great Flood.

    Read the Bible!
  • COLD!!! not HOT (Score:3, Interesting)

    by insanely_mad (636449) on Thursday May 27, 2004 @07:18PM (#9272577)
    The really large asteroids can kick up up billions of tons of sulfur and other materials into the atmosphere. This can cause prolonged darkness for about half a year after the collision. The resulting darkness cause global temperatures to plunge near freezing. The COLD not the HEAT could result in large scale extinctions, including the dinosaurs
  • by Anthony (4077) <> on Thursday May 27, 2004 @07:30PM (#9272700) Homepage Journal

    Unfortunately the linked article is available in the Online Journal which you can either subscribe to or go to you neareast Uni Library and check it out.

    A Thermal heat pulse and the ejecta from the impact could travel around the world because of gravity dragging the ejecta back towards the earth. Upon reentry, the ejecta emitted IR radiation, brightening the sky globally. This means no night and no shadows (as the heat sources were distributed across the sky compared with the single-source solar IR radiation). This means there was nowhere to hide unless you were underground. Even rock crevices were no shelter. Subsequent fires igniting simultaenously [the suggest that there are isotopically uniform charcoal deposits at the boundary] would have added to the carnage. These fires were not significant compared to the intensity of the IR radiation. Normal solar flux ~1.4kW.m^-2, this event was calucated by Melosh in a previous paoer in 1990 to product ~10kW.m^-2. Note that ambient air temerature would have only rise ~10 K.

    As for survivors, those burrowers > 10cm below the soil surface would survive. Sheltering and semi-aquatic birds are posited to be survivors.

    The important thing is that this paper presents no specific fossil evidence. It does offer some phylogenetic evidence to support the bird survival hypothesis. It presents one model that can be further refined and/or refuted with evidence. It is not necessarily true or false but it can be falsified. They suggest checking Gondwanan sites for evidence of spherules (proof of ejecta reentering) and their distribution. That is the nature of science which the majority of posters thus far need to grasp. Think of science in terms of mathematical functions that approach a limit/converge as evidence and models accumulate.

  • The new study reviewed existing geologic evidence for the known impact and considered interesting patterns in species survival. How did some birds, mammals, crocodiles, snakes and other animals endure the calamity that wiped out larger species?

    That's a good question. But it's got a bug in it - the phrase "wiped out larger spieces". Better to say - selectively wiped out one branch of animals that came in all shapes and sizes, and lived in all kinds of environments right alongside animals that *didn't* die out.

    That asteroid sure was amazing!

    The survivors burrowed underground or were protected from the firestorm by swamps or oceans, says study leader Doug Robertson of the University of Colorado at Boulder. The details were published in the May-June issue of the Bulletin of the Geological Society of America.

    That's so plainly idiotic that it beggars belief. Dinosaurs came in a wide variety of sizes, some smaller than chickens. And there were many aquatic animals that also became extinct, that supposedly would have been safe according to this "study leader".

    Another win for the hypothesis that makes for a good special effect, then. And published by the Geological Society - well colour me not suprised.

  • Scientific studies have proven that if there was a nuclear holocaust, or a giant asteroid like the one that wiped out the dinosaurs, that the RIAA would continue to survive.
  • World-wide fire? (Score:4, Interesting)

    by Fizzol (598030) on Thursday May 27, 2004 @08:31PM (#9273176)
    According to the abstract fires would have begun wherever there was available fuel. Wouldn't there be a world-wide charcoal layer to go along with the Iridium layer if that were true?
  • by dummondwhu (225225) on Thursday May 27, 2004 @10:22PM (#9273883)
    Obviously, the dinosaurs were ignorant of the "Duck And Cover" method for surviving an incinerating holocaust. Or is that only for nukes?

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