Dinosaurs Died Within Hours of Asteroid Impact, says New Study 862
colonist writes "SPACE.com 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.'"
Re:Correct me if I'm wrong. (Score:5, Interesting)
Re:Broil? (Score:3, Interesting)
"'Twas brillig, and the slithy toves
Did gyre and gimbol in the wabe."
British [jabberwocky.com]? Broil is what you do at 4 o'clock in the afternoon [eosdev.com].
Re:Correct me if I'm wrong. (Score:5, Interesting)
Taken from: Wikipedia article on theory [wikipedia.org]:
So, proven for 99.9999% theory of gravity is still a theory.
The Truth is so much cooler than Fiction (Score:5, Interesting)
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)
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.
The important question... (Score:4, Interesting)
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).
Re:Obligatory Jurassic Park Quote (Score:4, Interesting)
What good would it of done, if they couldn't do anything about it? If we found a dinosaur-killer heading our way, could we stop it?
Re:The important question... (Score:1, Interesting)
So frankly, I wouldn't be surprised if lizard muscle was way stronger than mammal muscle.
Modoc
conflicting theories (Score:5, Interesting)
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.
Re:Detroy the world fallacy (Score:5, Interesting)
You're assuming that 9600 warheads detonated together would 'only' amount to 9600 times the results of one warhead detonation. This is by no means a widely accpeted view. It's much more likely that there is a "tipping point" where the damage from a nuclear exchange cascades into a catastrophe for the species (us).
In any event, I prefer not to prove it conclusively, Dr. Strangelove.
Re:Survival (Score:3, Interesting)
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 soil.
Of course, you wouldn't want to venture near any windows or skylights
Re:kill all the plants too (Score:5, Interesting)
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 space.com'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.)
Re:Correct me if I'm wrong. (Score:5, Interesting)
Unlike in some circles, well accepted means no has yet found evidence against it in science. Not, we all beleive it to be true. When someone has evidence against it, it becoem a disproved theory is the evidence is strong enough. However the theory of evolution has had no credible evidence against it, neither has gravity, or thermodynamics. Only small addendums.
I have faith in Christ. I need not refute scientific evidence to support my faith. God is wonderfull, sometime msyterious, and I needn't beleive in fairies ot beleive in God. Why should I beleive in creationist theories when the evolution theory fits my faith just fine.
Re:Broil? (Score:3, Interesting)
Gas Mark 9 for example was extremely hot, around 250 degrees C or more. Gas Mark 1 would be "warm up some buns" or something.
Re:Survival (Score:5, Interesting)
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.
Tor
Re:Temperature and sex ratio (Score:2, Interesting)
Plenty of evidence for this one. (Score:5, Interesting)
Another wild hypothesis without a shred of verifyable evidence.
I couldn't read it THIS time (because the server is slashdotted). But I did read it - or another describing the same theory - when it first became newsworthy some years ago.
There's plenty of evidence for it.
First off, the prediction comes straight out of physical modeling of what happens when a big asteroid hits:
- A bunch of rocks are kicked every which way.
- If the asteroid is big enough a LOT of them go into space.
- A fraction of them have enough energy to get above the atmosphere but not achieve escape velocity.
Once you realize those three things, it's straightforward for a physicist to calculate, for various size impacts on various sites (land, shallow ocean, deep ocean), how MUCH mass goes up, how MUCH of it comes back down, WHERE it comes down, HOW FAST it comes down, and what the results are.
So they calculated that. And came to the conclusion that for impacts of a certain range of sizes the result would be several hours of a rain of sand, all over the Earth, at speeds of up to several miles per second (plus rains of rocks of varying density at different distances from the crater and its antipode). The sky becomes essentially solid meteor trails for hours.
And those are HOT! Hot enough to dry out most of the plants and set them afire. Hot enough to kill any animal life on the surface that can't get underground or under water right away and then stay there for hours.
So if the sky turned into a broiler oven over the whole Earth for several hours all at once, what does this predict? One hemisphere is day and the burrowing nocturnals survive, the other is night and the burrowing diurnals survive. (And in particular regions it got REALLY hot, or REALLY shocked by the primary impact or the secondary rain of rocks, and NOTHING survived).
So they looked at the fossil record and that's what they found. Prediction confirmed - very good evidence for the model. Further, they could now tell WHAT TIME OF DAY the impact occurred and roughly where.
Then they looked in the area where this model predicted the impact should have been and FOUND A CRATER of the correct size (along with plenty of other evidence that this PARTICULAR crater's impact coincided with the extinction event).
Looks solid to me. Unless something new comes up I consider the puzzle of the extinction events solved.
The only question I have is: Why is this news NOW?
Re:Interstellar catastrophic source no longer need (Score:1, Interesting)
That's a lot of nonsense. There is no comparison to a whopping big asteroid hitting the planet, even as a simple matter of the total energy equivalence. Its like saying that a liter of botulinum toxin can kill the entire race. Technically it might be true (I don't really know), but in practice you can't come remotely close to killing the entire human race even if you had the toxin and nobody stopped you from using it.
If the US used its entire nuclear arsenal with the specific intent to maximize the body count, they still would probably not be able to kill more than one billion at best. Do the math. You have to kill 100,000 people per nuke for every single nuke, and even that will only get you the first billion. And in practice, there are only a relatively small number of targets that will net you that many kills if you nuke them.
Nukes are very destructive, but most people have a conception of their destructive potential that is totally out of proportion to what they are actually capable of. We have enough nukes to scorch a good bit of earth, but not even remotely enough to do a planet kill or even make more than a minor dent in the total human population.
Re:The important question... (Score:4, Interesting)
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.
COLD!!! not HOT (Score:3, Interesting)
Re:The important question... (Score:2, Interesting)
This was disproved quite some time ago. The fact is that the mass of the water that would be displaced by an animal as large as a sauropod would prevent it from breathing.
Along these lines, you know a giraffe has valves in its neck to prevent blood flowing to its brain too fast? All evidence suggests that the brontosaurus and other similiar behemoths lacked these valves - so if they lifted their heads too fast, they'd at the
Ref, please. AFAIK, there has not been one single recorded instance of a sauropod being discovered with fossilized arteries and veins present to make a claim either way.
Stupid theory (Score:1, Interesting)
Is it possible to recreate all the birds and reptiles from nothing in such a little time by evolution?
Craters from Down Under (Score:2, Interesting)
Re:The important question... (Score:5, Interesting)
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.
Re:The important question... (Score:1, Interesting)
Re:Survival (Score:2, Interesting)
Weapons are only good if your willing and have the time to use them. If I bring caned food over and we all start eating... then bam!!! Dead hosts... turned into a supply of meat.
You gota rember not everyone's mind conforms to the standard model. there are reasons we have perverts and psyco's... the trait's are good for survival of the species in 'primal' settings. We are animals after all... Civilation falls, and only the strong survive.
Re:The Cock Roach (Score:3, Interesting)
Don't laugh. You know what a wood louse or sow bug is?
Well, they have larger underwater cousins [noaa.gov], which are sometimes called "sea roaches".
You can see them live at the New England Aquarium [neaq.org].
Re:The important question... (Score:3, Interesting)
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?
Questions like these make me discount a climatic-event hypothesis. Sure, it may have been enough to kill off a lot of dinosaurs, but not all of them. Instead, I want to suspect that perhaps, biologically or genetically, there was something inferior about dinosaur physiology -- something so deeply embedded that even deviations away from the norm weren't enough to adapt to a new environment.
On my tinfoil-hat days, I start thinking about how we might want to look closer at everything we classify as 'reptile' and make sure we aren't mistaken.
Re:Plenty of evidence for this one. (Score:5, Interesting)
I presume you mean "extinction event", not "events". There have been a few mass extinctions, not all caused by impacts.
Anyway, there's a lot of evidence to indicate that something probably hit the Earth, yes. The puzzle that remains is why it only affected the dinosaurs.
Remember, they were all sizes and lived in all kinds of environments, so saying things like "the smaller animals did such-and-such" also includes the smaller dinosaurs. We don't have any small dinosaurs running around today (or even large ones - assuming that they would have kept their capacity for diversifiation and speciation if even some had survived) so there was obviously more to it than "something big hit the Earth".
That is the remaining puzzle - and nobody has been able to even come close to solving it that I've heard. I'd be interested to hear of anyone who has, though!
World-wide fire? (Score:4, Interesting)
Re:Broil? (Score:3, Interesting)
Broiling is what the English call grilling.
Of course a grill over here is one of those outdoor things with charcoal (or gas).
Re:Correct me if I'm wrong. (Score:3, Interesting)
Because the burden of proof was on them to prove that it fits the observed Universe. If it's a theory, it's already done that.
I mean, if we're going to play that game, then I have a theory that you're an idiot.
That's not a theory. It's a hypothesis. The next step would be to devise experiments to prove or disprove the hypothesis. If the experiments all prove valid, then the hypothesis becomes a theory. It's not a theory until it already has backing.
Once it's a theory, then it becomes a valid explanation for the way the world works. After this, of course people will still attempt to confirm it, but they can also use it to attempt to explain new things, because all the evidence that backs the original theory backs any new ones.
A "hypothesis" is an unvalidated assertion - a conjecture. A "theory" is a validated assertion - a conjecture that has a body of data behind it which would need to be explained equally well by any hypothesis competing with it.
I don't know when "theory" became synonymous with "hypothesis" in everyday speak. It isn't. A theory is disprovable, but with far more effort than a hypothesis. In order to disprove a theory, you need to either show the evidence was bad, or the theory was incomplete.
Taking the case of evolution, there's well more than enough evidence that the first suggestion isn't possible - the evidence is good. At this point, the only solution for evolution being wrong is if it's incomplete, akin to, for instance, Newton's Theory of Gravity.
Not bloody likely. (Score:1, Interesting)
Besides, the dinosaurs didn't die out all at once; extinction took at least 100,000 years (a fact generally ignored by the catastrophists).
Re:Detroy the world fallacy (Score:3, Interesting)
The whole problem is that people are vague about what they mean when they say 'destroy the world.' A full-scale nuclear war would definitely
- kill vast numbers of people immediately in the cities of the countries that fought
- kill vast numbers of people everywhere else in those countries, because there wouldn't be trucks driving into town to deliver groceries to the supermarket.
It might also trigger a nuclear winter, in which so much dust and smoke goes into the atmosphere that it blots out the sun for years. A nuclear winter, if it occurred worldwide, would kill almost all humans, even in places like Tasmania and Tierra del Fuego, because it would eliminate all agriculture. It would also, of course, kill off an awful lot of species. Last I heard, the nuclear winter hypothesis was not something that could be proved 100%, but it's not something you want to try in order to find out.So it all depends on whether you consider it as 'destroying the world' if the war kills you, kills everybody you know, destroys civilization, and puts our species back to a tiny population of stone-age tribes.
I believe a big asteroid strike is also hypothesized to be able to cause a nuclear winter, so it may be that there was a one-two punch: first a lot of species got killed off by the heating, and then a lot more got killed off by the nuclear winter.
Re:Correct me if I'm wrong. (Score:1, Interesting)
They don't realize that very the idea the world can be explained rationally is itself just as much as matter of faith as biblical literalism. Irrational explanations are met with ridicule and disbelief because non believers can't accept that the world might just run on the whim of omnipotent irrational deities rather than on the rational clockwork posited by modern physics.
Re:Correct me if I'm wrong. (Score:2, Interesting)
This instant death thing is one possible change. Another more widely expected modification is that the extinction occur over a long time and involved a number of rocks. In addition, the exact changes that occurred are under continuos investigation. Many lay people focus on the sound bites, while missing the details that really are the most interesting aspect of any science.
One of the most interesting theory to me is that of electricity running through wire. Now the theory states that a potential difference causes the electrons to move and thus create a current. The current can be used to power things. This seems to be pretty much established. I know few people that would postulate electricity is caused by an aether that man can never characterize. But when I was in school the professors talked a lot about whether the current moves through the wires, as would be normally assumed, or travel in a cloud around the wire. It is an interesting point. Either solution may imply other details in the theory, but no one is going to think that current is anything other than electrons.
Re:Pet Theory (Score:1, Interesting)
It's interesting that the weak inherit the earth. Us being at the top of the food-chain isn't very encouraging. So we must kill all the weak things before it is too late!!!
Re:The important question... (Score:3, Interesting)
Tinfoil-hat wearers are generally mammalian, tho one could make a case that some might in fact be cold-blooded reptiles.
Re:Detroy the world fallacy (Score:2, Interesting)
Re:Plenty of evidence for this one. (Score:1, Interesting)
In summary: a computer model (which might not represent reality) of certain classes of impact might, feasibly, result in mass extinctions. That's all you have.
However, that's not evidence. We have large craters that are not associated with mass extinctions, so we know that they don't always result in global catastrophes. We also have a fossil record that shows the dinosaurs died out over an extended period of time, not all at once. Plus, plenty of animals didn't die out, and many of them are short-lived and fragile.
There are also competing theories that are just as plausible as the asteroid collision theory. (For a good time, google 'deccan traps'.)
I wouldn't sign off on this one just yet.
Re:Broil? (Score:1, Interesting)
What do the brits call that outdoor thing?
Then how do we have birds? (Score:3, Interesting)
Re:Detroy the world fallacy (Score:1, Interesting)
The truth is, they were not really afraid of their 100MT bomb... What they did realise that the destructive difference vs cost of making a 100MT vs 20MT bomb was that they could cause more distruction with 5 20MT bombs than a single 100MY bomb, with the 20MT bombs costing only 40% of what the single 100MT bomb cost.
With all this talk going around about a heat wave, the limitation of what heat could be dispersed, and the range that would actually go, even with that much energy is quite limited. The honest reality is that type of blast, being one that would create a 200km crater, would probably only extend somewhere between 2500 and 4000km from the impact. Even less if that heat wave traveled over a body of water. Not only would the turbulance caused by the flash evaporation of the surface of the water would in some ways create a bubble that would only let the heat outside be the boiling point of water once it reached a point of enough water vapor being in the air to contain it.
Now, here is what killed everything... When something like this happens, you basically are dealing with conflagrations on a unseen scale. in the case of an fission reaction, you're dealing with the effects from a pulse of heat, and the heat thats being created from things burning because of this. In a fusion situation, you're dealing with a micro sun, meaning that you're dealing with a sustained output of heat until the fuel of the bomb is consumed, although it tends to be very short, but if you measure it, it doesnt spike and then start to go down slowly, it actually builds up. Comparing an asteroid impact follows the fission heat model with some twists Those twists being molten material being flung all over the place, creating their own conflagrations unless the material landed in water, or a dune type desert that lacked vegetation. All these fires do raise the temperature, but they do some other things as well, and much more immediate... They raise the CO level in the air to a poisonous level that would basically choke everything out that relied on air. Now, sea creatures that rely on air probably got a reprieve because of the natural oxegenation processes that take place in the ocean..
oh welll enough babble.. time to sleep...
Re:Broil? (Score:1, Interesting)
I was quite surprised when my U.S-native wife took me out for some Barbeque. Not quite what I was expecting.
Re:Broil? (Score:2, Interesting)
I'm forever amazed at how we're devided by our common language - right up until I talk to someone from another bit of England.