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.'"
Correct me if I'm wrong. (Score:1, Insightful)
We're getting kind of thin here.
Re:Correct me if I'm wrong. (Score:5, Insightful)
All the dinosaurs? (Score:2, Insightful)
If this is true wouldn't there be a large carbon layer evenly distributed over the earth's surface from that time?
Facts? (Score:4, Insightful)
"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 http://www.msnbc.msn.com/id/4969840/ for a similar story.)
so what is the consensus *really*, in the scientific community? or is there just none?
Re:Correct me if I'm wrong. (Score:3, Insightful)
Now we can go looking for X and if we find it and the prediction was somewhat unexpected before the theory was proposed it is a strong indication of its validity.
Case in points Einsteins prediction of light being bend by high gravity object that was indeed confirmed.
Same here if we do find a a lot of different Dinosaurs in the same narrow strada around the world it make the theory more likely.
Re:Temperature and sex ratio (Score:0, Insightful)
sounds like a neat little theory
kill all the plants too (Score:5, Insightful)
Detroy the world fallacy (Score:5, Insightful)
This one I hear a lot. First of all, despite what you may have heard, really the majority of the energy of a nuclear explosion turns into heat and blast immediately, NOT radiation. The only exception to this is the so-called Neutron bomb, designed specifically with radiation (more specifically fast neutrons and gamma rays) in mind. But realistically, although the Americans have built approximately 70,000 warheads of almost 70 different types, they now possess a stockpile of around 9600 warheads. Surprising as it may sound, this is NOT enough to 'destroy' the world. Even hitting every city in the world with everything in every country's arsenal would not be able to 'destroy' the world. The world is still a
BIG place. Keep in mind the Russians have around the same numbers of warheads.
Re:You know, thats really not funny. [NT] (Score:5, Insightful)
I tend to personalize it a bit: "If you believe that ___* is 'just a theory,' be aware that gravity is 'just a theory' as well. I invite you to try jumping off a skyscraper because, surely, nothing that is 'just a theory' can hurt you."
*___ is almost always evolution, of course, though sometimes it's relativity.
Re:kill all the plants too (Score:5, Insightful)
Sorry, but this theory doesn't even sound plausible. What could they base it on? (Sorry, article
Why isnt this article SPAM (Score:5, Insightful)
To be honest, I have no idea why an article like this is not considered spam, if we have to pay to read it.
Why is that sad? (Score:4, Insightful)
The fact that man has the power to potentially do something shouldn't make you sad. It should actually make you proud. Now, if man would actually do it, that would be sad.
Man can kill man, but until they do, there is nothing to be sad about.
Re:The important question... (Score:4, Insightful)
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.
Re:kill all the plants too (Score:2, Insightful)
Re:You know, thats really not funny. [NT] (Score:2, Insightful)
The theory of gravity would be something like F ~ m_1*m_2/R^2.
Re:Correct me if I'm wrong. (Score:4, Insightful)
Before and after Chicxulub Earth was experiencing a lot of volcanic activity. So much in fact, that the compositiom of the atmosphere was changing. As I recall the oxygen content was reducing from 30% down to 24% (I'm sure these are not the exact numbers, but they are close). Less oxygen meant that animals had to work harder in take in the same amount of oxygen. The dinos may have have suffocated.
Of course, a large impact would not have helped them out...
Re:You know, thats really not funny. [NT] (Score:5, Insightful)
Re:You know, thats really not funny. [NT] (Score:3, Insightful)
Actually, the fact that you fall if you jump off a skyscraper is the fact of gravity.
You are assuming that you know what will happen in some unobserved (hypothetical) event. Either you are Psychic, or you are using some theory that seems to have been useful in the past to predict what will happen in the situation you propose.
Whaddayaknow? You were using the theory of gravity. (the fact of gravity that you speak of is strictly for chumps)
Re:The important question... (Score:2, Insightful)
Oh... that's why whales are extinct.
Re:kill all the plants too (Score:5, Insightful)
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.
m-
Re:Why is that sad? (Score:3, Insightful)
- "Hey, we managed to coexist for 40 years without incinerating 500 million people, this calls for a celebration and a congratulatory pat on the back. Attaboy!"
??
Re:Correct me if I'm wrong. (Score:3, Insightful)
Obligatory Jurassic Park Quote is Luddite Crap (Score:3, Insightful)
So you only "earn" the "right" to make a product if you personally developed every single scientific theory and technological breakthrough necessary to construct it, working from first principles you personally developed?
Reminds me of how "The New Math" created a generation of ilnumerates by (instead of teaching counting and arithmetic skills) requiring them to invent for themselves the entirety of several millenia of number theory behind arithmetic and mathematics - while being distracted by "helpful" information about multiple bases and the like.
You stood on the shoulders of geniuses to accomplish something as fast as you could and before you even knew it you had it.
It was a GIANT who characterized his own scientific breakthroughs as being able to see farther than others because he stood on the shoulders of (previous) giants.
Following the Ian Malcom character's advice leads to abandoning, not just genetic engineering, but all of science, history, engineering, industrial society, archetecture, farming, hut-building, and even stone knife making. Humanity would be reduced, not just to the level of hunter-gatherers, but to the level of purely instinct-driven animals (below primates, cats, birds, and even some reptiles).
= = = =
None of which in any way detracts from your point, which was dead on. B-)
Re:Correct me if I'm wrong. (Score:3, Insightful)
No offence, but my wife was declaired dead for almost two minutes about 5 years ago. What did she see? Nothin'. She thought she had simply fallen asleep. The one thing she does remember is that her chest hurt like hell from the electrodes though.
Granted, she's only one data point, and I'm sure you will discount her experience. But I thought I'd share it anyway.
Re:Correct me if I'm wrong. (Score:3, Insightful)
Cool. An anonymous coward knows more than the Pope about religion. Arrogant, aren't we?
The Pope stated sometime in the 1980s that christianity and evolution don't contradict, and that one can easily believe in both.
Or you can read the very well written commentary here [newsday.com], and get a clue. Using the same stubborn-headed aspect that you bedevil in others makes you just as bad.
Re:But so much survived (Score:2, Insightful)
So the mammals could survive. Reptiles are cold blooded and like insects don't need a lot of food. And perhaps only the smaller once survived and they grew that what you are used now. As Elephants used to be little rat like creatures once.
But what about birds? I think because they could fly (move fast from one area to another), were small and like dino's were hot blooded. They survived.
I saw once this docu that actually the age we are in now can be called the age of the birds. As they are everywhere even in cities were only humans and rats can survive.
Re:You know, thats really not funny. [NT] (Score:1, Insightful)
So, we've given up on real science then? (Score:5, Insightful)
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.
Re:You know, thats really not funny. [NT] (Score:3, Insightful)
Oh, and just so you know, the theory of gravity hasn't been proven, either. It's just got lots of evidence for it, as does evolution. Theories can only really be disproven, not proven.
wrong side of the planet (Score:4, Insightful)
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.
Re:Correct me if I'm wrong. (Score:4, Insightful)
The AC says:
The AC, is in fact, quite mistaken. What he quoted here is not the core tenet of Christianity; this is just a nice way to live with God thrown in for good measure. What Christianity is is this:
God and mankind had a good releationship, but this relationship was broken because people choose to live without acknowledging God. People are incapable of reconciling this relationship, so God, because He loves people, sent His son Jesus Christ to die on the cross and suffer horribly as a reconciliation so we can have a restored relationship with God. The restored relationship with God is what allows people to actually succeed in loving others and God...
That is the core of Christianity; not the Pope, not communion, not hymns, not going to church every week, not even the Bible. You can verify this for yourself, it's not some "theory" about Christianity - you should be quite able to go pick up a Bible and read it and you should see this is the case, and if you are so inclined, I'd recommend it.
As a man who has decided to commit himself to Christ, I kind of am distressed and saddened by the fact that people do not really understand my faith and lump it in with "you narrow-minded American Christian!". Especially since I am a scientist, love physics, and don't see a conflict between evolution and a universe created by God (if God is all powerful, why can't He use evolution?)
Anyway, at least I hope that you have an understanding now that the common perceptions of "Christianity" might not be universally accurate. Another instance of "don't believe everything you see on TV! (or read on /.!)"
Re:Correct me if I'm wrong. (Score:2, Insightful)
I'm a Christian and I'm fully ready to believe in evolution--and I don't entirely discard it. But something just doesn't make sense there, and it's not the religious angle that causes me grief.
Re:substantial with a lot of holes (Score:3, Insightful)
Now true, tuataras are burrowing animals, but they have to leave their burrows to feed on the insects they love so much.
Don't even get me started on birds. This theory has so many holes in it. If the Earth was grilled as the report suggest, then where's the geological evidence? A thin layer of carbon circa 65 million years ago representing all the burnt land flora?
Even the author admits it doesn't account for the mass extiniction that also took place in the ocean.
So what do we have? A theory that has no direct evidence to support it, has huge holes, does not fit with the observed evidence we've been collecting for the past two hundred years, and is incomplete according to the author. Nice one.
Re:But so much survived (Score:3, Insightful)
Exactly! Evolution put a lot of effort (so to speak) into evolving seeds that refuse to germinate unless the conditions are just right. Germinating only when conditions are right maximises the chance of survival for the plant.
I had a packet of cactus seeds with instructions to soak them in very hot water for one minute, plant them immediately afterwards in moist sandy soil and leave them in the dark for a week or so. Even so, mine didn't germinate until three weeks later. Fussy little buggers they are.
Re:Broil? (Score:2, Insightful)
Which, of course, produces a meal just as flavorful as your average British meal!
Point of fact-- broil goes back to Middle English [m-w.com], which, as far as I know, was never spoken in America.
And the chicken-sized dinosaurs still exist... (Score:3, Insightful)
The extinction event killed off all species larger than about 20kg. That wouldn't have included any mammals. Mammals 65 million years ago were tiny (mice sized) and most likely nocturnal.
Re:Correct me if I'm wrong. (Score:2, Insightful)
Hell, the timeline for the Book of Genesis and the big bang theory more or less coinside, just the scales are different.
Oh, and I'm sure I'll end up believing in something after I die. It's just what that's the problem. Most of my Hindu friends think this talk of heaven and hell is quite funny... "if at first you don't succede..."
Re:thats really not funny. /I'll bite [T] (Score:3, Insightful)
One of the problems some people have with the Darwinian theory, is it is too often presented as "All selection is natural selection" or "Natural selection is sufficient to account for all observed variation", which is precisely what you yourself just offered a fine counter-example to. Proof of natural selection would be better based on those wolves you bring up towards the end, but the evidence there is in the line that extends backwards in time from the modern wolf to the varois proto wolves, rather than the branches off that line that make up domestic dogs.
Re:Anipodal effects (Score:3, Insightful)
Debris concentrations would have a circular modified to oval distribution around and to the west of the impact crater that would somewhat resemble an interference pattern. There would be no antipodal concentration because most of the really high energy debris is thrown almost straight up, not to the much more acute angle to the Earth's surface that would result in the concentrations you describe. Actually it's likely that little debris would reach the antipode, as debris that was that energetic would either go into a highly elliptical orbit (randomizing the fall distribution) or escape Earth entirely (as the first article notes)
However, the shockwaves that would travel along the Earth's surface would experience peak(s) at or near the antipode; not anywhere near as much of one as would happen on, say, Mercury (which is more near a perfect sphere and doesn't have anywhere the variations in surface/mantle density that the Earth does). This phenomena has been theorized to have resulted in some formations on Mercury -and to a lesser extent, the Moon - but those formations have nothing to do with debris distribution, rather shockwave intensity peaks). To what extent shockwave concentration at the antipode would occur on Earth is yet unknown - it's bloody difficult to model.
I could probably find all kinds of links to support what I'm saying here, but it would take a lot more time than I have right now. I'd suggest doing some further reading; there are some really good books/articles/papers out there on the subject - if you can handle the math, which is tortuous.
In any case what I posted is still pretty much a simplification...
I'm not posting this to flame you, but you are visualizing it wrong. Trust me - I've studied this stuff both in school and as a hobby for nearly a quarter century. Guess I just hate seeing an obviously smart and imaginative person misreading something
Cheers,
SB
Re:Anipodal effects (Score:3, Insightful)
Yes, I saw those quotes. But those are statements by third parties, not support per se. There are better links, like this one [arizona.edu] for support purposes (and see below )
That said, I have some problems with Melosh (and Kring/Durda)'s models. For one thing (as can be clearly seen in the gif on the link I provided) they postulated wildfires from impact debris in an area that at the time included very little land; and we have no way of verifying the computer model that they used for impact debris distribution from geological data.
Hence, my reaction to it; and sorry, I didn't mean to berate the messenger.
In any case, I've read about Melosh's work before, and I find the mathematical models he used somewhat suspect - but I'll withhold further judgement on that until I can obtain a copy of his paper (which a friend of mine is mailing me this week, got interested enough to request it rather than reading the thirdparty-etc abstracts.) Like I said, the math is tortuous; and a lot of the effects of those impact energies are not as well understood as we'd like.
I am not saying that it won't All I am saying is that debris will fall at the antipode in a grearter concentration than other distant locales. Are you saying that none of it will reach the anitpode? Are you also saying that none will reach orbit?
Um, no to either question. As to whether debris in an earth impact would have a concentration at the antipode is still pretty much conjecture backed by a couple of computer models. Personally, I disagree with it; at least I don't think (not having seen his paper yet I can't make a stronger case than that) that he's modeled all the factors correctly, such as impact obliquity, high-altitude wind factors, gravitational variations effecting debris suborbit trajectory, suborbital atmospheric variations, etc, blah blah blah
Of *course* some of it will reach the antipode. Whether there is a relevant concentration there is what I debate; it's not proven to my satisfaction, not yet, anyway. Orbital mechanics postulates that a portion of the debris may land there, but I think I've already dealt with that.
As to whether it will reach orbit, it's pretty easy to show that a fair amount (10% or so according to the models) will not only reach orbit but be ejected from the Earth-Moon system entirely (and that 10% figure of course depends a great deal on the impact obliquity and whether or not it impacts deep water or land, and also on the impact energies - a 10-20 km body is borderline in that respect, additionally, impact velocity is a lot more important; KE=mv^2, and we don't have *any* even semisolid figures as to either.)
I guess what got me about your post was that you linked to a couple of sites that merely mentioned the antipodal debris effect, and not to one that was from the horse's mouth, so to speak.
The reason I talked about the shockwave effect a lot is because extremely good evidence for it has been found on other planets (and possibly even here, the Permian event and the Deccan trap eruptions are a good example), and I feel that shockwave concentration in the K-T event probably accounts for a lot more geophysical effects than debris concentration - and yes, I'm aware that some circumstantial evidence has been found for debris concentration effects on the moon [google.com.ni] (fascinating reading in itself, scroll about halfway down), but impact debris distribution on the earth is going to be entirely different than it will be on a smaller body with no atmosphere.
It was also late, and I was tired, and probably not thinking clearly
Anyway, having googled it a bit, I'd sugges