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New Evidence About 'The Great Dying' 250 Million Years Ago
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.
New clues to 2bn-year-old murder /. habit of not bothering to RTFA.
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
/. If the government wants us to respect the law, it should set a better example.
Mmmm... unprocessed gasoline...
Life is the leading cause of death in America.
They found the weapons of mass destruction!
Random rants about technology: http://technorants.blogspot.com
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.
not "first evidence"...
just like in judicial cases you can have circumstantial evidence, scientific hypotheses can be supported by indirect evidence.
I knew I should not have put that giant can of Lysol in the time machine. But I did it anyway. Sorry.
Don't blame Durga. I voted for Centauri.
There wouldn't have been much on land at 2Ga.
there can be hundreds of pieces of indirect evidence and logical arguments supporting a meteor hit.
this is the first direct evidence i.e. they found the meteor (or what's left of it).
I'd say that if everything points to a meteor, and then you find the actual meteor, then that's as far from "sketchy" as possible and has very little to do with "belief".
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.
If Jesus wants me it knows where to find me.
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.
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.
The BBC have a much better version of the same story with addition information and some on the opposing view points BBC.co.uk
Look at it another way: this just means that 80% of terrestrial life and 95% of marine life are completely useless.
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.
stuff
In the case of the giant meteor coming to earth I think they tend to call it "insourcing". But it's all terminology of course. In the end, it's all because of foreigners!
Daniel
Carpe Diem
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
The article tells us that the event happened 250 million years ago.
It's always good to rtfa..
:^)
perl -e 'printf("%x!\n",49153)'
You know, there hasn't just been one great extinction in history. The dino-killer happened 65MYA. This article is talking about a much earlier event that happened 250MYA.
The comment in the article about the Chix . . . Chick . . . Mexican event refers to the idea that impact catastrophies may not have been the isolated event many assumed. Considering the large number of impact structures of up to several hundred kilometers in diameter around the world, it seems pretty obvious to me that it would have had a large effect on the development of life.
Most of these structures are so weathered that they aren't recognizable from the ground. For instance, the Chesapeake Bay on the east coast of the United States is a 90 km impact structure. Here are a couple of links about terrestrial impact structures. The second one is the best.
Years ago, when Mariner 10 went and disovered the Caloris Basin and wierd terrain on Mercury, 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 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.
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.
Trying to use sarcasm in text-based forums does not work.
You're not "supposed to" believe it, where did you get that idea? Clearly you have no idea how science functions, why don't you learn what science is before publicly criticizing it? It is obvious from your post that you don't even understand the basics of the scientific method, despite the fact that you think you "know a bit" about science.
If you actually read up a bit about this, the scientists here are basically saying that this MIGHT BE a possible cause of one of the great extinctions (read "more research required"). Furthermore, this is now just one new "HYPOTHESIS" against two other major "HYPOTHESES" that alread exist that proposing other "POSSIBLE" reasons for this great extinction.
Certainly nobody has asked you to "believe" any of these possible explanations, and none of the scientists involved have claimed that their hypotheses are 'the truth' either. In fact, with things like this, scientists never really decide that any one theory is "the truth" - they basically often settle on a theory that is "the most likely" - they, however, ALWAYS "leave the door open" to other possible explanations that may appear in future that are better. Always. (This is all in refreshing contrast to religions like Christianity, where you are in fact expected to 100% completely believe something regardless of whether or not there is really evidence for it.)
The slashdot blurb has also spun this thing completely wrong. So even worse, now you make decisions about scientific theories based on a slashdot blurb. Sheesh.
You're confusing the "great dying" of 250m years ago with the extinction of the dinosaurs 65m years ago. The Yucatan meteor has long been used as a possible explanation of the latter. This new crater off the coast of Australia is now seen as a possible explanation of the former.
How on Earth you arrive at that conclusion? The big extinction didn't kill everything or wind speciation back to step 1. The meteor didn't kill off 80% of species and then magically devolve the remaining 20%.
Ultimately, I think, it comes down to faith.
No, no it does not. These scientific theories really do work, as you witness every day when you use a computer or a TV set or a DVD player. Whether scientists are right about, say, the speed of light or radioactivity does not need to be taken on faith.
Remember, creationists aren't just disputing some evolutionary biologists somewhere. They have to dispute physics, geology, cosmology, basically anything that gives you a dating method or shows what the place was like billions of years ago. Just about every branch of science eventually matures to the point that it burps out evidence the Earth or universe is old.
X
Now, instead of four billion years, they've got to explain in it 250 million years. Given that they've already posited that mankind's ancestors appeared about 50 million years ago, they're down to a mere 200 million years to go from single-celled to upright and walking.
Wrong, wrong, wrong. The meteor killed 80% of life, not species. I'm sure there were small animals left, something like insects (that's multicelled), maybe also other small animals like lizzards that live in caves that were able to adapt. Even though most life was killed, I'm sure a lot of species survived.
And even if that wasn't true, and all multicellular life were wiped out, evolution is STILL a better theory than "The invisible man in the sky made it all with magic". That's just silly, and is a fairytale best reserved for kids.
Everything seemed to be going so nice
'till the end of all beings punched right through the ice
You are using "old-school" ideas of abiogenesis to back yourself up. In fact, it is not very hard for organic compounds to self-organize into the needed components of life. Take for instance the cell membrane, this is a sphere of phospholipids. If one just takes phospholipids and adds them in water, they self-organize into a sphere and provide a membrane.
You may ask where these organic compounds came from, well a classic experiment (earned the researcher a Nobel prize I think) called the Miller-Urey experiment showed that if one simulated the conditions on a primordial earth, one got organic compounds (ranging from your simple alkanes to the building blocks of protiens, amino acids) were formed. And these processes happen relatively quickly, thus I do not see the evolution of life as being improbable.
If any of my facts are wrong please correct, if you want back-up for my statements, feel free to request it.
What crap. Stop trolling. The evidence in science is based on pre-observed behaviour and hypothesis.
And they are just collecting evidence to substantiate their hypothesis.
Religious claims cannot be recreated. A scientific claim can.
Tomorrow if this is disproved, you can throw this out of the window. I'm yet to see any religious figurehead materialize before me -- that still hasn't made any religious believers throw out religion.
Science is based on assumptions, which evolve into hypothesis and are substantiated with evidence. Plain and simple. When another kind of evidence is found, science simply changes it's assumptions and hypothesis to fit the facts.
Besides, whether or not you believe it is entirely upto you. Your soul is not going to hell if you don't. It's just the most plausible thing that might have happened, and in the light of no other explanations, this seems just about right.
And look at the choice of words from the article -- they think, they believe etc. -- they do not say, we are so damn sure that THIS happened.
Have you been to the sun? How do you know it's full of Hydrogen and Helium? It's based on an assumption, that was later on substantiated with evidence (spectra of the sunlight). Have you seen a Black Hole? It was based on an assumption that it's quite likely Black hole exist, and later on they were substantiated with evidence by observation.
This is no different.
Religion merely makes claims, and has no need to substantiate nor prove. Unlike science.
And judging by your comments you know nothing of science.
Empirical claims are probabilistic. All empirical knowledge depends on the persistence of objects (and behaviors, really) in time; i.e., we acknowledge that gravity exists because it is repeatable over a sufficient number of tests for us to draw the conclusion that it will continue to be repeatable into the forseeable future. We really don't have any *reason* to believe that this is the case other than statistical analysis - "It's always been this way."
Thinking outside my Head