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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.
About the most advanced lifeforms at that time were bacteria ... I wouldn't call it a great dying
Looking for any old 8-bit Heathkit/Zenith software/hardware - http://heathkit.garlanger.com
There wouldn't have been much on land at 2Ga.
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.
The BBC have a much better version of the same story with addition information and some on the opposing view points BBC.co.uk
Ben
cheers, ben
Never miss a good chance to shut up -- Will Rogers
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
Scientists believe they are on the track of the biggest mass murderer in the two-billion year history of life.
Um, if you RTFA, it never says that the murder is 2bn years old. It states the the history of life is 2bn years old.
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
I wouldn't trust something written by a guy called PornMaster....
I'd throw out that while whatever we have today evolved from the 5-20% that survived the Permian extinction, what we have today probably evolved from less than 1% of what was around right after the Cambrian explosion.
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.
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.
No, they cannot measure how many individuals existed at any given moment from the fossil record. Counting fossils only give you an indication of how many were preserved, and some clue as to relative abundances for the more common specimens.
They can measure number of species quite easily, just by counting the different species in the fossil record. There are problems with deciding whether 2 similar animals are different species, and the data can be skewed by the fact that soft bodied animals may not preserve as well as boned and hard shelled creatures. But the species count is far more accurate than the count of individuals.
**TODO** Steal someone elses sig.
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.
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.
I posted earlier that I had heard this on NPR, when they were discussing it they didn't say that the meteor was the whole cause of the die off, they believe that when the meteor impacted (in the ocean incidentally which may explain the lack of ejecta you speak of, though it seems unlikely) that the impact sent a shockwave in the core, causing siesmic and volcanic activity on the other side, which would be the main cause of the die off. Now I don't claim to know everything, I'm just quoting what I can remember, so if you can tell me a little more about why that would not be possible then I would be more inclined to believe that it was only volcanic activity. But the theory and it is just that, as all things speaking of events 250mm years ago, seems reasonable enough to me. Cause and effect my good man.
-RevSin
What really gets me is that none of the so called "scientific" origin-of-life theories are logically sound. Nor are they scientific, in the truest sense of the word - their hypotheses cannot be tested.
Of course they can be tested. You can make a hypothesis about how cells form and you can go look for such cells in the fossil record. You can create evolving DNA and RNA strands in a test tube. You can make artificial life forms in the laboratory (this is in progress). There are many clear, simple and easy-to-understand ideas about how life can get started.
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.
No. The extinction killed off most species, but certainly did not reduce life to single cells. Left behind were complex plants, fish, reptiles. Its all there, clearly recorded in the fossil record.
Rather, science often illumines our knowledge of God - we discover the perfection of the Creator in witnessing the beauty of the created.
Apart from the aspects of the 'created' you refuse to look at. Surely its up to God (assuming he exists) to decide how life is created, and unless he is a huge practical joker and trying to fool us, there is overwhelming evidence that evolution is the method.
Thank you! I was about to write something critical of the semi-Kantian analytic/empirical dualism. The idea that some knowledge is "inherent" is absurd. Yes, some definitions lead to other conclusions, but at some point those definitions rest on sensory input of some form. At root everything is in some way abstracted from empirical data. "Three" does not exist but for the experience that objects of some kind exist. Without the concept of differentiating between objects of some sort enumeration is not possible. (The one dimensional universe in Flatland is a fair example of how an undifferentiated space would not allow enumeration. Everything is part of the single inhabitant. Perhaps he could conceive of "one, but "zero" and "two" have no meaning if he fills all available space.)
Boys from the City. Not yet caught by the Whirlwind of Progress. Feed soda pop to the thirsty pigs.
For your dining and dancing pleasure, Slashdotters, we have a live, squirming specimen of the bane of the Info Age: "Echd'oh". The website publishes a story (about a 250My-old event), exaggerates the headline (pulling a 2Gy background detail into misrepresenting the entire story), a blogger doesn't RTFA, quotes only the mistaken headline, an irrelevant argument about the incorrect details blooms on the blog. For good measure, a carping blogger invents a neologism to describe the phenomenon, guaranteeing its easy repetition in the blogsphere, even a fad of its own overwhelming the original story, mistake and debate, which are lost in the memory hole.
For our next trick, this thread will pick a different term to describe this phenomenon, which plays on a minor characteristic, spawning mutated copycats trying to fulfill the new term, which will become more popular than the original phenomenon. Behold the mutamemic blogsphere!
--
make install -not war
I was raised as a Christian and a scientist (not a Christian Scientist however ;>), so your conclusion is inherently flawed at first.
Second, I checked out the site you mention, and not only is it flat wrong about many a lot of factual evidence, it isn't even one of the better creationist sites I've seen. It's one of those "this specious evidence doesn't correlate 100% with the conclusion that the earth is 4.5 bn yrs old, so the earth is really 4000 years old" sites. They ignore an immense amount of evidence that doesn't support them, while focusing on poorly measured, nearly irrelevant information that doesn't even usually support their conclusion. Care to explain carbon and potassium dating, please?
They aren't even correct about their representations about what scientists actually believe about evolution nor creation - such as modern humans evolving from Neanderthals, or "Lucy" being a chimpanzee.
A little advice - taking literal assumptions from a 3000 year old document that's been translated, poorly, many times, isn't a good idea. Try this. http://www.orisol.com/chap08.html
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.
What's wrong with magnitude 11?
The Richter scale does not have an end. It measures the energy release of an earthquake on an exponential scale, meaning that a magnitude 5 earthquake is an order of magnitude more energetic than a magnitude 4 earthquake. Hence the usage of the word magnitude.
Not that the evidence isn't also compatible with creators / designers... but those designers are not only plagarists, but very bad plagarists. Not only have they never surprised us with original code, the copies / plagarism also include copies of all previous copying errors (like the primates having an almost working- but for a few errors- version of vitamin C manufacturing. Yay scurvy: other mammals don't have to worry about it.)
in a word: Yes.
Read some books by Stephen J. Gould.