Lava Flow May Have Caused Extinction

Pinhead writes "From MSNBC, it appears a new study suggests that a massive extinction that occurred 250 million years ago may not have been an asteroid but a large lava flow that spewed large amounts of poisonous gases in the air. This extinction led to the rise of the dinosaurs." Note that there are two different big extinctions: this first one occurred when plant life was mostly ferns, and all the continents were together in Pangaea. The later one is the one that everyone knows about, that wiped out the dinosaurs.

Comments

No problem

[MMMMMMMMMMMMMMMMMMMM]

I repair Lava Lamps.

I knew it was powerful

[Anonymous Coward]

Lava Soap is great for cleaning oil off your hands and arms and everything, but, jeez, I didn't realize it could cause mass extinction. Guess I'll be more careful next time I use it.

You know what this means!

[ObviousGuy]

Thar's oll in them thar hills!

A volcano might have affected humans too

[PD]

There's some genetic evidence that humans were reduced in number from 100,000 to 10,000 about 75,000 years ago. Some think that it was because of a major eruption in Indonesia.

Browse This Google search for more information.

Re:A volcano might have affected humans too

[Anonymous Coward]

How close are you to your 20 bogus posts?

everyone knows the world has only been here for 10,000 years. it's in the bible ;-)

oh yeah, bible == fiction.

Re:A volcano might have affected humans too

[Anonymous Coward]

You take a very narow view of what God can do. If God wishes to have a real story that predates time, he will. Is the fossil record here to be ignored? God has a real plan; I do not think that I can out guess God's plan.

Re:A volcano might have affected humans too

[Anonymous Coward]

Heh. Right.

not just two mass extinctions...

[palndrumm]

Note that there are two different big extinctions

There's been a lot more than just two mass extinctions over the history of the earth - there's evidence of events where up to 90% of existing species have disappeared scattered throughout the fossil record. Some of these have probably been caused by meteorite or comet impacts, others quite possibly by large geological events - massive lava outpourings can release enough CO2 into the atmoshpere to have a definite effect on world climate.

There's been a lot more than two

[ynotds]

Note that there are two different big extinctions

There are generally five biggies identified since the "Cambrian explosion", the sudden diversification of animal body plans/phyla, these being identified with the Cambrian, Ordovician, Devonian, Permian and Cretaceous geological periods.

However it doesn't take a lot of imagination to realise that the abrupt changes in the rocks which have long guided geologists to divide geologic time into distinct epochs must be due to global changes in the ecology, especially in marine microorganisms ... the smoking gun for the late Stephen Jay Gould's theory of punctuated equilibrium.

This overview of the big five events and their causes shows them bracketed by a pair that led into the Cambrian explosion and a seemingly human induced one.

There is a lot of conjecture about causes for specific extinction events, IMNSHO mainly due to the growing human (and especially scientific) demand that causes be singular. Purported causes include extensive glaciation which is relatively easy to spot in the geological record, flood volcanism, which is a bit harder because it is relatively localised, and impacts, the most recent of which at least managed to leave a layer enriched with iridium and a large crater.

But even re that most recent dinosaur ending event there is still evidence that the Deccan Traps lava flood may have played a role, as there are persistent claims for impacts as well as Siberian lava flows around the time of the real biggie at the end of the Permian which this article focuses on.

Personally I'm leaning more and more towards a double whammy theory of mass extinction that would require some sustained global stress complemented by a more sudden knockout punch. And that doesn't get humanity off the hook.

Of more consequence for populist misinterpretations of Darwin's great insights is that it has needed the slate to be wiped almost clean many times before an opportunity arose for mammals, let alone humans, to rise to prominence.

As co-conspirators in the rise of imformation technology we should be able to see the importance of mass extinctions opening opportunities for those who may be better at innovation.

Re:There's been a lot more than two

[palndrumm]

Yeah, what you said.
(Isn't it always the way - as soon as you post something, someone comes along and says the same thing but in more detail and with links and references too...)

Heh :)

[CyberDruid]

I am actually having an exam on this subject in 30 mins. Guess I'll come loaded with _the latest_ developments...
Seriously though - that the 250 m.y.a. extinction was not caused by a asteroid, but by volcanic activity in Siberia, has been the general opinion for quite some time.

first cock

[isorox]

Cockney old sod did contract penis tumors juggling cold testicals quickly

A nice easy rhyme to remember

Cambrian - Ordivician - Silurian - Devonian - Carbiniferous - Permian - Triassic - Jurassic - Cretaceous - Tertiary - Quaternary

The dinousaur one was at the K-T Boundry (Cretaceous - Tertiary), end of the mesozoic IIRC.
The other big one (trilobites and about 90% of the earth - I think, its been a few years) was this one, and at the start of the mesozoic (Permian - Triassic)

Lavaflow from MSNBC?

[epsalon]

Well we know M$ is bad, but MSNBC extincting an entire species with a lava flow?

Admit it, you're a geologist

[amorsen]

The other big one (trilobites and about 90% of the earth - I think, its been a few years)

Some might even say more than a few years.

Re:Admit it, you're a geologist

[isorox]

nah, did a 2 year geology course from ageed 16 - 18 (top 2 years in high school) called an alevel. Scraped a 'D' (about 50%) in july 2000.

Rise of the dinosaurs

[ammonoid]

The attempt by the BBC to link the rise of the dinosaurs to the Permo-Triassic extinction is a mistake. Both synapsids (mammalian lineage) and diapsids (dinosaur lineage) coexisted during most of the Triassic. Then at around 210 M.y. there was a sudden shift in the diversities of the two groups, which allowed the dinosaurs to dominate the terrestrial ecosystems until the end of the Cretaceous. This does not seem to be related to competitive interactions between the two groups, and may have been driven by an extinction event towards the end of the Carnian (a Triassic subdivision). The full reference is: Benton, M. J. 1983b. Dinosaur success in the Triassic: a noncompetitive ecological model. Quarterly Review of Biology, 58, 29-55.

Fairy tales

[Anonymous Coward]

This story should start with "Once upon a time". Where is the hard evidence? Where is the experimental proof? Science is supposed to be a process of propose a hypothesis, design and conduct an experiment to test that hypothesis, and refine or reject the theory based on that experiment.

But stories like this are based on the assumptions that everything now is exactly as it always was (the Uniformitarian philosophy). No experiment can tell you what happened 4 thousand, 4 million, or 4 billion years ago. You have to accept on faith that conditions were just like today in order to believe these stories.

And believing based on faith is a religion, not science. Let's just deal with facts, not faith, when talking about science.

Re:Fairy tales

[ammonoid]

The return of catastrophism to geology was marked by the widespread acceptance of the bolide impact at the K-T boundary. An excellent book on this subject is "Mass extinction debates: How science works in a crisis" William Glen (ed.). Most geologists accept that there are events in the geological past that have no present analog. As to your rather narrow vision of "the scientific method", this falsificationalist view is that of the earlier works of Karl Popper. Historical science is inferential, and tries to assign probabilities to what happened, just as human histories do. As for what experiments can tell you, the Miller-Urey experiment told us something about how the possibility of complex organic molecules emerging. That is an experiment that tells us something about what might have been going on 4 B.a. As to the rates of eruption quoted in the article, there is abundant radiometric dating evidence from the Siberian Trappes. The rate of eruption is then simply the change in rock area or volume over the calculated time. The links to the mass extinction may be more tenuous, but there is no question that a major change in the marine organisms occurred aroudn the Permo-Triassic boundary.

Re:Fairy tales

[Anonymous Coward]

Miller-Urey is the biggest joke in the world, what a great example of pseudo-science. First, it assumed a very low to trace level of oxygen, now not assumed to be true. But even more important, the amino acids found (glycine and alanine) are the simplest two. And the alanine was racemic, not unichiral as it is in life forms. And they were formed in a solution of carbonic acid and tar, which would destroy any macromolecule far more rapidly than the formation rate.

But even more significant, if the primordial atmosphere were low in oxygen, there would be no ozone layer, and there would be a LOT of UV. That would mean the NH3 (ammonia) would be dissociated rapidly and unavailable for reactions. But if there were enough oxygen to allow an ozone layer, allowing the existince of NH3, the Miller-Urey experiment would fail as the reactions only work in trace levels of oxygen.

Re:Fairy tales

[Anonymous Coward]

Yeah, get your creationist mumbo-jumbo out of the way. Let's extend your philosophy forwards - can an experiment tell you what happened 4 seconds, or 4 minutes ago ? If so, what's the big deal with longer spans of time?

Stories like this are actually based on the blindingly obvious - really, really big lava flows like the Siberian Traps had huge enviromental effects and could well have caused mass extinctions. I don't have to "believe that conditions were just like today", which is good, because if you were dumped back in the Permian, even you would be able to notice the numerous differences. All I have to do is posit that massive amounts of outgassed CO2, sulphates, and particulates weren't especially helpful to animals and plants. Which they're not. Funny, I don't see where that became belief based on faith ...

Back to Answers in Genesis for you, troll-boy ...

Re:Fairy tales

[Anonymous Coward]

Engaging in reductio ad absurdum argumentation won't assist you, the key point is that there is no way to prove the Earth is billions of years old. Yes I know about radiometric dating; go read Woodmorappe's book "Mythology of Modern Dating Methods", ISBN 0932766579 for a clear explanation of why it is not believable.

But consider this, the geologic "column", the billions of years, and the index fossils for each layer were picked out in the 1800's. Long, long before radiometric dating was practiced. Then radiometric dating came along, and was "calibrated" to fit the column. A clear example of Finagle's Rules in action. Science should examine the facts, then interpret them. Doing this the other way around is following a faith, not practicing science.

For example, rocks from the newly forming lava dome at Mt. St. Helens were sent to the same labs used by lots of other geologists by a PhD geologist. The results were that the rocks were 350,000 to 2,000,000 years old. But the rocks were known to be 8 years old at the time. There are many other cases of the same sort of thing happening; the basic principle being that when the age is known by external means, radiometric dating is wildly wrong. But when the date is not externally known, radiometric dating is assumed to be correct. That is not science, it's nearly blind faith.

Re:Fairy tales

[Anonymous Coward]

Can't say I'm about to go and spend a few pounds on some ICR stuff, but here's someone who has, and wasn't very impressed.
http://home.austarnet.com.au/stear/hid ing_the_numb ers_woody_henke.htm

I'd be delighted if you could show me where any of the folk who did the early key work on index fossils or stratigraphy claimed 'billions of years' of age - I don't recall seeing that in Hutton, or William Smith, or Sedgwick, or indeed anyone else. People might toss around 'millions' by the mid-1800s, but the real age of the earth was initially suggested by early radiometric dating which is a firmly 20th-century post-Soddy technique. I think you might be confusing stratigraphic sequence relative ordering via index fossils with radiometric dating.

By the way, I suppose you don't think the Universe is very old either, and that's got very little to do with radiometric dating ... sheesh, I think you've got trees in the US that are older than 6000 years.

Re:Fairy tales

[Anonymous Coward]

Oh, yes, the ususal creationist dating fraud. Take something made of old materials, make something new from it. The radiometric testing indicates the age of the materials, but the creationist yell, "but it is only X years old! - It doesn't work!". This is what some call "Lying for Jesus".

Re:Fairy tales

[young-earth]

By 1900 textbooks were claiming the Earth was 2GYa. Decades before radiometric dating. Yes Hutton, Lyell, etc. were in the millions not billions of years, but those following them extended it.

By the 1960s we were taught the Earth was 3.5 GYa, and now it's 4.5-4.6 as "conventional" wisdom.

BTW trees put on rings based on seasons, and many cases are recorded of multiple rings per annum.

Re:Fairy tales

[Anonymous Coward]

What was done at Mt. St. Helens and many other places was to take a rock from the dome that was of known age and test it using the same radiometric testing labs as evolutionists do.

The only difference between that test and others is that the rock was of a known age. Any qualifications invented to disqualify or excuse the age are equally applicable to rocks in proving the earth is ancient. Claiming the rocks are different because they were observed in formation is obfuscatory and wrong.

link

[waterbiscuit]

nature.com has this story about it too. Seems fairly closely matched with the displayed link.

Perhaps an asteroid AND a lava flow

[JPMH]

It's been suggested that if you get an asteroid impact, the outgoing shockwaves may be refocussed by the curvature of the earth to produce a region of very high stress in the area of the globe diametrically opposite from the impact point. If this happens to co-incide with an area of weakness in the earth's crust, the suggestion is that the stress from the impact could actually cause the crust to rupture, and trigger a wide-area volcanic event.

The Chicxulub crater in Mexico is very nearly opposite the Deccan traps, which have both been fingered for the extinction of the dinosaurs 65 million years ago. There is also a possible large impact site in Australia of the right age, which would have been almost exactly opposite the Siberian Traps at the time of the Permian extinction 250 million years ago. On the planet Mercury there is a gigantic impact crater called the Caloris basin, which is also directly opposite "weird terrain" caused by focussed shockwaves.

Summarised from Terry Pratchett et al, "The Science of Discworld", pp 307-308, discussing mass extinctions, and the surprisingly essential role they appear to have played in the evolutionary history.

Drinking milk

[BigBong]

Hello?!?!?!?

Wouldn't a massive asteroid, say the likes of the one that cuased the creation of the Yucatan peninsula and the deepening of the Gulf of Mexico (discovered by no other than the Shoemaker-Levy dynamic duo based on satellite photos), cause some MAJOR seismic/techtonic/volcanic activity?

If someone punches you in the stomach while you are swallowing some milk, it's gonna shoot out of your mouth, nostrils, and possibly your ears.

Same thing with Earth. Punch it in the Yucatan and shit is gonna spray everywhere. Lava, dust, critters...everything.