Talk:Great Oxygenation Event
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- 1 Too Technical, Missing Points?
- 2 Introductory color visual or graph
- 3 Cyanobacteria
- 4 The oxygenation of the atmosphere and oceans
- 5 When did ozone layer appear?
- 6 Capitalization
- 7 Image caption
- 8 Requested Move
- 9 What exactly was the "catastrophe" ?
- 10 Sources
- 11 Article title
- 12 Graph Lines?
- 13 Drake Equation
- 14 2,400 million years ago?
- 15 Atmospheric composition
- 16 Volcanism
- 17 Timeline formatting problem
- 18 table broken?
Too Technical, Missing Points?
I have an MSc in Physics and I think this page is way too technical, or unfortunately is written in a way that makes it much less interesting. (no offence to the hard working souls who created it). There is a huge middle section that goes off on a technical tangent about a time lag, and only near the end do we get to the explanation of what actually happened. It also seems that there is no mention at all of the Snowball Earth or how the snowball earth was eventually broken by more microbes that evolved to consume oxygen and create carbon dioxide. I found the DamnInteresting page on this event to be much more readable. It follows events chronologically and explains cause and effect in less technical language, as opposed to explaining one or two technical points in verbose detail. (http://www.damninteresting.com/?p=673#more-673) 126.96.36.199 04:35, 3 December 2006 (UTC)
- The Snowball Earth was several billion years later, so I don't see that it's directly relevant to the Oxygen Catastrophe. But yes, this article could certainly do with some work, I'll try a rewrite if I have time. -- Danny Yee 08:09, 3 December 2006 (UTC)
- Also, the story on the DamnInteresting page is highly speculative. It goes into details that are certainly not known but simply guessed at. -- Danny Yee 08:10, 3 December 2006 (UTC)
Before a hyper-technical term like "oxy-photosynthesis" appears in a sub-title, it MUST be defined! I myself am shakey as to what the writer here actually meant by this difficult-to-pronounce scientistic term. Dr.Bastedo (talk) 01:20, 27 June 2010 (UTC)
- Dr.Bastedo, please do not SHOUT!
- When I refer to an article or or page, I provide a link - please do the same.
- The article used "oxy-photosynthesis" only as a heading, not in text. Photosynthesis#Evolution is interesting but that section has no citations. Microbial mat is also very interesting, but the sources have limitations: Nisbet describes his one as speculative, and Krumbein and co get too enthusiastic and and I doubt their objectivity (I wrote the WP article).
- If you find any good sources for any of this, please ensure that the citations have the required parameters: last1, first1, etc.; pages for all except pure web pages; url and accessdate if a url is available for a non-web source; etc. --Philcha (talk) 00:37, 28 June 2010 (UTC)
Introductory color visual or graph
The "Great Oxygenation Event" (G.O.E.) has the SAME colored visual or line-graph that appears at the START of the "Geological history of oxygen", a much-better and more readable Wiki article.
However, we need some illustrations for G.O.E. So either we should (1) colorfully revise the current graphic as -- say -- a differently-colored histogram/barchart, or (2) come up with better alternative illustrations -- e.g., a diagram, flow-chart, photo, cartoon, artwork, or colorful data.
For more ideas, I recommend Prof. Edward Tufte's colorful how-to books on how to present statistics, science and history.
In short, we should avoid redundancy, plagiarism, dejavu, and confusion with the other article(s). And I'm way too old and too retired to fuss with all the details... Dr.Bastedo (talk) 02:07, 27 June 2010 (UTC)
It would be useful to mention that the cause of the oxygen build up was the evolution of photosynthesising cyanobacteria from earlier photosynthesising sulphur bacteria. Photosynthesising sulphur bacteria use sunlight to split Hydrogen Sulphide (H2S) molecules to produce sulphur, but cyanobacteria modified this process to split water (H20)molecules to produce oxygen. RV 4 March 2007
The oxygenation of the atmosphere and oceans
This 2006 paper by Heinrich Holland lucidly reviews the subjects covered in this article. Professor Holland has kindly released figure 10 from his article under GFDL, for us to be able to use it in Wikipedia. These graphs illustrate the estimated evolution of atmospheric and the concentration of O2 in the shallow and deep oceans. Your assistance is now needed to adapt these graphs for use in Wikipedia, and update our articles with the information provided in the said paper. Regards, Lior 17:03, 11 June 2007 (UTC)
- The presentation of information D.I. End of Life here, deleted as "blogspam" [sic] might prove useful in improving the presentation in this Wikipedia article. --Wetman 17:14, 18 June 2007 (UTC)
When did ozone layer appear?
I thought that ozone layer appeared 500 millions years ago, when land became habitable (see Timeline of evolution). However this article relates its appearance with the much earlier Oxygen Catastrophe. Is it a real discrepancy, or are we talking about two different phases in its forming (i.e. for a stable 21% oxygen atmosphere one needs a much thinner ozone layer compared to the one needed for the land to become habitable)? Dan Gluck 09:41, 17 September 2007 (UTC)
- The use of capitals in phrases like "Oxygen catastrophe" is unwarranted. --Wetman 18:56, 7 October 2007 (UTC)
- I'm proposing moving the page to the non-capitalized version (which redirects here). - tameeria (talk) 20:09, 30 December 2007 (UTC)
- There was only one oxgen catastrophe, so the expression may as well have capitals as a proper name of a specific event. Anthony Appleyard (talk) 21:10, 30 December 2007 (UTC)
I agree that it was a specific event that can have this title.
- The source paper of the diagram does not seem to suggest these time frames either (PDF available here). Strangely, the phases A, B,C are in addition to the stages 1-5, which are not linear in time. Linear time scale is indicated at the bottom of illustration. --188.8.131.52 (talk) 21:08, 9 December 2007 (UTC)
Oxygen Catastrophe to oxygen catastrophe
- Oppose as it refers to a specific and not a generic event. 184.108.40.206 (talk) 00:48, 2 January 2008 (UTC)
- Oppose, probably. The stuff I can find usully doesnt have a capital 'C', but if we dont write it like that people will think its about a general phenomenon, not a specific event. Callmederek (talk) 19:18, 4 January 2008 (UTC)
- Oppose per comments above; specific event --Lox (t,c) 12:55, 5 January 2008 (UTC)
- Looks like the consensus is not to move the page, so I'm removing the move tag. - tameeria (talk) 16:33, 5 January 2008 (UTC)
What exactly was the "catastrophe" ?
I didn't find anything that actually explained what was so catastrophic to justify the title. What/how much actually happened ? Did existing lifeforms disappear, move underground, evolve ? Anaerobic organisms still exist. The availability of O2 seems more like a great opportunity than a catastrophe.Rcbutcher (talk) 02:53, 18 January 2008 (UTC)
The rising oxygen levels wiped out a huge portion of Earth's inhabitants at the time. From their perspective it was a catastrophe. Cyanobacteria were essentially responsible for probably the largest extinction event in Earth's history. Eris Discord | Talk 02:35, 29 February 2008 (UTC)
- Eris, do you have any source for that statement? If so, exactly what would have killed off the previous species? What were the previous species? --Mlewan (talk) 15:34, 11 March 2010 (UTC)
- The catastrophe was only ever hypothetical, there is no actual evidence of mass extinctions after the oxgen content of the atmosphere started rising. A recent paper (Energy metabolism among eukaryotic anaerobes in light of Proterozoic ocean chemistry, Royal Society, 2008) summarises current ideas about the issue. The idea of an oxygen catastrophe is based on ideas about the evolution of the biosphere that originated in the 1970s. Evidence found by microbiologists and geochemists since the 1990s paints a different picture, although the oxygen catastrophe hypothesis is still widely written about by scientists who are not specialists in these fields (Google Scholar give tons of hits for "oxygen catastrophe" but only a few for "oxygen catastrophe" evidence). The biological evidence consists of the existence of non-aerobic eucaryotes throughout the eucaryote family tree, not just in a few "primitive" groups - some plants and fungi are obligate (full-time) anerobes, and some plants, fungi and animals are facultative anerobes (can live without oxygen if circumstances require it). The geochemical evidence indicates that until about the oceans remained anoxic and sulphidic, except possibly in the top 100-200 meters where there was enough light to support photosynthesis. (end of summary of paper). IMO it's very likely that oxygenation had effects on life from the start, but these were nowhere near as massive and abrupt as the phrase "oxygen catastrophe" implies. --Philcha (talk) 12:03, 2 December 2008 (UTC)
- 'Catastrophe' doesn't refer to mass extinction but to the abrupt rise in oxygen levels (compare ultraviolet catastrophe; the reference is to how the graph looks, not to disastrous events speifically). 220.127.116.11 (talk) 07:31, 4 February 2010 (UTC)
- 'Catastrophe' can be read both ways: A lethal event and a "sudden shift in behavior arising from small changes in circumstances" (see Catastrophe theory). As a name for what happened to the oxygen levels I find it apt. -- Zirconscot (talk) 23:10, 3 December 2011 (UTC)
- I feel that the article still needs to speak about the name Oxygen Catastrophe- if it is true that for years it was percieved as a catastrophic death etc, then we need to say something about realising that this is not known, since books and other media have long called it a Catastrophe. Don't get me wrong, I was one of those who wanted it to have another name etc, I just feel that if only in a historical context the common word Castastrophe needs explaining.
Recent publications suggest we need to re-examine the whole idea of an "oxygen catastrophe". I'm going to start collecting sources here, with brief notes. If we get enough, it may be necessary to re-organise the list into sub-sections. Please contribute, using a similar format. If you wish to discuss any of these items, please do so in separate sections, so that this remains a simple list.--Philcha (talk) 12:14, 2 December 2008 (UTC)
- Energy metabolism among eukaryotic anaerobes in light of Proterozoic ocean chemistry (Mentel & Martin; Phil. Trans. Royal Society, 2008) - The existence of non-aerobic eucaryotes throughout the eucaryote family tree, not just in a few "primitive" groups, and the very narrow range of energy-producing chemical paths eucaryotes possess, suggest that eucaryotes acquired mitochondria / hydrogenosomes / mitosomes in a single endosymbiosis event that happened in an anerobic environment. Geochemical evidence suggests the oceans remained anoxic and probably sulphidic until about , except for the photic zone in the top 100-200 metres.
- Dating the rise of atmospheric oxygen (Bekker, Holland, Wang et al; Nature, 2004) - Oxygenation of atmosphere started about and reached 10-5 PAL (present atmospheric level), enough to become significant, by .
- The oxygenation of the atmosphere and oceans (Holland; Philos Trans R Soc Lond B Biol Sci., 2006) - Stages: atmosphere and oceans anoxic, except possibly "oxygen oases" in shallow oceans; atmospheric oxygen levels rose to between 0.02 and 0.04 PAL, shallow oceans became mildly oxygenated, deep oceans remained anoxic; (the "boring billion") little change in atmospheric oxygen levels, surface and deep oceans mildly oxygenated, anoxic or euxinic deep oceans not inevitable; atmospheric oxygen rose to about 0.2 atm, shallow oceans oxygenated, deep oceans anoxic at least some of the time(three major Neoproterozoic glaciations); to present show atmospheric oxygen rising to 30% in Carboniferous ("wood crisis") then declining to present level (about 18%), shallow oceans were oxygenated, oxygen levels in deep oceans fluctuated, possibly sharply at times.
- The loss of mass-independent fractionation in sulfur due to a Palaeoproterozoic collapse of atmospheric methane (Zahnle, Claire, Catling; Geobiology 2006) - Collapse of atmos methane level a prerequisite for oxygenation; collapse of methane greenhouse enabled Proterozioc glaciations; stable oxygen level restored methane greenhouseby protecting it from UV with ozone layer.
- Did the Proterozoic ‘Canfield Ocean’ cause a laughing gas greenhouse? (Buick; Geobiology 2007) - not sure how serious, but start and finish are amusing (deliberately).
- Oxygen and life in the Precambrian (Catling, Buick; Geobiology 2006) - Summarise all the other Geobiology 2006 papers.
- Bistability of atmospheric oxygen and the Great Oxidation (Goldblatt, Lenton & Watson; Nature, 2006) - Oxygenic photosynthesis evolved about but the "Great Oxidation" was about ; man yexplanation so fthis lag have been proposed. Possible explanation - atmospheric oxygen level is bistable: below 10-5 PAL there is too little O2 to form an ozone layer, and UV drive oxidisation of methane; above 10-5 PAL, ozone form and blocks UV, so O2 and methane levels rise again. This model predicts a sharp fall inmethane levels during the transtion, setting the scene for glaciations.
- The Emerging Aerobic Earth System through Archaean-Palaeoproterozoic Transition: Problems and Perspectives (Melezhik, Fallick, et al; Geophysical Research Abstracts, 2006) - some puzzles, including first appearance of petroleum about }.
- The rise of atmospheric oxygen (Kump; Nature, 2008) - A failed oxygenation event about ago?
- Atmospheric oxygenation event is free, what about a move to a less dramatic title? Tim Vickers (talk) 21:10, 15 January 2009 (UTC)
- That's better, but I'm not sure "event" is right for a 16,00M yr process. How about Atmospheric oxygenation? That leaves the options open, whichever way the geochemists jump.--Philcha (talk) 21:41, 15 January 2009 (UTC)
- No, that might be an ambiguous title that could also refer to the oxygen cycle. This is something that happened once, within defined boundaries (however long these were), so I think "event" is technically accurate. Tim Vickers (talk) 21:56, 15 January 2009 (UTC)
- Sounds good, but you'd then have to expand the article a bit to include later fluctuations after the initial reducing/oxidising switch, since that title covers a broader subject area. I'd be happy with that as a solution though. I wonder if anybody else watching this page will comment? Tim Vickers (talk) 22:53, 15 January 2009 (UTC)
I think that if we can settle that there was not a Catastrophe, then the bulk of the article, describing what actually happened, should move to Atmospheric oxygenation event. It doesn't really matter whether anyone has used it before or anything, so long as it establishes the truth as accurately as we know. I think that a small article should remain here about the original idea, that it was "The biggest extinction in history" or whatever, and showing any key research which discredits this- linked to a main article over there. I have been bold and created the page, in brief, wikidragon fashion.
- I don't think we can (or should) settle that there wasn't a catastrophe.
- BTW, there is an interesting take in New Scientist on it - claims that the GOE triggered a much earlier snowball Earth episode. See First breath: Earth's billion-year struggle for oxygen. A rare high quality article from NS. --Michael C. Price talk 17:32, 7 February 2010 (UTC)
I do not understand, why the Title here is "Great Oxygenation Event", while specialists like H. Holland (in ref.1) call it Great Oxidation Event" - my english is not the best (sorry for this) but shouldn't we call things like this as Specialists do it? -- Hartmann Schedel cheers 12:14, 16 May 2013 (UTC)
Am I missing something? There are two different coloured lines on the graph and only one atmostpheric constituant discussed, so what does the other line mean and which is which?
This is intended as a stub until either I or anyone else can fully illustrate the significance of this portion.
By many accounts, the Drake Equation is roughly 13 to 14 orders of magnitude higher than we are experiencing, taken even for when the anecdotially reported myriad forms of intelligent extraterrestrial life are accounted, totalling roughly more than one, perhaps 10, and far fewer than 100 distinctly differeing species. In order to rectify the Equation, I postulate that the condition of the earliest times of the planetary evolutionary cycles be admitted as another variable to the Drake Equation, somewhere between fℓ and fi, considering the exegesis of particularly protozoan life from those same conditions on early planet Earth.
This is not necessarily a case of making the equation fit the data results, although it appears to be exactly so.
It is my hypothesis that this hypothetical Great Oxygenation Event, which seems to have formed the Ozone Layer, atmospheric and oceanic oxygen, and many useful minerals for life on Earth, could happen only extremely rarely, and could perhaps wholly account for the remaining roughly 1/10,000,000,000,000 (1 in 10 quadrillion) chance that life evolved here and not everywhere else. The quantification of the rarity of this event would help to define one element of the proposed additional variable to establish a realistic number for the Drake Equation. The additional rarity of the progression of life on Earth to anti-photosynthetic form could possibly have been predicated by a disruption of another extremely large impactor into the atmosphere, and is also deserved another element of this proposed variable, although these two do not comprise the exclusivity of that variable.
This other part of the entire hypothesis is that it appears to me that the entirety of the Canadian Shield, including Greenland, seems to be formed from a giant impactor which formed the crater now known as most of the Hudson Bay area. I would like it if more research was done to confirm or deny whether or not the Hudson Bay area in general, and the Canadian Shield at large is the result of a rather large and early (c.2,700M-3,400M years ago) impactor against the surface and early atmosphere of the Earth. When one compares the Canadian Shield to the Hellas Basin on the surface of Mars, the geological similarities are convincingly striking, albeit in roughly half the size, and although certainly not conclusive. More work, specifically using core samples from various locations surrounding the Hudson Bay area, would be requisite to begin to either confirm or deny this hypothesis.
The number for this variable may be revised upward if we do find through telescopic radiometry and spectrography a larger prevalence of oxygenated worlds in other solar systems within the galaxy.
This section in its entirety is being cited as an original derivative work, from my own making.
This is all posted as a postualtive, and not under copyright, although attribution would be appreciated under Creative Commons License.
- Your speculations are nonsense and will be removed as they violate 2 policies of WP, No original research and Verification. --Philcha (talk) 17:54, 2 June 2010 (UTC)
2,400 million years ago?
The article does not make clear what the current consensus is about the total atmospheric composition before, during, and after the event. Meaning percentage of nitrogen, carbon oxides, hydrogen, methane, ammonia, noble gases, etc., as well as the rise in free oxygen. It's odd to see, for example, a paragraph about the reduction in atmospheric nickel without actual numbers for the much larger constituents. --18.104.22.168 (talk) 21:40, 19 November 2012 (UTC)
This article does not address the theory that this event was caused by volcanic changes rather than cyanobacteria. For example, see this article in Nature http://www.nature.com/nature/journal/v478/n7368/full/nature10460.html or the studies of H.D. Holland (Harvard). It appears that there is some debate in the scientific literature over what actually caused this event. — Preceding unsigned comment added by 22.214.171.124 (talk) 15:48, 24 April 2013 (UTC)
Timeline formatting problem
In the timeline in the "Role in mineral diversification" section, the Quaternary period spills over onto its own row (at least in my browser), where it is aligned with a large chunk of the early Paleoproterozoic era. This is obviously very misleading, but I don't understand the timeline template well enough to fix it. Can someone help? Ravi12346 (talk) 21:03, 27 May 2013 (UTC)
Most of the information under "Timing" is covered again immediately afterword in the "Time Lag Theory" section. Can these sections be combined, or else differentiated more?126.96.36.199 (talk) 15:41, 29 May 2013 (UTC)
Million years ago. Age of Earth = 4,560
perhaps I've just misunderstood it (in which case it could do with more labels). EdwardLane (talk) 12:24, 30 May 2013 (UTC) Quaternary is definitely in the wrong place in this drawing as displayed on my browser - it is shown on the far left, at the most distant time from the present, which doesn't make any sense if you follow the links. Perhaps it has wrapped around? Jintian (talk) 19:13, 23 June 2013 (UTC)
ok looks like periods is the template that has gone wrong, documentation is not present, so here's my best attempt at fixing it so far but it's still not right as, for example 'The Cenozoic is divided into three periods: The Paleogene, Neogene, and Quaternary;' but those are not lined up.
Million years ago. Age of Earth = 4,560
looks like this is beyond my skills, so I've put a request on Wikipedia_talk:WikiProject_Templates#Template_horizontal_timelines . EdwardLane (talk) 07:54, 29 June 2013 (UTC)