Talk:History of Earth/Archive 2

Now that I've finished writing the inital drafts, I'm trying to make this article extremely well-referenced. However, I am an amateur, and am not up-to-date on the latest research in the many fields this article spans. If you have additional references, or can improve on the ones I've selected, please make the appropriate changes or leave a note on this talk page. Thanks! — Knowledge Seeker দ 07:14, 3 April 2006 (UTC)

I've had relatively good success in finding appropriate references, but there are some that have me stymied. — Knowledge Seeker দ 07:18, 3 April 2006 (UTC)

• Does anyone have a good reference for when LUCA might have lived? I want to use it for History of Earth#The First Cell — Knowledge Seeker দ 07:18, 3 April 2006 (UTC)

• Any references for the Cambrian-Ordovician extinction events (both existence and timing)? I got the information from the corresponding Wikipedia article but we need an external reference. — Knowledge Seeker দ 07:18, 3 April 2006 (UTC)
  • Complete, thanks to User:Rickert. — Knowledge Seeker দ 03:37, 9 April 2006 (UTC)

• Having trouble finding a reference for when seeds evolved. Timeline of evolution pegs it at 360 Ma; I asked there if anyone had a citation. The best I've found so far is a PNAS article suggesting "Later [after early mid-Ordovician] in the Paleozoic" and this web site suggesting "at the end of the Devonian". Anyone got anything better? — Knowledge Seeker দ 05:44, 7 April 2006 (UTC)
  • Complete, thanks to User:Marknesbitt. — Knowledge Seeker দ 07:32, 8 April 2006 (UTC)

• How about citations for when Pangaea assembled and broke up? That article states 300 Ma–180 Ma. Can anyone confirm? — Knowledge Seeker দ 04:03, 9 April 2006 (UTC)
  • Unsure if this has been addressed, but the breakup of Pangaea occurred at different times. That is, not all of the continents split apart simultaneously. The ranges given, therefore, are appropriate. I believe is not necessary to address the details here as they are covered in the article for Pangaea. — Theinsomniac4life 22:03, 27 January 2007 (UTC)

• Other articles refer to this one for earth's timeline. For obvious(?) reasons, it would be helpful to nail down (with citations) the current state of thought with respect to the two dates that bound the origin of life section: a) when is earth thought to have cooled enough to support organic molecules; b) what is the earliest known date of the earliest life form on earth. I've heard these dates are most recently in the 3.8-3.9 range. — Mr Pete 10:32, 8 May 2007 (UTC)

In response to my request for feedback on this article, I received a helpful reply. Guettarda suggested that there is perhaps an overemphasis on biology, especially once life evolves I tend to abandon geology and such. This reflects my bias as well as my knowledge state; and I've had more trouble finding information on the geologic events. As he points out, I would like to put more information on some major geologic events and climate changes, but I know little about these areas. Perhaps others can assist me with this or at least point out areas that should be included. Some that come to mind offhand are as follows:

• Late Heavy Bombardment
• Snowball Earth?
• More about ice ages
• More about continent movements such as Gondwana and Laurasia, more if I can find references
• How climate changes might have contributed to major evolutionary events
• Origin of some major mountain ranges, like the Himalayas

Obviously, this is an overview article, and we cannot mention all events. What am I missing? Any other suggestions? — Knowledge Seeker দ 03:20, 16 April 2006 (UTC)

I was going to make the same suggestion. I think one good way to include geology and climate would be to structure the article around the global supercontinents, especially the last three: Rodinia, Pannotia, and Pangaea. Climate and geology are intertwined, and the supercontinents exhibit that connection to the extreme. In Earth's history, the formation and destruction of supercontinents (the supercontinent cycle) are probably some of the most significant and most salient events. Other important climatic and geologic events are related to the "big five" mass extinctions (Ordovician-Silurian , Devonian, Permian-Triassic, Triassic-Jurassic, Cretaceous-Tertiary), which is another topic you could structure around. The P-T extinction is particularly intriguing; I would at least mention the Siberian Traps. bcasterline t 04:38, 16 April 2006 (UTC)

I should also mention Christopher Scotese, who has good information for a general overview and perspective. bcasterline t 04:46, 16 April 2006 (UTC)

Thanks for the feedback. I'm not sure what you mean about re-structuring the article—those three supercontinents form only a part of Earth's history; all fall within the "Colonization of land" section unless I am misunderstanding something. I'm trying not to overemphasize any period of Earth's history; I know that I have followed the progression of life for the most part but the time from the assembly of Rodinia to the breakup of Pangaea only cover a fifth of Earth's lifetime. Still, I will try to include some more information about accompanying climate changes; it is a bit difficult for me since my grasp of those details is not as good. I did try to mention each of the extinction events, but I didn't realize that the causes for them were so well-established. I don't want to get into too much detail since that section is already quite long, but I will look to expand it. I definitely do want to include more information about climate changes; hopefully you can keep an eye on my progress and suggest any material I haven't already included. — Knowledge Seeker দ 06:08, 17 April 2006 (UTC)

You're right: the restructuring would be only that one section. I think the supercontinents and/or mass extinctions form a logical chronology to work around; but restructuring might be more work than it's worth, and the switch from biology-focused to geology-focused for one section might seem strange, anyway. Finding references could also be a problem. If I have some time, maybe I'll write an alternative version of that section, and we can compare. bcasterline t 12:31, 17 April 2006 (UTC)

I was wondering if a final section on the future of the earth would appropriate, such as the end of the world as the sun expands. I have not seen any real discussion of it on Wikipedia, other than perhaps end of planet Earth. --Stbalbach 03:14, 17 April 2006 (UTC)

It's a good idea, but I'm not sure how it would fit the flow of the article—it seems a bit out of place in a history article. I'm not even sure how much we could write without getting into too much speculation. Probably not more than a couple sentences: "Future: In five billion years, the Sun will likely expand into a red giant, destroying Earth or rendering it uninhabitable" or something like that. I think it's appropriate in the "See also", but I just don't think it fits here. See Talk:History of Earth/Archive 1#future. What do others think? — Knowledge Seeker দ 06:12, 17 April 2006 (UTC)

I've seen standard narratives of this nature, talking about when the oceans boil off, when life ends, etc.. laying out the general stages of how the planet will come to an end. I don't think it should discuss the future of humanity or civilization, which are covered in other articles. -- Stbalbach 13:56, 17 April 2006 (UTC)

This article is about Earth's history and should not include speculation on the future, especially since it's long already. I think Future of Earth would make an interesting article though. bcasterline t 15:53, 17 April 2006 (UTC)

KS: To head off a request for a reference on the recently inserted link between the Permo-Triassic extinction and flood basalt volcanic activity in Siberia I will put one here if you need it (Grard et al, 2005). I'd be happy to forward any pdfs to you if you think you would find them useful…the intro to the Siberian Traps paper has some well referenced data that you might like. In addition, if links between LIPs/flood basalts and extinctions are mentioned for one mass extinction, they should be mentioned for others. This should include links between Deccan Traps (India) basaltic activity and the K-T extinction, reference below (Wingall, 2001). There may be others...I'm not knowledgeable enough to know which are "good" correlations and which are not.

Grard, A., Francois, L.M., Dessert, C., Dupre, B., Godderis, Y. 2005. Basaltic volcanism and mass extinction at the Permo-Triassic boundary: Environmental impact and modeling of the global carbon cycle. Earth and Planetary Science Letters v.234 (1-2) 207-221. doi:10.1016/j.epsl.2005.02.027

Wingall, P.B. 2001. Large igneous provinces and mass extinctions. Earth-Science Reviews v.53 (1-2) 1-33. doi:10.1016/S0012-8252(00)00037-4

Rickert 04:10, 17 April 2006 (UTC)

Rickert, that's very helpful; I'll use it when I incorporate Bcasterline's suggestions above. — Knowledge Seeker দ 06:13, 17 April 2006 (UTC)

Couple issues there

• "As intelligence increased and language became more complex" - is there any evidence to suggest that human intelligence (whoever measured) has increased during the lifespan of Homo sapiens?
• The article seems to suggest that sedentary lifestyles followed the beginnings of agriculutre - weren't the Natufians sedentary H-G? Guettarda 12:50, 17 April 2006 (UTC)

Thanks, Guettarda. I removed the offending statement—I think it's left over from a previous version of the paragraph which I subsequently rewrote. If you can think of anything to add to the statement, feel free. I'll poke a bit into the agriculture/nomadic relationship, but the Natufians article notes that they were unusual in founding permanent settlements prior to developing agriculture. Or am I misunderstanding? — Knowledge Seeker দ 07:00, 13 May 2006 (UTC)

According to Jared Diamond, many (maybe most) groups of people were sedentary before they adopted agriculture. Not all societies made the change from hunter-gatherers to farmers in the same way or at the same time (or at all), though, so generalizing is difficult. -- bcasterline • talk 22:58, 30 May 2006 (UTC)

This article seems to be more about the subset "history of life on earth", rather than the history of the planet itself. I would have expected more than a paragraph or two on the geological development of the planet. Think about moving the title to History of life on Earth, or even History of evolution on Earth, and creating an article more focused on the history of Earth related to the physical sciences (including geology, oceanography, history of the atmosphere, near-earth environment (origin of moon from earth), etc. from the scattered articles on these topics) for the History of Earth title. . --Blainster 21:59, 23 May 2006 (UTC)

Earth is used both in a literal and metonymical sense. (For instance, History of Europe does not mention its separation from Laurasia, not to mention its prior incorporation in Pangaea, and so on.) I have tried to weave together themes from all periods of Earth's history; the origin of the moon and the oceans and such occurred relatively early in Earth's history and I have been trying my best not to let the article become too unbalanced. I'd be happy to add (or have added) information on the geological development, particularly if good references are available, and as you can see above, I'm working to add more information on climate and geological change. In my opinion, "history of life on Earth" or "history of evolution on Earth" would be poor titles for the article—the formation of Earth, origin of the moon, formation of the oceans, and so on, have little to do with the history of evolution on Earth—though I welcome others' opinions as well. — Knowledge Seeker দ 22:40, 23 May 2006 (UTC)

Consolidating all information into one article is the easiest for readers, and the title "History of Earth" makes the most sense. But, it's also true that, after "The Hadean", this article focuses on biology and mentions geology and climate only marginally. (As has been mentioned before.) One solution would be to add more information on geology and climate, but the article is long already. So, creating three separate articles would also work: History of Earth for geology, History of climate for climate, and History of life on Earth for life. Note, however, that there is already a History of life without prose. -- bcasterline • talk 23:11, 23 May 2006 (UTC)

In writing this article, my explicit aim has been to try to synthesize a narrative from numerous disciplines. I would be quite pleased if someone were to write subarticles for specific disciplines and I would be especially pleased if anyone is able to offer assistance in integrating climate and geological information into the article, but I would prefer this article to remain an overview, and to have articles with a narrower scope written separately. — Knowledge Seeker দ 02:50, 24 May 2006 (UTC)

OK, I thought it over, and will withdraw the suggestion for a title change which (in my opinion) better fits the present state of the article, and propose expansion instead. I agree that the subject History of Earth is so broad that it must be a survey article with links to other main articles. The current article is nicely written. It just seems that it is too heavily oriented towards History of Life. This seems like the right title to bring several more topics together. Part of the problem is that some of the missing pieces are only sections of articles, and others are not written yet. By adding appropriate links to the topics I mentioned in the first post, you can see some examples. Bcaster points out the importance of climate history, and I should have mentioned glaciation as well. With this in mind, I will start a new talk section to discuss suggested organization and expansion. --Blainster 05:00, 24 May 2006 (UTC)

Mentioning that one theory is supported by the majority of scientists really gives no information at all (other than sociological) and seems to serve here to deprecate a minority theory. As hindsight shows us that nearly every dearly held conviction is eventually proven wrong, I would like to see wikipedia avoid this type of rhetoric and simply provide evidence (if there is any) and arguments to contrast theories. Brallan 09:01, 16 November 2006 (UTC)

The article Earth science offers an outline summarized in Earth's spheres, that could be a model for expansion of History of Earth, that is, to provide sections for each of the four spheres, beginning with the lithosphere following the cooling of the earth's crust. It looks like most of this would fit between the sections on the Hadean period and the Origin of Life (even though a good share of it is contemporaneous).

• Lithosphere
  • existing articles: historical geology, geologic time scale and geochronology
• Hydrosphere
  • paleoceanography, marine geology
• Atmosphere
  • Earth's atmosphere#The evolution of the Earth's atmosphere
  • paleoclimatology involves both atmosphere and hydrosphere, and the group including Ice age, glaciation, and glaciology
• Biosphere (already well covered)
  • paleontology, geoarchaeology

Hopefully this will inspire ideas for creating stub sections that link to other fields of Earth history not yet included. I am not necessarily suggesting that the "spheres" be used in section titles, just that the topics be covered. --Blainster 05:00, 24 May 2006 (UTC)

How about mentioning supervolcanic eruptions at Lake Toba and Yellowstone, formation of Hawaii islands, Himalayas, Great Rift Valley, Grand Canyon, Berring Straits and Arizona's impact crater, Tunguska incident, formation of fossil fuel, historical record of temperature and sea levels, earth's magnetic fields, precession( Milankovitch cycles) and rate of spin, change of vegetation in Sahara and Ethiopia? —The preceding unsigned comment was added by 203.116.34.138 (talk • contribs) 20:03, May 28, 2006 (UTC)

These are some good ideas, and I'll work to try to include some when I get a chance; I'm a bit busy right now. What would especially help would be referenced material—I really want this article to be well-referenced. Peer-reviewed journals, major books, or even authoritative web pages would be useful. — Knowledge Seeker দ 04:22, 15 June 2006 (UTC)

The analogy of the formation of Earth between geologic time and a 24 hour clock face is very confusing. Understanding large amounts of time is no more difficult than this analogy is. Should we remove it? Astrobayes 02:48, 8 July 2006 (UTC)

Well, since I incorporated the analogy when I wrote this article, I obviously think it's a good idea. Having the day analogy helps me to see just how recent in Earth's history the 380-million-year-ago emergence of the tetrapods or the couple-hundred-millennia-ago evolution of Homo sapiens is. But perhaps I am alone in perceiving this benefit. Also, I guess I don't understand how the clock analogy is confusing. Perhaps if you explain, I could clarify the article. — Knowledge Seeker দ 02:58, 8 July 2006 (UTC)

What makes the clock analogy confusing is that I have taken the time to understand and become quite comfortable with all scales of times and numbers - it isn't easy but it is definately worth doing since you can really appreciate the physical processes taking place in physical systems when such scales are involved. So, having become very comfortable with billions, millions, etc. it is quite unnatural to compare geologic time with clock time and in fact is a detriment to the education of individuals on such a subject. For example, when you're in chemistry class, calculating the number of moles in a volume of some sample the instructor does not dilute the concepts by making such numbers as 10^23 more palatable through an analogy to something "more familiar" to a general audience. Since Wikipedia aims to be encyclopedic it is therefore wiser to present the geologic time as a scientist would, and let the readers take the time to understand and appreciate such timescales rather than using an analogy that a scientist would not (in fact, a length analogy would work better here, using the length of a meter stick to represent the time from the beginning of the Earth's formation until today - and I would happily do the calculations for this article using this particular analogy). That's my professional opinion. Finally, I commented on this article because I'm a physicist in the Wiki:Physics project and this article was listed for request of peer-review. So, I'm offering to the editors of this article my professional peer-review: the clock analogy is confusing, not used by scientists, and so therefore should not be included in this encyclopedic article. Cheers, Astrobayes 03:13, 8 July 2006 (UTC)

I also disagree. The clock is an aid -- it's not used in stead of geologic time (so many years ago), it's used in addition to it. I think the clock analogy is fairly common and, to me, makes a lot more sense than comparing time to length, or anything else. I don't see how it hurts those familiar with geologic time (myself included), but I see how it could help someone who's not. -- bcasterline • talk 03:40, 8 July 2006 (UTC)

I know this was a little while ago, but I think the clock analogy is a good idea. As I was recently reminded by one kind Wikipedian, not every one has recieved higher education and for many people concepts which are simple and obvious to us are confusing or simply meaningless. I, also, am used to thinking in time-scales of millions and billions of years, but for many people such massive numbers are meaningless, in the same way that the size of this planet is meaningless when you never see it from above- see how vast the world is and how tiny we are. Wikipedia is as much for newcomers to subjects as for proffessionals, and the analogy does neatly put things into perspective. Weenerbunny 09:42, 12 August 2006 (UTC)

But there is another analogy which accomplishes the same goal, just as neatly, and doesn't use a scale of the same physical dimension (i.e. using seconds to represent billions of years - which is just completely awkward). I propose that we use a simple meter stick rather than a clock - in fact this is how many students first learn to deal with geologic time. In this case, we're dealing with small segments of the meter stick representing billions of years, and not seconds representing billions of years. And as geologic time progresses, we trace the meter stick from left to right. here's an example, and here's another, and another. In fact, the article on Geologic Time does just this. So why would the present article use a completely different analogy than the main article on the topic uses? That's a bit inconsistent isn't it?

And one final note, has anyone actually sat down and done the calculation for the time conversion in this article to see if the original author's scale is consistent? My guess is probably not. My guess is that everyone just reads the article and nods their head, taking all the numbers for granted when in fact the numbers are not consistent with a constant time conversion. And if the conversion is inconsistent then isn't using "clock time" as an analogy for geologic time rather a poor choice? My concern is simply that in a desire to present something "easy" or "digestible" we've accepted something that doesn't consistently represent the process. I'd like to go with the meter stick analogy, but if we keep the clock analogy we need to verify the math - no source for the calculations is cited. Your thoughts? Astrobayes 01:45, 19 August 2006 (UTC)

The clock analogy is the same as it appears on the National Geographic Channel on several programs on the history of the earth, which I would assume is reliable. Also I find the analogy to be excellent when explaining these things to people. It's easy to realize scales when you know the universe took 3 days to be created and human beings have been on earth for less than a second and dinosaurs lasted half a minute. Sabar 10:56, 21 August 2006 (UTC)

I don't particularly like the clock analogy either; it feels like I'm being talked down to, and it intrudes in a lots of places. It also is a little weird to encounter it when you jump to a specific section; not everyone is going to be reading the entire article from start to finish. It is worthwhile to try to give people a sense of scale and an overall picture of events. Why not simply have a pie chart showing the various periods? I think much of the problem of comprehension is that some people have a harder time digesting numbers - whether that's millions of years or seconds on a clock. A graphic would be much more intuitive, I think. -- Beland 21:06, 4 September 2006 (UTC)

I agree that it is a bit intrusive, especially if you don't read the article from top to bottom - most people do not do this with most articles they come across, while a larger number of people *do* sit through an entire television program, which is why the clock analogy works so well on the Nat'l. Geographic channel, but is at the same time so cumbersome in what could be a great article like this. It is human nature to skim something for the most salient points, and it bears considering this when improving this article. I had not thought of the pie chart idea but that is a really good one, and one I would support. I also am a fan of the old classic "meter stick" idea. As Beland states, some people have trouble with numbers, whether or not they are large or small, but everyone has an intuition with a "pie chart" or a "meter stick." Just something to consider. Cheers, Astrobayes 18:35, 5 September 2006 (UTC)

• • I agree with Beland, I think the clock analogy is very bad. It's confusing mainly because no conversion factor is given, and it collapses the time period too much. "Our clock"? ON my clock, the earth formed 4.5 billion years ago, and no 12am is going to cut it. --Lucifer arma 05:30, 23 March 2007 (UTC)

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I think the clock analogy is perfectly clear: it is used extensively in many general texts, and employed by science journals like Scientific American all the time. Are they all guilty of being "confusing"? I can't understand Astrobayes' reasoning. On the one hand, it is "confusing" to break down unthinkable eons of time into segments of something we all experience - a day - but then he does not feel any need to make material easier for non-experts - it's up to them to buckle down and digest the technical stuff. An encyclopedia is a GENERAL reference book, not a text for specialists. Let's remember who is looking up Wikipedia, and write for them, instead of showing off for our peers. There is just far too much of this in Wikipedia. The expert or would-be expert has a mountain of scholarly articles available to them, and they know where to find it. The average person is not so lucky. To write cogently and clearly for the non-specialist is much more of a challenge than just spraying technical material everywhere, most of which a lay person does not require in order to understand a subject. Please consider why it is that professional writers for journals like Scientific American and New Scientist can provide information on cutting edge science that is accessible by ordinary readers, while the "People's Encyclopedia" is riddled with obscurantist tracts that presume that the reader has a college degree in a subject, or at least should be aiming for one if they have the temerity to be reading about it. I have spent 20 years writing and editing technical material intended for non-professional users. Frankly, the biggest headache I had were "experts" on board trying to preserve the cachet of their subject by insisting on the inclusion of technical minutiae by the score. They would have been exactly the sort of people who fought tooth and nail to keep academic writings in Latin during the Middle Ages, and I would have paid good money to have them off any project I was on. abzorba 10:16, 2 October 2006 (UTC)

It is of course a matter of preference. I have stated my case for using a meter stick rather than a clock but if the marjority of readers find the clock analogy works well, I am certainly in favor of keeping it the way it is. The accessibility of this article is a huge concern, and the clock analogy doesn't change the content or science in the article itself, so if it works... it works :) Cheers, Astrobayes 23:20, 2 October 2006 (UTC)

A timeline would be more appropriate for this article. If you add a timeline as a graphic aid the flow of the text won't be interrupted with this analogy and you won't be confusing readers who haven't read the introductory paragraph. When I first read this I thought the page had been vandalized and someone had put exact times next to the pre-historic dates as a joke. Please explain how this confusion is better than simply providing a timeline. Jagget mcfew 04:39, 9 November 2006 (UTC)

There are several reasons I selected the clock analogy over a timeline. It is difficult to portray the entire range of events on a single timeline; many events happen during the last few million years. It is not possible to show them all. The way this is usually circumvented is by either showing a logarithmic scale, or by using a series of timelines with successively narrower ranges. Both are useful approaches, but what my intent is in this article is to really give people a feel for the time spacing of these events. I have no objections to someone creating and adding a timeline, and perhaps that will help some people see this better. But for people like me, and those I consulted when I began writing this article, changing the scale of time to reduce it to an interval the brain can easily grasp lets us see the temporal relationships in a way that timelines can't. There are several timelines on Wikipedia, and if you like, I can place notices to them at the beginning of the article. But I feel that this scale reduction helps make this material accessible for people who perhaps are not as well-versed in mathematics and the sciences as many Wikipedia are, and that's why I wish it to stay. — Knowledge Seeker দ 05:40, 23 March 2007 (UTC)

I don't want to beat a dead horse here.. but I was about to remove the clock references because I thought it was vandalism, fortunately I checked the history to see why it was there. Not everybody reads the entire article, I went down to something relevant in the middle of the article that I was looking for, and did not bother reading the first paragraph where you explained the "clock analogy" until I spotted what I thought was vandalism. This is not uncommon. I thought someone was being a smartarse and saying "oh it happened 38 billion years ago at 12:30am". I think this should be re-thought out. Let's summarize the "events" in a simple chart to find out how many data points we need. From there we can all get together and come up with a solution. I know you meant well, but I'm a smart guy, and it confused the hell out of me. I do like the concept of "putting things into perspective" due to the mass amount of time span between events, this just might not be the right way. 69.119.13.218 15:53, 27 April 2007 (UTC)

This is one of the best articles I've ever read on Wikipedia - kudos to the writers. The analogy is absolutely fantastic, and the tone of the article is perfect for understanding. — Deckiller 06:08, 20 September 2006 (UTC)

Was there a request for Peer Review of this article? Are editors still interested? If so, put a note on my user page and I will be glad to do it. I have a background in geology and marine biology, but currently study paleobotany and plant systematics. KP Botany 23:02, 17 December 2006 (UTC)

Why ask, instead of just looking at the article? (SEWilco 05:33, 18 December 2006 (UTC))

As I posted on your talk page, other articles requesting Peer Review had boxes on their talk page mentioning this--this page does not. If someone has already done it, there's no need for me to. Critically PRing a science article takes a lot of time. KP Botany 16:27, 18 December 2006 (UTC)

Echoing earlier comments, I think the basic material presented here is quite good and gives a nice synopsis of the origin of the planet and the subsequent evolution of life on the planet. BUT... it does not really address the guts of what most professionals think of as Earth History. Earth History includes the origin and evolution of life (after all, evolution is an observed fact of the fossil record -- Darwin just came up with an explanation for how it happens). But a great deal of earth history involves the formation of continents and their movements, the super continent cycle (eg Pannonia, Rodinia, Pangea), atmospheric evolution and its effect on geochemical cycles, the snowball earth hypothesis, global glaciations (Neoproterozoic, Permian, Pleistocene), and more.

I agree with other comments that the article is too long to go into all of these issues in detail, but the balance issue needs to be addressed -- especially since many of them relate directly to evolution of life on earth (e.g., links between early life, oxygenation of the atmosphere, and the formation of banded iron formations, or Pleistocene glaciations and the rise of modern homo sapiens). And anyone looking here for a real history of the earth will be dissappointed.

IF people do not feel that separate ariticles on Earth History (Biologic evolution) and Earth History (Geologic) are the way to go, then i suggest augmenting the current article with brief discussion of the major geologic aeons (Hadean, Proterozoic, Phanerozoic) inserted at the appropriate point in the evolution of life discussion. Thus, eariest cells after Hadean discussion, the Proterozoic discussion followed by rise of eukaryotes, the Phanerozoic discussion followed by complex life. Super continents were all mostly Proterozoic except Pangaea. Snowball earth was late Proterozoic, and the connections between impacts/large igneous provinces are all Phanerozoic. This will preserve the timeline approach that works so well in current article.

To save space, many of these issues can be alluded to briefly with link to whatever articles discuss in more detail.

I will think about this and await feedback from others. I have some other stuff i am working on now and see no need to hurry on this. Geodoc 04:04, 23 January 2007 (UTC)

This article is about past geologic events. See Earth for links to articles about the planet (including this article). See Biology for links to articles about biology (including History of biology. (SEWilco 17:28, 23 January 2007 (UTC))

Everything I discuss refers to past geologic events. Hadean = 3.8-4.5 Ga, Proterozoic 3.8-0.5 Ga, Phanerozoic 0.5-now. So this comment is puzzling. Geodoc 02:46, 24 January 2007 (UTC)

Please feel free to augment the article with additional information on Earth's geologic changes. I put in what I could when I wrote this article, but I am limited by knowledge, which is limited mostly to biological changes. As I have commented above, I would appreciate some integration of geological and climatological changes into the article. — Knowledge Seeker দ 17:42, 19 March 2007 (UTC)

This article is almost entirely about life. I think that is is rather biased. Of course as living organisms we have a tendency to me more interested in those things that pertain to us, but a history of civilization textbook should not be three fourths information about the cold war... even if it was written during the cold war. —Preceding unsigned comment added by 75.185.244.133 (talk) 03:16, 7 February 2008 (UTC)

It's not just a matter of interest... It is possible, and indeed very probable, that there is also much more information about the history of living organisations than about the history of the Earth before life. Just an assumption. Waltham, The Duke of 00:38, 11 June 2008 (UTC)

Please see History of the world as mentioned in the hatnote. You can question why the namespace is divided in just this way, and why these two articles have these two particular names, and I have questioned it myself without being able to think of any significant improvement, but we need to divide the material into these two articles because both articles are already very long as it is. (See WP:Article size.) The names chosen are based on questions of usage, I guess. And by the way, there's also a nice long article on geologic timescale. --arkuat (talk) 04:16, 24 October 2008 (UTC)

I agree, this article needs much more information avout (and references to) geologic history, such as the formation of various continents. There is lots of information about that, and it has nothing to do with the history of the (human) world. -Pgan002 (talk) 08:03, 18 February 2009 (UTC)

This has come up a few times lately with a few different people. Can we do something to prevent them from doing it? Wikidan829 16:49, 30 April 2007 (UTC)

I don't think there is anything preventative that could be done. People will vandalize wiki pages, for whatever reason. I think we just have to keep reverting bad edits where we find them, whether it be a creationist opinion on this page or a "john is gay ololololol" on another Aristeaus 08:35, 5 August 2007 (UTC)

just to remind the people editing this article that we must state that the text presented in this article is a theory. Although there is strong evidence supporting the text in this article, it is still a theory. We must present other theories to remain unbias. --Nat.tang 19:49, 2 May 2007 (UTC)

I agree. Anything is theory. The path of creationism should be mentioned - not in the same tone a recent editor did. A small section would suffice with a "see also" link to creationism. Wikidan829 14:15, 5 May 2007 (UTC)

Please see the second sentence of the article: "This article presents a broad overview, summarizing the leading scientific theories." Where there is scientific controversy or doubt, it is mentioned in the article. Creationism is not a theory in the scientific sense. Human origin beliefs and mythology are outside the scope of this article. — Knowledge Seeker দ 21:06, 5 May 2007 (UTC)

No, we cannot add a sentence in here that sets the article's scope in concrete, that's simply impossible. "History of Earth" is broad and it is clearly POV to limit it to scientific means. If this said History of Earth(scientific), that is a different story, but it doesn't. If it says "summarizing the leading scientific theories", then it should also say "for other stories"(generally) and link to creationism or other mythology. To do otherwise means this article does not meet NPOV guidelines. Wikidan829 21:45, 5 May 2007 (UTC)

Show me the scientific verifiability of any creation story and we'll include it. Until then, this is still an encyclopedia that pulls information from the mainstream of the scientific community. JHMM13 23:01, 29 May 2007 (UTC)

This is merely historical science, and thus, a theory. It should be treated as such to remain unbiased. It being accepted by the mainstream of the scientific community does not change that. As long as none of those from the mentioned community observed it, it cannot be placed in the same category as immediate, readily-testable science. This is not to say that the presenting theories are absolutely wrong; I'm not here to say that, and each person is able to make up their own mind regarding various interpretations. However, it is prudent that these articles be presented as intellectually honest as possible. Aglassonion (talk) 16:38, 20 February 2008 (UTC)

I'm intrigued by the remark that during the Hadean eon, Earth's radius was 40% of what it is now. I cannot find a reference on what made it increase to 100%. Can somebody clarify?--Robert van der Hoff 03:00, 3 May 2007 (UTC)

The same process that caused that radius to increase from 1% to 40%: Accretion of smaller bodies. :-) —The preceding unsigned comment was added by 24.180.185.247 (talk) 08:41, 10 May 2007 (UTC).

Makes sense. It makes me think that maybe continents got separated from each other because the Earth got larger, like a map on an inflated balloon, rather than just drifting around one a globe that is static in size. I cannot find a reference on the relation between globe size and formation of land masses.--Robert van der Hoff 14:28, 10 May 2007 (UTC)

Might it be possible that increase of the Earth's volume was not only caused by accretion of smaller bodies, but also by water absorption below the crust, like a sponge?--Robert van der Hoff 05:11, 11 May 2007 (UTC)

No, that's not a sound scientific theory. Btw see article on Expanding earth theory. Woodwalker (talk) 18:26, 26 February 2008 (UTC)

There has been a lot of back-and-forth on the appropriate format for this page, but it doesn't seem to have progressed much in the meantime. I'm not an expert in the field, just a knowledge seeker, but I support the view that this page should cover the physical History of Earth. Past, present, likely future, and some prediction about its end. (caused by our Sun, or collision with the Andromeda galaxy, whichever comes first). It could include some physical changes that people have made to our Earth, like the Panama Canal. If one needs to know about the History of Life, one should connect to another page. My two cents worth.--Robert van der Hoff 03:57, 7 May 2007 (UTC)

I noticed the caption on the image of a human in space talks about "one of Earth’s life forms broke free of the biosphere for the first", but when this happened it wasn't a person. Although not technically incorrect, isn't it really misleading having this caption on that image? Vicarious 07:26, 7 May 2007 (UTC)

Since my last post about this was ignored, I'm starting a fresh section at the bottom. I recently reverted an edit that removed all of the "clock" statements in the article. This isn't the first time this has happened, and I know exactly why. People come here for specific information, they do not read the entire article from top to bottom, which means most of them will miss why there are statements like "around 12:03 AM" on the page and pass it off as someone being a smartass. It is just further evidence to how confusing it is for someone who is not already familiar with this particular article. I'm going to aggregate a list of all the events that require a reference to the clock analogy, and propose a better way to handle this. If anyone has suggestions, please post. This clock thing just isn't working out. Wikidan829 13:22, 9 May 2007 (UTC)

Sorry, I know this is on my list of things to do, been busy in the real world. As far as the revert to get it back, I hope that it was done in good faith, and realizing that the person who removed them did it in good faith. The clock analogy does look like vandalism after all, especially since nobody reads every word of the article from top to bottom. Wikidan829 13:55, 25 May 2007 (UTC)

I think the clock analogy is great, but it kind of interrupts the flow of the narrative. I would suggest putting it in as a graphic sidebar, something like the timeline of the Big Bang.--Robert van der Hoff 00:17, 10 May 2007 (UTC)

The first sentence was modified by someone to make it clear that the origin of the Earth is unknown, when before it stated how it was in a matter-of-fact tone. I believe that stating it is a theory is more neutral and "safe". Thoughts and comments? Wikidan829 00:29, 15 May 2007 (UTC)

Seems like catering to other points of view to me. It's also theorized that God wished it into existence, but the article which the section introduces is the scientific explanation. — Someguy0830 (T | C) 02:58, 15 May 2007 (UTC)

Sure, it caters to other points of view, both religious and non-religious, that's what NPOV is all about. If we don't, then should we make it cater to a single point of view? All the addition does is admits that we do not know the answer, take it as you want. It's just a theory, amongst many. To say "the earth was created when" suggests that someone was actually there observing it, which is clearly not the case. If you want to find a deeper meaning than that, so be it, but there really isn't. Wikidan829 03:10, 15 May 2007 (UTC)

Not a particularly big deal, I suppose. ,"Estimate" might work better, considering the context. Never mind, forgot how it was written. — Someguy0830 (T | C) 03:35, 15 May 2007 (UTC)

"It may also have sped up Earth’s rotation and initiated the planet’s plate tectonics." = So plate tectonics could be a remnant of the sloshing of the Earth's crust that started when the Mars-sized planet grazed Earth? Author, how could this be further developed? I immediately thought of how Mars does not have plate tectonics...

I think that the clock analogy would be okay for a graphical timeline as someone else suggested, but I think it just adds clutter to the main text of the article. I think we should vote on removing it. Cheers, Rothery 08:43, 28 May 2007 (UTC).

Remove or keep...

Remove for reasons stated. Rothery 08:43, 28 May 2007 (UTC)

Remove --Nat Tang ^{talk to me! | Check on me! | Email Me!} 10:47, 28 May 2007 (UTC)

Remove Well it does have to go, there is no question about it, and I don't think a vote is necessary. We know the requirement and the issue. Nobody reads the entire article, so when they encounter one of the clock points, they think it is vandalism. Anybody here have photoshop skills? Wikidan829 14:28, 28 May 2007 (UTC)

Keep Now we have to change the article because of people's laziness? Joelito (talk) 22:20, 28 May 2007 (UTC)

People not reading the intro and not knowing about the clock analogy wasn't one one my reasons, but it is a valid one. Like it or not, people only read bits and peices, and it will just confuse them. Rothery 23:44, 28 May 2007 (UTC)

Again, when I write I do not have to be thinking about whether a person read the intro or not. You only have to be concerned about introducing a topic which will be explained in detail afterwards. In which case you add "see X below". Let's stop promoting laziness. Joelito (talk) 01:50, 29 May 2007 (UTC)

I have no idea what you're talking about. What is laziness? It's the fact that, out of context, the clock analogy looks like vandalism. Done deal. How does this "promote laziness"? Wikidan829 02:52, 29 May 2007 (UTC)

Whoever made this clock analogy to begin with meant well. The number of years makes it difficult to portray how far away the points in time were, but I don't think this is the solution to a problem where a timeline would suffice. I've said many times above that I'll do it, but I've just been too busy in real life. The whole reason I make this an issue is because the first time I saw it, I was going to revert it as vandalism. The only reason I didn't think it was, was because it was there for so long and nobody reverted it yet. I made it an issue once I saw other people actually remove them, on several occasions. This made it perfectly clear to me that I wasn't the only one to be confused by it. This article needs to be accessible and easy to read for anyone here. Wikidan829 02:59, 29 May 2007 (UTC)

Remove It is confusing for those not reading the entire article and unencyclopediac. It may have a place in a popular science article or a textbook but not an encyclopedia article.Rickert 00:13, 29 May 2007 (UTC)

Remove I don't like it, when I go to a specific spot it gets in the way and breaks the flow. I thought it was vandalism the first time I saw it. How about a clock anaology page. I know scientists like Bill Nye have used the ananology, mention that as a use in popular culture.

Remove I personally don't understand it, and I'm sure many others don't either. Plus the fact that it makes this sound like a narration, which it is not. 67.87.184.150 01:06, 5 June 2007 (UTC)

Remove After thinking about this for 24 hours, I decided the 11th hour might be approaching and it was best to not wait until the last minute to agree that the style doesn't seem to work very well here. I also keep stumbling over the gears of the clock more than finding the current time to be helpful. (SEWilco 01:39, 5 June 2007 (UTC))

lol! Great puns. I guess we have enough votes to remove it now- and not a second too late!... Sorry. I don't have time now, but if somebody else doesn't get to it, I'll remove it later. Rothery 02:35, 5 June 2007 (UTC)

The number of votes is not important -- the arguments raised are more important: Wikipedia is NOT a democracy. mike4ty4 21:46, 5 July 2007 (UTC)

True. But at any rate the arguments for removal easily outnumber and out...validify (you know what I mean) those (or the one) for keeping it. I keep meaning to remove it but haven't got around to it yet. I'll try to this weekend. Cheers, Rothery 21:26, 14 August 2007 (UTC).

Remove I have seen the analogy featured in many college level introductory biology textbooks; however, a ruler/meter stick analogy would more encyclopedic/scientific and easier to understand. Wikipedia articles are divided into sections so that users can reference exactly what they are looking for. Throwing this analogy in at points throughout the article breaks its flow and is very confusing for someone who just wants to look at one section. It is not laziness that may cause someone to skip sections, it is efficency and one of the great parts of wikipedia, being able to learn what you want to know without reading extraneous information. Anyways, all modern science and math tends to be done in base ten, why switch to multiples of 12 and 60 when explaining billons and millions?131.193.225.185 16:02, 6 June 2007 (UTC)

Maybe it should be modified. I didn't have a problem with it, but it might still be possible to save it. Why, first of all, would people get confused if the clock does not play a key role and one can simply ignore it and still understand the article? Perhaps it could be condensed into a small section of it's own called "Clock analogy" or something similar -- if it's a common enough thing in geology/earth science textbooks it might still worth a mention. I also do not understand how, say, a ruler would eliminate this supposed confusion either (it would just change the inserts from "8am on our clock" to, say "6 inches on our ruler" or something). mike4ty4 21:50, 5 July 2007 (UTC)

People find it confusing because when they read an article they don't read the entire thing, such as the intro. For example they might be interested in The Moon's section in this article and skip right to it. Since they didn't read the intro they will have no idea what the clock references are. They would be terribly confused by them and think they were vandalism. That is pretty much exactly what happened to me. I think the best way to 'modify' it would be to remove all the references and for someone to create a graphical timeline, possibly still using the clock analogy. If someone else doesn't, I'll give it a shot. Cheers, Rothery 21:26, 14 August 2007 (UTC)

Remove I don't like the clock analogy because it is "closed", in that when you get back to 12:00 you are "done". A linear time scale can easily go to "now" and then have an arrow or faded line to show that the "history" is continuing. I also agree with the previous comment "Anyways, all modern science and math tends to be done in base ten, why switch to multiples of 12 and 60 when explaining billons and millions?". That is a very good point. Not as bad as "furlongs per fortnight", but in the same league. The analog clock is something of an anachronism, isn't it? Myth America 07:14, 17 September 2007 (UTC)

The Life section introduces the "replicator" concept twice. —Preceding unsigned comment added by 66.90.166.35 (talk) 21:34, 6 October 2007 (UTC)

This is now corrected. -Pgan002 (talk) 07:42, 18 February 2009 (UTC)

I will put back my picture of the clock, not because I am in favour of a clock being used to represent geological time, but because the image gives the reader a comparative look at the length of major events and the different eons of Earth's history. If anyone objects please tell me here or on my talk page, and I will gladly adjust the figure. Personally I would not put a (linear) table with the geological time scale in this article, because such a table would be too large and because there are other articles (e.g. geological timescale) for that. Woodwalker 11:37, 19 October 2007 (UTC)

I will adjust the picture in a way it does not show clocktime (like 22:30 -> dinosaurs extinct). Woodwalker 11:42, 19 October 2007 (UTC)

Inquiry Article 'Complete Periodical Geological Time Table' Kvet 1990 GeoJournal 24.2 417-420. Article names 220M Geotectonic Cycles present to a 4870Ma date. I can find no further references to these 23 labels. Anybody have knowledge of this? —Preceding unsigned comment added by 76.171.57.120 (talk) 22:54, 3 November 2007 (UTC)

I’ve deleted complete crap about planets growing in size (like the universe), and denying the Pangean theory of tectonic drift. You know, you tube (and Superman comics) are not “citations”. And if this article were to include every “alternative” theory, it would be hundreds of pages long, and have to deal with underground mutants living in large cities, et al. Let’s stick to science, and that doesn’t mean that just because there is someone out there who is, in some capacity, a “scientist” and subscribes to whacky theories that it is legit to post his stuff into something that purports to be a scientific account of the history of the world. Go to Conservapedia. They love that sort of stuff up there. Myles325a (talk) 05:41, 7 March 2008 (UTC)

Wouldn't the inclusion of pseudoscientific gabblety junk as "an alternative theory" be considered vandalism?--Mr Fink (talk) 06:09, 7 March 2008 (UTC)

Since when was the League of Nations the "First Step" towards a world government?

I realize it lead to what may or may not become an eventual form of a "world government," but I don't recall it being an intentional step towards one as this article seems to suggest.

I've changed the section on the League of Nations and the UN. A World Government is synonyms with a "tyrannical empire" which I feel is bias towards institutions such as the UN and its predecessor the League of Nations. The goal of either is not to form a World Government now or eventually but to promote peace and open international communication. 99.240.36.63 (talk) 05:48, 25 April 2008 (UTC)

Yeah, I saw that... good catch on that sneaky bit of commentary and nice rewrite. And this has a good article banner? Aunt Entropy (talk) 15:46, 25 April 2008 (UTC)

I want to get a discussion going about the hatnote used in this article (and a couple of others). So you don't have to flick back, it's:

This article focuses on scientific information about the Earth. For religious beliefs about the Earth, see creation myth.

I've had a brief discussion with Ckatz, who argues that it discourages users from inserting religious material into the article. Honestly, I doubt it has any such effect. In my experience, almost all users who intentionally insert religious material into a scientific article, without discussion, are vandals and are unlikely to read the hatnote and have a change of heart. Just 10 minutes ago I reverted an instance of this at Universe. There are users who genuinely want to add religious beliefs to an article, and they almost always start a discussion first (sometimes a little harshly). At this point we note WP:WEIGHT as the reason the article takes a scientific POV. I really don't think a hatnote should be hiding this fact. Additionally, WP:HATNOTE explains we should be using hatnotes strictly as a disambiguation tool. Since disambiguation and points of view are totally different things, I think we should remove the above mentioned piece of the hatnote. Ben (talk) 00:40, 18 October 2008 (UTC)

The real question is, where does it stop? Should there be a note at the top of Big bang saying "This article is about the scientific theory of cosmogeny. For religious perspectives, see Creation myth." How about at the top of Universe: "This is about the universe as described by modern cosmology and astronomy, for religious perspectives, see Creation myth"? What about evolution? "This article is about the modern scientific explanation for the origin of species through the process of evolution by natural selection. For religious perspectives, see creationism." How about a standard template that we just slap on every scientific article that some biblical innerants are likely to disagree with? I suggest that someone clearly outline the intended scope of this hatnoting, and try to obtain consensus before implementing it. siℓℓy rabbit (talk) 01:08, 18 October 2008 (UTC)

FYI, per WP:BRD there was no good reason to remove the notes a second (or third) time after they were restored, especially given that they have been in place for months, and result from discussions at Earth and "Wikipedians against censorship". I wasn't the one who originally placed these, several other editors did so for a valid reason. Furthermore, WP:HATNOTE is a guideline, and as such should be interpreted "with common sense and the occasional exception." Whether or not it remains in the long run, this should have been properly discussed before removal so that others could have the chance to weigh in. --Ckatz^chat_spy 03:53, 18 October 2008 (UTC)

Excuse me? I did discuss the change after you reverted my bold edit. Since the change was across multiple pages, and you were the only one who reverted, I took it to your talk page. After a reply to your argument, I waited for over 24 hours for another response. Your contributions showed that you were active during this time, but I thought it would have been rude of me to demand a response and so I didn't chase you down for another, and just assumed you had nothing more to add. So please don't say there was no good reason to remove them a second time.

I have no idea why it's important who added the hatnotes (I certainly don't care), but with respect to the Earth discussion you mentioned, the consensus was to remove the hatnote, so I don't know why you brought it up. I do have a hard time imagining why the "valid reason" you gave was the result of a discussion at "Wikipedians against censorship", vandalism prevention seems a little out of their scope, but I'd be interested to see how it came about. Finally, can we stop quoting rules, guidelines and essays, noting what ones trump others and what to ignore, and instead get to the common sense bit you mentioned? There is a good reason mythology isn't included in these articles and a hatnote discouraging doing so is a bad reason. Editors should be aware of the good reason and not have to rely on the bad one. Vandals won't care either way. Ben (talk) 08:25, 18 October 2008 (UTC)

I agree with Ben, and the only place where this seems to have been discussed at all was at Talk:Earth where the clear consensus was to remove Creation myth from the note. There was also a discussion here (a rather inappropriate place for such a discussion, don't you think?) in which User:UrbanRose ultimately decided that the hatnote was "fine" (although I hardly consider her the arbiter of eternal consensus). Apparently then someone got carried away and thought that this meant there was a greenlight to add the notice to every article which religious zealots might disagree with. I think this is a good reason not to have the hatnote: it is just inviting some creationist POV-pusher to slap it onto everything under the sun. siℓℓy rabbit (talk) 15:00, 18 October 2008 (UTC)

The hatnote is entirely appropriate if a substantial proportion (Gallup Poll?) of the population disagrees with the 'scientific consensus'. The other alternatives would be either to incorporate religious beliefs within the article, or add links into 'see also' and Categories. ^rossnixon 01:15, 21 October 2008 (UTC)

Well, the US population isn't representative of the world, so the Gallup poll you mentioned (if it's the one I'm thinking of) is a useless argument for a worldwide website. I'd be happy to see a worldwide statistic that shows the majority of the world disagree with the article though, so please present your evidence.

Supposing you can't find a reliable source for your claim, I don't think hatnotes should be used to direct POV traffic. If an article doesn't correspond with your own beliefs, that doesn't entitle you to a hatnote. We simply report what the reliable sources report with respect to the articles topic, and that isn't religious beliefs, so your second suggestion is out too. If you can find a reliable source supporting your claim, then I guess we could report the statistic in the article (which will then link to corresponding set of beliefs, in this case creation myths, via a wikilink). Let us know how you go ... Ben (talk) 04:34, 21 October 2008 (UTC)

Indeed, hatnotes on articles are pretty much entirely for the purposes of disambiguation. One has to ask, even if a reader belonged to the group of people who believed that the Earth was created recently, is it likely that this person would come to this article expecting to find out about Adam and Eve and so forth. I think the answer is, resoundingly no. The person would go to Genesis or Creation according to Genesis, or other more targeted article. siℓℓy rabbit (talk) 12:30, 21 October 2008 (UTC)

Gallup Polls will be a "useful" indication for native English speakers. Although these are 'US only' polls representing 305 million people, there are only 375 million native English speakers in the world. Any 'large' US vote is not going to suddenly be diluted into a fringe view by the addition of the remaining 70 million potential readers of en-Wikipedia. ^rossnixon 02:19, 23 October 2008 (UTC)

I'm confused. Forgetting for a second that you didn't bring any reliable sources to the discussion for us to check, what does a person's native language have to do with this? This encyclopedia doesn't reflect what English speakin folk think, it reflects what reliable sources report. Your original research tacked onto a particular source doesn't count as a reliable source I'm afraid, and since you haven't brought any reliable sources to the discussion that conclude the majority of the world disagrees with the article, I don't see how you've made any ground in getting creation myths mentioned here. At best we could say that the popular opinion of x% of people of a particular country disagree with this article, but really, it seems a little peripheral for this article don't you think? Ben (talk) 02:49, 23 October 2008 (UTC)

Gallup Polls are often referenced in the mass media as a reliable and objective measure of public opinion. ^rossnixon 01:14, 24 October 2008 (UTC)

At best we could say that the popular opinion of x% of people of a particular country disagree with this article, but really, it seems a little peripheral for this article don't you think? Ben (talk) 04:16, 24 October 2008 (UTC)

Yes.Babakathy (talk) 06:32, 24 October 2008 (UTC)

I started a discussion at Talk:Age of the Earth about moving that article to 'Age of Earth'. The full discussion is there so I won't go into details, but the consensus was that 'Age of the Earth' was better, and so it stayed. The reasons given in that discussion for keeping the article where it is should apply to this article as well (as far as I can see), so should we move this article to 'History of the Earth'? Cheers, Ben (talk) 00:35, 13 November 2008 (UTC)

I support the name change. "History of the Earth" reads better and is unambiguous. "History of the Earth" gets 12,000 scholar ghits, versus 5,950 for "History of Earth". (In addition, the latter is often part of a phrase, such as "history of Earth's rotation", &c.) Thanks.—RJH (talk) 16:20, 13 November 2008 (UTC)

Support - this sounds like a logical change. Woodwalker (talk) 18:56, 13 November 2008 (UTC)

Does anyone think that the Snowball Earth theory is notable enough to add to this article, or is there not enough evidence to support it. Please comment.JakeH07 (talk) 04:06, 5 January 2009 (UTC)

It's already in the article. -- SEWilco (talk) 05:39, 5 January 2009 (UTC)

The Section "Cells" begins:

Modern life has its replicating material packaged inside a cellular membrane. It is easier to understand the origin of the cell membrane than the origin of the replicator, because a cell membrane is made of phospholipid molecules which often form a bilayer spontaneously when placed in water. Under certain conditions, many such spheres can be formed (see “The bubble theory”).^[1]: 40

(Emphasis added.) The "spheres" idea needs an introduction. What are these spheres? How do we believe they formed? How do we believe phospholipids formed? Also, the link Origin of life#Bubble Theory is broken and it is not clear where it should point. -Pgan002 (talk) 06:51, 18 February 2009 (UTC)

About the origin of mitochondria, the article says: "... a stable symbiosis developed between the large cell and the smaller cells inside it." Should that be "between the descendants of the large cell and the population of smaller cells inside them"? -Pgan002 (talk) 07:30, 18 February 2009 (UTC)

Creating a lead section for this article is a challenge, especially for a non-native speaker of English. But the article needs one, and I offer the following draft, taken primarily from the Danish edition of the article, to be subjected to heavy improvements, modifications, and copy-editing:

"The history of the Earth is a summary of the most important events and fundamental stages in the development and evolution that has taken place on the planet Earth from its formation to the present. The age of the Earth is 4.5 billion years (4,540,000,000 years),^[2] corresponding approximately to one third of the age of the universe, and immense geological and biological changes and upheavals have occurred during that time span. Nearly all branches of natural science have contributed to the understanding of the main events of the Earth's past, and the leading, most current scientific theories are presented below.

The formation of the Earth and the simultaneous formation of the Sun and other bodies of the solar system resulted from the contraction of a solar nebula. The nebula developed into a protoplanetary disk with the Sun forming in its centre and the planets forming by accretion of material in orbit around it. The Earth was formed 10 million years after the beginning of contraction. Heat generated by impacts and contraction meant that it was totally molten, and a differentation took place, forming an inner core of the heaviest elements and a mantle and proto-crust of the lighter elements. Around this time the Moon was formed, possibly by a giant impact between the Earth and a smaller planet. The Earth was steadily cooling and acquired a solid crust that gave rise to the first continents. A major bombardment from icy meteorites and comets supplied the Earth with an enormous amount of water that created the oceans, while volcanic activity and water vapor created an atmosphere, devoid of oxygen. The continents floated on the molten mantle of the planet and through plate tectonics assembled into supercontinents that later broke up again, a process that has repeated itself several times during the passing of the billion of years.

Chemical reactions created organic molecules which interacted to create still more elaborate and complicated structures, and finally gave rise to a molecule that was able to create copies of itself. This abilitiy initiated the evolution and led to the creation of life. At first life started in the form of one-celled organisms but later multicellularity developed, and a major evolution was the process of photosynthesis which supplied oxygen to the atmosphere and led to the creation of an ozone layer. The life forms branched into many species and became still more advanced, colonizing the land and gradually filling all the habitats of the Earth. Ice ages, volcanic eruptions, and major impacts of meteorites have caused several mass extinctions of life forms, but the remaining species have developed in new directions and have created a lasting biosphere.

About six million years ago, a split of branches of what was then the evolutionary family tree ultimately led to the modern man. The ability to walk upright, an increase in brain size, and improvement of communication skills were crucial factors. Man learned to control fire, developed agriculture and began systematic husbandry of animals and plants. This improved living conditions and societies and civilizations with religious and cultural characteristics formed. Through progress in science, writing, organization of governments, transportation and communication, man has become the dominant species on Earth and influences the environment and all other life forms. The scope of human activity and an increasing population now require mankind to apply a global perspective on major concerns and problems like protection of the environment, exploitation of natural resources, protection of wildlife, and climate change."

Maybe a sub-page dedicated to the discussion of the content of the lead sections would be an advantage? Regards, --Sir48 (talk) 23:53, 15 March 2009 (UTC)

Hi, I pasted this proposal into the article. I think it is a little too long for a header, but it will do for now.

For the coming months I will try to improve the article into something more geochronologically worthwhile. Chapters on many important things (palaeoclimates, orogenies, dinosaurs...) are still missing, while others (origin of life, development of cells and multicellular life, human civilisation) are too long. The problem is thus that the article is written too much from a biologic POV, that has to change in a broader, geochronologic POV. We already have evolutionary history of life for the biologic POV.

I put the section "origin of the Solar System" back under the Hadean and Archaean paragraph. As far as I know, it falls under the Hadean eon. Even if not, I don't think we should create independent paragraphs on topics that are slightly off-topic. This article is about the history of the Earth, not cosmology. Woodwalker (talk) 10:52, 17 March 2009 (UTC)

I do not like the 'about' in the second paragraph. The reference says it is know to a 1% uncertainty (45 million). For now I will remove the 'about' and simply have it read that the Earth is 4.5 billion years old. If someone can come up with some simple wording that demostrates the error it would be good. ie. between x and y years old, or 4.5 billion plus/minus 45million.--114.76.63.136 (talk) 13:13, 24 May 2009 (UTC)

This discussion is transcluded from Talk:History of the Earth/GA1. The edit link for this section can be used to add comments to the reassessment.

GA review – see WP:WIAGA for criteria

This review is part of Wikipedia:WikiProject Good articles/Project quality task force/Sweeps, a project devoted to re-reviewing Good Articles listed before August 26, 2007.

1. Is it reasonably well written?

   A. Prose quality:  

   We generally don't refer to ourselves when writing about a subject (MOS:BEGIN). "The history of the Earth is a summary..." and " It covers the leading, most current scientific theories and.." should be changed to a more natural presentation of the subject. Such as: "The history of the Earth spans geologic history, the evolution of life, and modern civilization..." Referring to the article itself is generally avoided.

   B. MoS compliance:  

   Introduction is a good length (WP:LEAD). Some of the redlinks could be changed to bluelinked articles, such as "outer asteroid belt", which is covered in "asteroid belt" (WP:REDLINK). Prolific overlinking (WP:OVERLINK).

2. Is it factually accurate and verifiable?

   A. References to sources:  

   Some references are provided.

   B. Citation of reliable sources where necessary:  

   This is where the article is really lacking. Long captions are ok, but there is a {{cn}} template in one of them, and probably belongs on all of them. The body is mostly cited, but there are some sections which lack cites entirely. Many of the links are also dead.

   C. No original research:  

   Unsourced statements may contain original research.

3. Is it broad in its coverage?

   A. Major aspects:  

   B. Focused:  

   This is the strong point, IMO. Article goes into detail without getting off topic.

4. Is it neutral?

   Fair representation without bias:  

5. Is it stable?

   No edit wars, etc:  

6. Does it contain images to illustrate the topic?

   A. Images are copyright tagged, and non-free images have fair use rationales:  

   B. Images are provided where possible and appropriate, with suitable captions:  

   Images are also great quality. Could use some trimming on the captions, and better placement.

7. Overall:

   Pass or Fail:  

   Article will be placed on hold until issues 1a and 2b can be addressed, 1b is optional. If an editor does not express interest in addressing these issues within seven days, the article will be delisted and reassessed as B class. --ErgoSum•talk•trib 17:37, 28 June 2009 (UTC)

After 7 days with no response, I have delisted this article. Feel free to renominate once these issues have been addressed. --ErgoSum•talk•trib 20:22, 5 July 2009 (UTC)

Hmmm. I've worked on the prose of the intro - I've not announced it here, though. --Stephan Schulz (talk) 20:34, 5 July 2009 (UTC)

Yeah I noticed, but I wasn't sure of your intentions. I thought you were just making driveby edits to the article, I checked the top contributors and your name wasn't there so I assumed you had no interest in making the kind of edits needed to improve this article. Its no big deal to renominate anyway, and who knows I might even review it again if that were to happen. --ErgoSum•talk•trib 21:02, 5 July 2009 (UTC)

You're not quite wrong - I came upon the article by accident, found your comments, and decided to fix a few. But I'll not handle everything on my own - I hope some more editors jump in. --Stephan Schulz (talk) 21:31, 5 July 2009 (UTC)

Overall, I think they improve the article. But in between them, they have completely gutted the Lede (well, CoM moved much of it to the body and Woodwalker then removed it as duplicated). Following WP:LEAD, the Lede should summarize the article and work as a stand-alone introduction to the topic. I would suggest to recover but further shorten some of the old lede. Any comments? --Stephan Schulz (talk) 12:12, 10 July 2009 (UTC)

I first need to write the sections about the Paleozoic, Mesozoic and Cenozoic before I can write an abstract. If I am finished writing the article I will rewrite the header completely. Meanwhile, Sir48's proposal was a nice header for the time being, though perhaps a little too long. Parts of the header were pasted into the main text, which they were already summarizing, creating a nasty duplication of information. It was a complete mess! It took me some time before I even understood what had been done, but when I did I tried at least to get the structure back in the article. Some small edits in between may have been lost with my drastic edit but I saw no other way. Someone who hasn't read the complete text and doesn't understand what it is about should not reshuffle large parts of it, cause this is really not improving the article and besides it's confusing for other editors and readers. Woodwalker (talk) 12:41, 11 July 2009 (UTC)

The faint young Sun paradox[1] isn't mentioned in this article. I think it would be good to include this for completeness. Thanks.—RJH (talk) 20:53, 27 July 2009 (UTC)

Added.—RJH (talk) 17:49, 16 January 2010 (UTC)

The text stated that Theia became unstable as the Earth increased in mass. Incorrect. The L4 and L5 points are stable when the masses of the two principle bodies are high compared to the third body; Theia's L4 spot became unstable as it's mass ratio to Earth increased - i.e., it mass increased faster than Earth's did. I changed "Earth" to "Theia", and cleared up the sentence following. In the following paragraph I added that the Theia hypothesis required that the collision occur at a relatively low velocity as well as at a grazing angle. Simulations I've seen used a velocity of 8 km/sec (18,000 miles/hr). 71.229.179.28 (talk) 21:05, 13 October 2009 (UTC)

In this sentence :

A small African ape living around six million years ago was the last animal whose descendants would include both modern humans and their closest relatives, the bonobos,

is a link to some music band instead of

http://en.wikipedia.org/wiki/Bonobo —Preceding unsigned comment added by 85.10.9.194 (talk) 12:56, 23 November 2009 (UTC)

The main Cenozoic issue (development and diversification of mammals) is included into the Cenozoic, whereas the Cenozoic section refers to human development and history. I propose putting the Cenozoic into the Cenozoic section and open a new section, e.g. "The development of humans" or so to cover human issues. These sections are really mixed up, I would let that fail in a GA review. --Eu-151 (talk) 08:55, 8 April 2010 (UTC)

If you use {{hat}} to close a discussion and hide it, don't forget to end that section with {{hab}}. Otherwise later discussion also gets hidden. Stfg (talk) 20:23, 4 May 2010 (UTC)

The article currently states that "When a process similar to present day plate tectonics did occur, this would have gone faster too." However, my understanding is that we don't actually know whether plate tectonics during this time period would have gone faster. For instance, increased temperature of the mantle might have led to decreased slab pull, which would have slowed down tectonics relative to today. There also may have been smaller plumes due to the greater viscosity of the mantle, which would have affected the speed of tectonics. Any thoughts on the matter? Palaeocastor (talk) 00:00, 18 May 2010 (UTC)

I found this source, which says, "recent paleomagnetic data indicate Archean plate motions may have been significantly faster than at present." But I think more sources are needed. Crum375 (talk) 00:56, 18 May 2010 (UTC)

The article states that "Because young volcanic crust is relatively hotter and less dense than old oceanic crust, the ocean floors will rise during such periods." As I understand it, this isn't really correct, or at least isn't complete: because the new oceanic crust is young, it hasn't had time to cool as much as the older crust, so it is less dense and thermally expanded (it takes up a greater volume when it is warm than when it is cold). Because it is thermally expanded, the young ocean floors stand higher than the older crust; that's why the mid-ocean ridges are higher. I think the way the article puts this now is misleading. I would fix this myself but I am a new user and don't yet have permission to edit this page ... Palaeocastor (talk) 00:27, 18 May 2010 (UTC)

I have reduced the protection so you should be able to edit. If renewed protection is needed, hopefully by then your account will be old enough. But please be sure to support anything you add or change with reliable sources. Please read WP:V, WP:SOURCES, and WP:NOR carefully. Crum375 (talk) 01:00, 18 May 2010 (UTC)

"As language became more complex, the ability to remember and communicate information resulted in a new replicator: the meme.[88] Ideas could be exchanged quickly and passed down the generations." Regarding this reference to Meme's in the Civilisation section. Memetics is still a fairly controversial subject, and I'm not sure there is enough of a scientific consensus about it to include it in the history of the Earth quite yet. Xmp (talk) 14:27, 13 July 2010 (UTC)

The term "meme" is only used here to convey the non-controversial notion that in the case of modern humans, information can be transmitted between generations via language and writing, in addition to purely genetic means. It is well sourced, to an expert in the field, and the controversial aspects are skirted. Crum375 (talk) 16:17, 13 July 2010 (UTC)

I'm not saying it's not well cited but I am suggesting that perhaps the term "meme" comes preloaded with Dawkin's hypothesis of memetic transmission and mutation attached. It is a nice model but it still doesn't merit the status of accepted theory which appears to be what this article is aiming for. Xmp (talk) 14:53, 21 July 2010 (UTC)

I agree that some aspects of "meme" are not yet universally accepted, but we only mention the part that is non-controversial, as I noted above. Also, this article is not strictly aiming for universally accepted theories, since many aspects of the history of the Earth lack clear consensus (e.g. the Moon's creation). It seems to me that the article simply describes the most common theories or hypotheses about the various aspects, and mentioning the meme makes sense within that framework. BTW, I am not the one who added it, but I think it does add perspective to the article, and provides food for thought. Crum375 (talk) 17:54, 21 July 2010 (UTC)

I do like this article, but its wording, in my opinion, is far too objective. None of us were around 4.6 billion years ago to witness this, and we can't absolutely prove that the earth is even that old. Sure, there is substantial evidence, but there is always doubt. I feel the article should be editted in a manner that does not shove these theories across as absolute, infallible truth, as this one very much seems to.Mwakin21 (talk) 21:39, 18 October 2010 (UTC)

It isn't possible to "absolutely prove" anything outside of mathematics and logic. A date of approximately 4.6 billion years is overwhelmingly accepted by the scientific community, and giving any other impression would be giving undue weight to a tiny-minority view. Editing the article to add a young-earth creationist viewpoint would violate Wikipedia policy. Hut 8.5 22:04, 18 October 2010 (UTC)

how the heck am i as a person without a degree in earth's history supposed to know what "ma" and "ga" means? could you please just change it to BC so normal people will be able to easily read this article? or just put an explanation section in the beginning of the article? — Preceding unsigned comment added by Someone35 (talk • contribs) 14:31, 17 August 2011 (UTC)

The terms are now linked to articles which explain them. We're not obliged to use "BC" since the terms "Ma" and "Ga" are commonly used in the relevant fields, "4.5 billion years BC" is a lot less concise than "4.5 Ga", and making a distinction about the 2000 years since the birth of Jesus implies false precision in the context of almost all the dates used. Hut 8.5 10:47, 18 August 2011 (UTC)

ok, thanks. but maybe "4.5 billion years ago" can be more simple for people to understand-- Someone35 (talk) 15:08, 18 August 2011 (UTC)