Talk:Fossils of the Burgess Shale

Possible structure

 * History of collection
 * Walcott
 * 1960s-1970s collecting and re-analysis (Alberto Simonetta, Desmond Collins, Whittington, etc.)
 * Still producing new taxa (Orthrozanclus, Hurdia) as well as more and better specimens of the known ones (esp Odontogriphus).
 * How the fossils were preserved
 * Brief outline of Burgess shale type preservation.
 * Slip the dating of the bed(s) in somewhere.
 * Summary of animals found (pref w numbers, a sort of census)
 * Notable fossil animals (usual suspects)
 * Theoretical significance ( preliminary Paleozoic pyrotechnics). --Philcha (talk) 20:24, 24 April 2009 (UTC)


 * That's a broader scope than I had anticipated - but I think it will work splendidly. Caron's recent palaeocommunity analysis should be a good source for the summary of animals found.  I'll bagsie that bullet point for starters. Martin  (Smith609 – Talk)  21:02, 24 April 2009 (UTC)


 * "a broader scope than I had anticipated"? I'd consider it seriously incomplete without any of these, and would fail it at GA ("broad coverage") if not remedied, never mind FA. --Philcha (talk)
 * I don't know Caron's recent palaeocommunity analysis, so you're better placed than me to do the "census" bit. I'd also say it's the highest priority, as we already have a ton of sources (and pastable text) for the rest, and covering the "usual suspects" w/o a census would probably cause loss of perspective. I think you've just put yourself in the firing line :-) --Philcha (talk) 22:10, 24 April 2009 (UTC)
 * Here it is...
 * Now to hope my weekend doesn't become as busy as it looks like it might... Martin  (Smith609 – Talk)  01:33, 25 April 2009 (UTC)

Scientific points
The article's looking very good so far - your writing style is very agreeable these days! I appreciate you re-writing my contributions into accessible English - I had taken the approach of getting the information in there in any form, with the intent of re-writing it later once it had taken shape a little.
 * I understand, I sometimes do the same, especially if the phone rings or the cat miaows. --Philcha (talk) 17:34, 28 April 2009 (UTC)

I thought I'd best give the rest of the piece a quick skim, although unfortunately I don't have time to do anything more than that. I picked up on a couple of scientific points:


 * There is now compelling evidence that the BS was oxygenated. Anoxia cannot account for the preservation
 * Burrowing is also present in the BS; I think there's a paper discussing burrowing at the Chengjiang, which shows both that things are oxic, and that the sediments were partially disturbed
 * OK, add it and the citations. I thought Caron & Jackson (2006; "Taphonomy") already made those points quite well. --Philcha (talk) 17:34, 28 April 2009 (UTC)


 * There is good evidence that the sediment was bound in places (I think microbes are the only suggested reason for this)
 * Go for it. Can we w-link to Cambrian substrate revolution as well as microbial mat? --Philcha (talk) 17:34, 28 April 2009 (UTC)


 * 'THE defining feature' of BS type pres - this def needs sourcing; I'm not sure there's agreement on a definition of BStp.
 * I thought Butterfield (2003) was spot on - and my impression is that this is not new, see Wonderful Life (1989 - not quite BCE, but ...). --Philcha (talk) 17:34, 28 April 2009 (UTC)


 * Odontogriphus was a shell-less mollusc and is preserved. (FWIW there are other unpublished shell-less molluscs in the BS.) There are in fact quite a few things which could be tweaked in this paragraph - perhaps I should take a look at it.
 * Does that mean you think the Halwaxiid debate has been settled? --Philcha (talk) 17:34, 28 April 2009 (UTC)
 * BTW has Butterfield published anything on this since Pal. Ass. 2007? --Philcha (talk) 17:38, 28 April 2009 (UTC)

Anyhow, I like the shape things are taking, and look forward to doing a bit more work on the article myself! In the meantime, do you think it's worth getting some publicity at did you know? We'd need to nominate it today (or tomorrow at the latest). Martin  (Smith609 – Talk)  16:35, 28 April 2009 (UTC)


 * That occurred to me, although the hook items I saw (Anomalocaris: The comedy, Aliens VI: Hallucigenia) did not seem to fit too well with the article's title. But if we can get away with using the title just as a link, not in the hook text, they would be good - unless you had something else in mind. --Philcha (talk) 17:34, 28 April 2009 (UTC)


 * Hiding the title behind a wikilink is fair game. Alternatively, we could go with something as broad as "The fossils of the Burgess Shale prompted a reinterpretation of the history of life" [or something a little more accurate].  (I'll address the other points anon.) Martin  (Smith609 – Talk)  19:41, 28 April 2009 (UTC)

List of critters
I think it's long enough - currently Marrella, Opabinia, Anomalocaris and Hallucigenia representing the panarthropods, which started all the fuss; Wiwaxia, Odontogriphus and Orthrozanclus representing lophotrochozoan victims of Wiwaxia War I; Canadia to show that fossils can be fun even if not involved in a phylogenetic phrenzy; chordates, well, you know why.

However any selection is going to be controversial - if you explain it, someone will grumble about "editorialising" (that happened at Talk:Evolutionary history of life/GA1); if you don't, someone will demand a big essay, with citations, on why this particular lot of critters is particularly notable. Would it be worthwhile listing all the documented Burgess critters and linking to it? I'm thinking of a table sortable on name, date discovered (Anomalocaris will be interesting), site where first found, classification (yes, that's a can of invertebrates) - plus non-sortable "Comments" column (or head it "Brief description" to ward off WP:zealots). See the results tables at Alexander_Alekhine for an idea of how it would look. --Philcha (talk) 09:08, 29 April 2009 (UTC)


 * I think that so long as the text itself makes clear why the critters we mention are particularly notable, we should be okay. I can't think of any other 'must-includes' and if anybody wants to suggest why we are lacking, let's hear them out.  No-one in their right minds is going to ask us to detail every single organism on this page, and I think that the current list is a great sample and fits the bill perfectly. Martin  (Smith609 – Talk)  14:13, 29 April 2009 (UTC)


 * None of the trilobites are mentioned except Tegopelte gigas in the references. It might be worth mentioned the major genera at least briefly, even if they're not as notable: Olenoides, Elrathia, etc. Maybe a list of ten or twelve? Metaknowledge (talk) 01:19, 28 March 2011 (UTC) --Philcha (talk) 17:21, 28 March 2011 (UTC)


 * There's not room for every phylum - e.g. the list excludes priapulids (Louisella), tardigrades, brachiopods, echinoderms; and excludes some puzzles, e.g. Iotuba chengjiangensis (was it a phoronid or a priapulid?), Lingulosacculus nuda (a phoronid or a brachiopod?). Arthropods are represented by Marrella, notable for not being a trilobite. --Philcha (talk) 08:06, 28 March 2011 (UTC)


 * Maybe what we need is to create another article that is simply a list, ordered by phylum, with notes as appropriate, in table format. Then there can be no qualms about not including stuff on this article, because less notable stuff still gets a mention as a member of the Burgess shale biota. Metaknowledge (talk) 15:22, 28 March 2011 (UTC)


 * My "to do" list is already quite long. If you fancy a go, your first priority would be getting citations. Fossils_of_the_Burgess_Shale could be a start - but only a start.


 * Actually, I'd love to do this, but I seem to be a little ignorant about this already - all I need as far as citations go would be proof that the organism was represented and then proof for any claims I make in the notes section, right? Or am I totally missing something? Metaknowledge (talk) 22:10, 28 March 2011 (UTC)


 * Or should we go for simplistic like List of Chengjiang Biota species by phylum? I was thinking a table with sections genus, phylum, and comments/notes, but that might be expansionist. By the way, there really should be articles for each of these genera, but I noticed three we already mentioned (Tegopelte, Iotuba, and Lingulosacculus) don't even have articles... maybe that's a greater priority. Metaknowledge (talk) 01:53, 29 March 2011 (UTC)


 * Making a list of genera / species of Burgess biota and doing it well would be a big job:
 * What about non-metazoa, e.g. plants?
 * What about trace fossils?
 * What about ones whose taxonomy is dubious? E.g. List of Chengjiang Biota species by phylum lists Iotuba chengjiangensis as a phoronid but it could be a priapulid (I can supply citations for Iotuba and Lingulosacculus).
 * What about citations? List of Chengjiang Biota species by phylum has none, but I'd expected them for dubious ones?
 * Articles about Burgess genera not already in WP may be a better approach (or easier!) if there are citations and if you can find or WP articles to link to the new articles, so that the new articles are not orphans. --Philcha (talk) 08:00, 29 March 2011 (UTC)


 * In response to points raised: as for non-eumetazoans, that's a big issue because I can't find a free, internet-accessible complete list of genera (not going to sweat about species for this) and while it looks like sponges are covered, I can't be sure of course, and plants, algae, etc are most definitely an problem.


 * I hadn't thought about trace fossils, but I wouldn't worry about that unless their creator is unknown... I don't know too much about them.


 * For classification debates, they will either be explained in the notes section or if they extend to the phylum level I would list them with slashes in order of support (no more than 3 or so).


 * I think I can find (a few) sources and the more dubious, the more debate, the more citations!


 * So, my final stance is that a list is a dealbreaker - I can deal with the other obstacles but not this one. If there is no list, I'll go back to article creation on the genus level. Metaknowledge (talk) 16:12, 29 March 2011 (UTC)

Orphaned references in Fossils of the Burgess Shale
I check pages listed in Category:Pages with incorrect ref formatting to try to fix reference errors. One of the things I do is look for content for orphaned references in wikilinked articles. I have found content for some of Fossils of the Burgess Shale's orphans, the problem is that I found more than one version. I can't determine which (if any) is correct for this article, so I am asking for a sentient editor to look it over and copy the correct ref content into this article.

Reference named "Caron2006": From Morania:  From Burgess Shale type preservation:  

I apologize if any of the above are effectively identical; I am just a simple computer program, so I can't determine whether minor differences are significant or not. AnomieBOT ⚡ 15:05, 30 April 2009 (UTC)

Preservation
I'm removing the "cn" tag as Butterfield 2003 (next sentence) covers this. From what I've seen FAC appears to dislike blue smallpox. If you think alternative defs of BS preservation need to be added, go for it - with citations, no maintenance tags, please. --Philcha (talk) 15:10, 30 April 2009 (UTC)

BTW you never did explain the "verification needed" tag you left in Mollusc over 6 months ago. --Philcha (talk) 15:10, 30 April 2009 (UTC)

"The elements of the organism with a high preservation potential are those constructed of recalcitrant carbonaceous compounds" is dubious and probably inaccurate, e.g. Wiwaxia sclerites are not mineralized, and chitin appears to be a major candidate for BS preservation. I'll sort that out. --Philcha (talk) 15:10, 30 April 2009 (UTC)
 * I've made tried to make this less jargon-laden and to avoid the "recalcitrant carbonaceous compounds" issue, see what you think. --Philcha (talk) 15:49, 30 April 2009 (UTC)

You may be right about "This pattern may sometimes help palaeontologists, by indicating whether a group of organisms could have fossilized in a particular type of fossil bed, or by suggesting whether a body part was fairly tough like an arthropod limb (preserved as flat film) or very soft like a part of the gut (preserved as a solid piece of mineral)" needing clarification - I'll leave the tag in for a while to make me think about it. --Philcha (talk) 15:10, 30 April 2009 (UTC)
 * I've tried to clarify how it helps, see what you think. --Philcha (talk) 15:49, 30 April 2009 (UTC)

BTW I agree w your HTML comment about Canadian dialect, and I'm sure your hosts would agree, as there's bit of nationalism around the BS - but you'll have to copyedit when the content is stable, as I have no idea of the subtle differences between US and Canadian usage, spelling etc. --Philcha (talk) 15:49, 30 April 2009 (UTC)


 * As far as I can tell, Canadian uses Englsih spelling [e.g. colour], but American words [e.g. railroad, sidewalk]. I'll give it a once over when necessary (and deal with the other points when I'm awake). Martin  (Smith609 – Talk)  21:34, 30 April 2009 (UTC)

I agree that "Beds may have subsequently been re-disturbed, and consequently may represent a 'time-averaged' community ..." (Caron & Jackson 2008) is a bit isolated. I didn't see in the source any explanation of how they might have been re-disturbed, what the evidence is, and how severe the re-disturbance can be (e.g. into the next higher burial layer). Have i missed something. --Philcha (talk) 16:42, 30 April 2009 (UTC)


 * It was probably me trying to qualify 'time-averaged' a bit - I think the term needs explaining, although I did a rather dire job. Other sources may be more useful? Martin  (Smith609 – Talk)  19:40, 4 May 2009 (UTC)
 * I interpreted "time-averaged" in Caron & Jackson (2008) as referring to the fossils that clearly ceased to be alive before the burial events - molts & dissociated body parts.
 * Do you have some memories of sources that mention re-working? --Philcha (talk) 20:47, 4 May 2009 (UTC)

The lagerstätten a pause for breath in the radiation of animals?
SCM (1986) says the BS represents a pause for breath in the radiation of animals, which temporarily accelerated again in the mid-Ordov. The Chengjiang fossils are as similar to the BS ones as you could expect with a 15 MY gap, implying that the CEX ended before about - but are there any sources for that? I don't know how much has been found at Sirius Passet or whether anyone's suggested how long that is after the actual end of the CEX. Can you fill in any of the gaps? --Philcha (talk) 07:57, 1 May 2009 (UTC)


 * 1986 was a long time ago... there is no real definition of the "explosion"; every author has his own ideas about it. There was certainly a radiation in the Ordovician, and things probably settled down in the Late Cambrian (perhaps this is an illusion caused by extinctions?), but diversity is still increasing in the Burgess (Caron 2008).  What we know is that there was nothing complicated in the mid-Ediacaran, and lots of complicated things by the Chengjiang, but we don't know much about in-between.  This means we can't really say whether the difference between CJ and BS was at the same rate as before-hand, or slower.  In 1986, understanding of the Ediacarans was limited, so it looked like everything appeared between the base of the Cambrian and the CJ - a relatively short time.  But if we include the preC 'fuse', suddenly the explosion looks less sharp.  I remember having a discussion with Graham Budd on these very pages where he derided any definition of the length of the explosion - so I think it's something best avoided! Martin  (Smith609 – Talk)  14:01, 1 May 2009 (UTC)

Stratigraphy
Here's the most up-to-date discussion on stratigraphy:

Significance
I've had a look at this section and I feel it's a little confused. It might help to lay out a structure for it - here's how I might modify your existing structure:


 * The traditional view is that animals appear from no-where at the base of the Cambrian. A few examples of why: SSF, sudden trilobites/echinoderms, poor stratigraphy.
 * No-body thought there was Precambrian life
 * Problems this caused: Darwin's confusion
 * Explosive interpretation
 * Gould's view on the BS as a post-explosion melange
 * Lots of phyla-from-nowhere


 * More recently, we have discovered:
 * Diverse Ediacaran biota (including modern phyla?)
 * Gradual increase in Cambrian complexity
 * Other Cambrian lagerstatte
 * How to classify oddballs


 * How is the BS significant now?
 * Potential of stem theory - relationships between modern groups, and their ancestral forms

Feel free to tweak as you please - if we agree on a structure it will make copy-editing each other a little easier. Martin  (Smith609 – Talk)  18:19, 5 May 2009 (UTC)


 * There's plenty of room for discussion - I was feeling my way through the sources, and trying to minimise the confusion caused by earlier discoveries that were dissed.
 * I've replicated your structure in order to comment:


 * The traditional view is that animals appear from no-where at the base of the Cambrian. A few examples of why: SSF, sudden trilobites/echinoderms, poor stratigraphy.
 * I'd prefer "pre-1950s view" to "traditional view" as it's more explicit and AFAIK accurate - you know the jokes about the meaning of "historic" in the USA. --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * By "poor stratigraphy" do you mean assigning Spriggs' finds to the Cambrian? --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * I was more referring to the poor resolution, which didn't let people work out how much relative time separated various beds, amplifying the sense of explosion. It's still difficult to correlate many strata today. Martin  (Smith609 – Talk)  20:35, 5 May 2009 (UTC)
 * Yes, see Aleksey's post and my response, which I've turned into a separate thread because it's a big subject in it's own right. I think it's a matter of presentation. For me the main significance of the BS fossils consists of: impact on bilaterian phylogeny; and challenges it presents to evolutionary theory. The latter is the easier to explain initially, and the natural headline for that is Darwin's comments; then explain the background (no preCm fossils in 1859; preCm fossils found 1868 onwards but dismissed, etc.)


 * No-body thought there was Precambrian life
 * Only after Seward's vociferous but mistaken denials from 1931 onwards. As far as I can see, Walcott's findings were accepted 1883-1931. I read through the whole sorry story in Schopf's article (PNAS) / chapter (Cradle of Life) and glossed over the details, as I thought things were going to get quite complex enough from the 1970s onwards. --Philcha (talk) 19:30, 5 May 2009 (UTC)


 * Problems this caused: Darwin's confusion
 * No, I think that's got to be the start-point, both because D (?)first formulated the problem and because the relevant finds occured entirely after the first edition of Origin and mostly after D's death in 1882. --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * Darwin's confusion doesn't make sense unless the reader knows that (1) he thought that life appeared suddenly at the base of the C; and (2) there was no evidence of PreC life at the time of OOS. Martin  (Smith609 – Talk)  20:35, 5 May 2009 (UTC)
 * I think your point (2) is matter of presentation - it's the diffence between (a) "There was no evidence of PreC life at the time of OOS, so D found the CEx a major difficulty for his theory"; and (b) "D found the CEx a major difficulty for his theory, because there was no evidence of PreC life at the time of OOS". I think (b) is a better headline, because we'll need to summarise the (mis-)interpretation of fossils 1868-1947 in order to set the context for Whittington & co's re-assessment of the BS fossils.
 * I think your "Darwin's confusion doesn't make sense unless the reader knows that (1) he thought that life appeared suddenly at the base of the C" is not quite right - D's response to the puzzle was to assume a long, cryptic history of life, see e.g. Origin_of_Species. --09:37, 7 May 2009 (UTC)


 * Explosive interpretation


 * Gould's view on the BS as a post-explosion melange
 * Lots of phyla-from-nowhere
 * I think omitting mention of the "long, cryptic" view makes it seem like the "explosive" interpretation was already unchallenged, in which case the BS fossils would have been much less important. --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * It's not specifically Gould's view, in the 1970s Whittington produced a phylo diagram often described as a "phylogenetic lawn", which IIRC Brysse reproduces (along with everyone else). Wonderful Life was out-of-date by the time it was published, because Briggs & Whittington published their first cladogram in 1981. --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * I'm not sure how BS says anything about the long, cryptic viewpoint. I'm trying not to get into details here, but perhaps you could outline what you think the BS contributed to the debate? (I'm not entirely sure of its direct relevance myself). Martin  (Smith609 – Talk)  20:35, 5 May 2009 (UTC)
 * Logically you're right, the fact that in the 1970s the BS was the only known big early Cm lagerstätte means its fossils can be interpreted either way, "it all happened even faster and more flamboyantly than we thought" or "this shows how much remains cryptic". It looks to me as if the BS fossils were conscripted (esp by Gould) on the side of punk eek against gradualism, and Gould reinforced this by following Seilacher's "Vendiobionta" interpretation of the Ediacarans. I'll recheck the existing refs on that point. --Philcha (talk) 09:37, 7 May 2009 (UTC)


 * More recently, we have discovered:
 * Diverse Ediacaran biota (including modern phyla?)
 * Gradual increase in Cambrian complexity
 * That does not appear to be a universal view, see the sources I cited (SCM 2000; Marshall). The similarities between Chengjiang and BS make it appear that the main animal groups appeared before Chengjiang, although I could find no sources for that. --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * I was thinking of Caron 2006, but probably over-extending its scope. Either way, I guess we remain uncertain about how long the 'explosion' took (however we choose to define it). Martin  (Smith609 – Talk)  20:35, 5 May 2009 (UTC)
 * Too right about the uncertainty. Somewhere (poss in Cambrian explosion rather than here) I think we should use "The "Cambrian explosion" is a poorly-defined term that refers to a period of time some 600–500 years ago" - The Cambrian Fossil Record and the Origin of the Phyla (Budd, 2003), which ties in with your comment about a discussion in which Budd said is was unrealsitic to tery to define the time-range precisely. --Philcha (talk) 09:37, 7 May 2009 (UTC)
 * Other Cambrian lagerstatte
 * How to classify oddballs
 * Strictly speaking this should follow how the BS fossils appeared to favour the "explosive" interpretation, as Briggs & Whittington published their first cladogram in 1981, before any of the Early Cm soft-bodied discoveries outside the BS. The "counter-revolution" was based on theoretical grounds, and led by the "revolutionaries" themselves. --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * How is the BS significant now?
 * Potential of stem theory - relationships between modern groups, and their ancestral forms
 * "How is the BS significant now?" is a tricky question, because it can be interpreted in a variety of ways. The cladistics revolution changed views of the "weird wonders", but has not resolved current debates about the timing of and reasons for the metazoan radiation. I have a feeling that, while the BS will (per Caron & Jackson) produce new fossils, its theoretical heyday was in the 1970s and 1980s - unless it produces a new fossil that causes another paradigm shift. --Philcha (talk) 19:30, 5 May 2009 (UTC)
 * We should The Cambrian Fossil Record and the Origin of the Phyla (Budd, 2003) for explanation that random extinctions of (sub-)lineages have exaggerated the differences between the extant phyla. --Philcha (talk) 09:37, 7 May 2009 (UTC)


 * I think our difference over the situation before Whittington's 1971 paper on Marella 1971 are just presentational. The idea of Precambrian life only became respectable after Tyler & Barghoorn's 1955 paper on the Gunflint chert became widely accepted, but there was still a 1600 MY gap between Gunflint & the Cambrian.
 * I'm not sure about the present-day significance of the BS, as I said I think its theoretical heyday was in the 1970s and 1980s. What's your view? Perhaps if we agree on where we are to-day and on what the situation was 1950-1971 we can find a route between these points. --Philcha (talk) 19:30, 5 May 2009 (UTC)


 * How would you counter the suggestion that the B.S. has no significance at all in relation to the C.Ex?


 * Areas that it is undoubtedly significant are:
 * Ecosystem reconstruction
 * Reconstruction of stem-group forms / phylogenetic lineages
 * Martin  (Smith609 – Talk)  20:35, 5 May 2009 (UTC)


 * That makes sense, provided you can supply good refs for the BS's continuing significance in these areas. --Philcha (talk) 16:26, 6 May 2009 (UTC)


 * I'm afraid I think your recent changes have been in the wrong direction. I thought the intro part of the preceding version had a fairly clear structure: Darwin's dilemma; evidence of Precambrian life ignored; the Cloud vs Glaessner debate. Your changes also introduced 2 statements not supported by the sources already cited, i.e. they need new sources:
 * "Because the correlation of Cambrian rocks was poorly constrained in Darwin's era, the impression was one of animals appearing instantaneously, from nowhere." I'm not sure this is necessary, as better correlation would not have helped - although the spread of these animals might have appeared nore gradual, the earliest instances of these moderately complex animals would still appear to have materialised from nowhere.
 * "These appear relatively suddenly and are a major contributor to the illusion of a 'complex life from nowhere' scenario." If that can be sourced, then it's valuable. Chronologically, Tyler & Barghoorn's 1955 paper on the Gunflint chert made the idea of Precambrian life respectable, but did nothing to bridge the gap between their cyanobacteia and the trilobites & echinoderms about . The Russians did a lot of research on SSFs in the 1960s, but this was not published in English until 1975 - after Whittington's Marella] (1971) and Yohoia (1974) papers, and same year as his Opabinia (1975) paper.
 * If we get a good source for the SSF's appearing to support the "explosive" view, I suggest we move SSF's to go after the impact of the 1970s papers by Whittington & co. This order better reflects the chronology of thinking in the West and makes the "cladistics counter-revolution"TM more striking.
 * Meanwhile while looking for the date of Whittington's Yohoia paper I've found a new source and will look to see what can be extracted (The origin of animal body plans). --Philcha (talk) 16:26, 6 May 2009 (UTC)


 * But Darwin doesn't have a dilemma if there is evidence of preC life - so I think that this needs introducing before the dilemma? Martin  (Smith609 – Talk)  16:32, 6 May 2009 (UTC)
 * It depends on which aspect of the Gunflint bacteria you emphasise. There was life as far back as ; but it was a far cry from the moderately complex bilaterians that appear in the fossil record around . For the purposes of this article I think the 2nd is the more useful. But I don't know what sort of debates were going on about the Ediacara biota in 1970. For example, if in 1970 the Ediacarans were regarded as closely related to Early Cm bilaterians, Darwin's dilemma is mitigated but Whittington & co. sharpened it again (like the rhyme about Newton & Einstein) --Philcha (talk) 17:00, 6 May 2009 (UTC)

I've re-drafted again, following more stricly what I think the chrono order is, as I think that wil make it easiest to understand how it all developed. --Philcha (talk) 20:29, 13 May 2009 (UTC)

Martin, a week ago you commented: 
 * Areas that it is undoubtedly significant are:
 * Ecosystem reconstruction
 * Reconstruction of stem-group forms / phylogenetic lineages

Would you like to expand on that and / or provide refs? --Philcha (talk) 20:29, 13 May 2009 (UTC)

Once we get this section right to our (temporary) satisfaction, I suggest we get on with Burgess Shale - I suspect that once that's fairly well developed we'll want to re-consider what does on what article, so there no point in going for GA with Fossils of the Burgess Shale very quickly. --Philcha (talk) 20:29, 13 May 2009 (UTC)

- - - - - - - - - - - - - - - - - -

Nuggets from The origin of animal body plans: PS I now think we have enough to cover about the BS and similar fossils, so no space to go into Ediacarans in any detail. In any case I think it's Gould who makes the biggest deal of them and his Wonderful Life, although published 1989, presented a very 1970s view except where Seilacher's Vendobiota (1984) suited him. --20:29, 13 May 2009 (UTC)
 * "most of today's animal phyla originated at least as early as 520 M years ago" (p 65)
 * Glaessner intepreted various Ediacarans as cnidarians, annelids and arthropods in papers 1958, 1959, 1969, 1971, 1978 and 1984 (p 65)
 * Seilacher proposed Vendobionta 1984, 1985, 1989. Pflug had made similar proposals in 1971, but in German. (p 65) --Philcha (talk) 17:10, 6 May 2009 (UTC)

Early Cambrian stratigraphy
Hello Martin and Philcha! I prepare materials about Upper Vendian-Lower Cambrian stratigraphy and SSF for Wikipedia on base of correct and new information from Russia and China. The preliminary result: http://vendian.net76.net/tommotian.htm I think, it will be useful for this discussion. Aleksey (Alnagov (talk) 20:58, 6 May 2009 (UTC))


 * Hi, Aleksey! I waited for Martin to comment, as he knows more about stratigraphy than I do - on a good day I can spell the word, on a great day I can type it correctly. Martin seems still to be thinking this over, so I'll be very rash and make some comments.
 * I already knew that Cambrian stratigraphy was a mess, and while looking for some background on the page you mentioned I found palaeos.com's page with its links and the amusing diagram that shows how the dating of the Cambrian has changed sinced 1980, and the same site's satirical comments on this messy issue - plus Geologic time scale 1989 (Harland; pp 31-34), which will be a good ref for the difficulty of the issue and the history of attempts to resolve it - having a date stamp in the book's title says enough. I'm also aware that Russian scientists think the "official" timescale is mistaken, and they have to be taken seriously because some many of the rocks and the researchers on the latest Proterozoic and earliest Cambrian are Russian.
 * I think this is too big and complex a subject for an article on the Burgess fossils. I suggest we copy this to Talk:Cambrian and continue there, with the intention to update Cambrian and then, when that's settled, summarise in other relevant WP articles. The stratigraphy issues may turn out to need so much explanation that an article is required just about them, e.g "Proterozoic-Cambrian boundary", so that Cambrian has room for other sub-topics like paleoenvironments and paleogeography.
 * Improving WP's coverage of this is not going to be a quick job, because it's a complex and controversial topic. I suggest that in the meantime articles like this one on the Burgess fossils follow the chronology currently in use - not because it's known to be correct (nothing is, in early Cambrian stratigraphy), but because there's no point in putting a lot of work in to dependent articles before the main one is in good shape. Then when the issues are resolved (as much as they are going to be) we can follow the "what links here" links from Cambrian and update the linked articles, including this one on the Burgess fossils.
 * BTW did you produce the image comparing Russian and western views yourself? A simplified version of that would be worth several thousand words. --Philcha (talk) 09:40, 7 May 2009 (UTC)


 * It will certainly be useful for discussion, although I agree with Philcha that this is not the best place for it. I think the next stage would be to assemble a range of published sources to back up your image; perhaps an article on 'Stratigraphy of the Cambrian' is in order, and would be a good place to develop a discussion of the points of view? Martin  (Smith609 – Talk)  15:01, 7 May 2009 (UTC)


 * I have placed it here to show the time of occurrence of some organisms and an abundance of early Cambrian life, before the time Burgess Shale. I have moved the talk about this scheme here Proterozoic-Cambrian boundary. Where and as this information will be published in Wiki, we will decide it afterwards. Aleksey (Alnagov (talk) 16:15, 7 May 2009 (UTC))


 * I think that formulating an article helps clarify what the issues are so I'm starting on Stratigraphy of the Cambrian. Feel free to edit the page or its talk page as it takes shape. Martin  (Smith609 – Talk)  16:56, 7 May 2009 (UTC)

Comparison w/ earlier/later faunas
I'm a bit stumped as per what could go in here. AFAIK there hasn't been any detailed comparison of the BS to SP or CJ, and I don't think there is anything general which can be informatively stated. Of course, the different taphonomic setting renders comparisons to non-BS-type assemblages meaningless. What were you planning for the section, and is it necessary? Martin  (Smith609 – Talk)  21:19, 8 May 2009 (UTC)


 * The first aspect I thought of was with Chengjiang and Sirius Passet, ecological niches, mix of taxa, etc. My impression (possibly quite wrong) is that BS and Chengjiang are relatively similar despite the gap in time, while Chengjiang and Sirius Passet are more dissimilar despite being fairly close in time.
 * Then there's scope for comparing the BS fauna with the "typical Paleozoic fauna" after the Ordovician radiation, and possibly with lateish Edicaran faunas.
 * I was hoping you'd take the lead in this, even if only to point out why it's a bad idea. Otherwise I'l have to start searching to see if there really anything to write about. --Philcha (talk) 22:21, 8 May 2009 (UTC)


 * The SP has a significantly different taphonomy, which means that different things are likely to be preserved. And remember that the error bars on the dates of the individual beds are pretty much in the 10s of millions of years.  SP has a rather limited number of taxa which, AFAIK, precludes any meaningful statistical analysis. Martin  (Smith609 – Talk)  15:30, 10 May 2009 (UTC)


 * You did take "the lead in this, even if only to point out why it's a bad idea" :-/
 * Anything else we need to cover? --Philcha (talk) 15:40, 10 May 2009 (UTC)


 * Nothing springs to mind. I think we're looking pretty complete. I'll endeavour to read through and copy edit everything in my tea-breaks; then we might be ready to invite people to peer review the article. Martin  (Smith609 – Talk)  15:07, 11 May 2009 (UTC)


 * Yes, I thought we'd covered the ground. I think we still need to sort out "Theoretical importance". After that, and before copy-editing or peer review, we should perhaps draft out a structure for Burgess Shale. My guess is still that there's enough to justify separate articles about the formation and the fauna, but I'm less sure than I was a month ago. --Philcha (talk) 17:02, 11 May 2009 (UTC)


 * There's a lot more about the shale in this article than I had envisioned being here at first, but I think there is still scope for its own article, which will go into much more detail about the geology, extent, discovery and so forth - these topics only need introducing in this article. Martin  (Smith609 – Talk)  17:38, 11 May 2009 (UTC)

To do
Needed to make this comlpete enough for GA:
 * Something on the other Early-Mid Cambrian soft-bodied faunas - not as detailed as I proposed above, more a condensed version of the summaries at this old version of Cambrian explosion. We should also note others of similar age, e.g. in Utah ([[Wheeler Shale) and Australia. I suggest this should come after the "critters" section.--Philcha (talk) 06:29, 23 May 2009 (UTC)
 * Geography. Ideally we should cover both current and paleo- geography. For the paleo-geography, we'd need to check how by much reconstructions differ. The biggest problem is getting hold of maps that are suitable and has no copyright problems. --Philcha (talk) 06:29, 23 May 2009 (UTC)

New Nature article
Collins D. (2009). "Misadventures in the Burgess Shale". Nature 460(7258): 952–53. Haven't seen the paper yet, but noticed it wasn't mentioned in the article. Cheers, Sasata (talk) 03:29, 29 September 2009 (UTC)


 * Thanks, Sasata! That section was written before "Misadventures in the Burgess Shale" was published. I've used it to improve the "history of discovery" section. If you have time, tell me what you think of the new version. --Philcha (talk) 06:51, 29 September 2009 (UTC)
 * I think the article is very interesting, the more so because I live only a province away! If no-one beats me to it, I will pick up the GAR in a week or so (when my plate is not so full) and give you a very detailed opinion. Sasata (talk)
 * Only a province away! Curiously, my collaborator User:Smith609 is doing a PhD under Caron at the Royal Ontario Museum, which has overtaken the Smithsonian as the largest Burgess Shale collection. --Philcha (talk) 08:29, 29 September 2009 (UTC)