Talk:Ediacaran biota
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Timeline
editCan we do something about the timeline? It's kind of ugly-looking, like the fonts are badly pixelated... Adam Cuerden talk 12:08, 8 June 2007 (UTC)
- It's difficult to do anything whilst retaining an easily editable wiki syntax - which I feel is vital given the certainty that details'll change significantly as time goes on. Unless I were to write a new "timeline" template.... *lighting up of eyes in slightly manic fashion* Verisimilus T 07:25, 9 June 2007 (UTC)
- Heh heh. Oh, dear. Adam Cuerden talk 08:02, 9 June 2007 (UTC)
Nama-type assemblage
editDid some more editing. I've changed "sandbars in the mouths of a delta's distributaries" to "sandbars in a river delta". This is certainly simpler, but it's not quite as specific. change it back if you think this removes too much information.
- The two environments are subtly different - one is marine, one is freshwater. Verisimilus T 16:32, 17 June 2007 (UTC)
- Good point. What about "sandbars at the mouth of a river delta"? Adam Cuerden talk 17:26, 17 June 2007 (UTC)
Also, there's a citation needed tag in there. Can you get that? Adam Cuerden talk 03:43, 17 June 2007 (UTC)
- I found a source! Adam Cuerden talk 02:48, 18 June 2007 (UTC)
Also, I've tried to clarify the underside/upperside preservation. in "What is preserved?" I think this is right: "The rate of cementation of the overlying substrate, relative to the rate of decomposition of the organism, determines whether the top or bottom surface of an organism is preserved. Most disc-shaped fossils decomposed before the overlying sediment was cemented, and the ash or sand slumped in to fill the void, leaving a cast of the underside of the organism." Adam Cuerden talk 03:48, 17 June 2007 (UTC)°
- I might have to look into some of Narbonne's stuff to clarify properly. On it. Verisimilus T 16:32, 17 June 2007 (UTC)
- I've checked the original: It looks like that's right. "In the simplest case, a bulb seated with the basal protuberance in clay, suffers burial under a layer of sand at least as thick as the exposed height of the bulb. Collapse or decay of a hypothetical upper surface would allow sand to cast the basal impression in the underlying clay" Adam Cuerden talk 02:48, 18 June 2007 (UTC)
Lastly, should
"Mark McMenamin goes one step further, and claims that Ediacarans could not be animals because they did not possess an embryonic stage." read "Mark McMenamin goes one step further, and claims that Ediacarans could not be animals because, as far as is known, they did not possess an embryonic stage.
- I'm not sure. The claim is based on the assumption that they do not have an embryonic stage; if it's proven that they did, it's invalid. I suppose that the claim is that they don't have an embryonic stage, and the (a?) logical conclusion is that they're not animals. Verisimilus T 16:32, 17 June 2007 (UTC)
- Aye. But at the moment, we state their lack of embryonic stages as a fact, is this definitely true, or is it a presumption of McMenamin that we have to mark as such? Adam Cuerden talk 17:26, 17 June 2007 (UTC)
- I've disambiguated it - it's McMenamin's claim. Verisimilus T 10:20, 20 June 2007 (UTC)
- Aye. But at the moment, we state their lack of embryonic stages as a fact, is this definitely true, or is it a presumption of McMenamin that we have to mark as such? Adam Cuerden talk 17:26, 17 June 2007 (UTC)
Timeline
editName
editInsted of putting Aboriginal language we might have to put Kuyani language, well we wouldnt say water is from a european language would we! Reference is http://listserv.linguistlist.org/cgi-bin/wa?A2=ind0405&L=australian-linguistics-l&D=1&P=264 Enlil Ninlil 05:15, 30 August 2007 (UTC)
Preservation
editWhy to whom in "The Ediacaran biota had soft bodies and no skeletons, making their abundant preservation surprising.[to whom?]"?
The Fossilisation section below describes this in more detail. — Preceding unsigned comment added by 86.180.25.244 (talk) 12:41, 18 September 2014 (UTC)
Diversity across the Ediacaran
editJust to flag up the a recent paper which could benefit the article. Verisimilus T 11:08, 25 March 2008 (UTC)
Multicellular
editRe: "earliest known complex multicellular organisms." - Nobody really knows. I've seen no evidence that confirms nor denies multicellular status. There is/was a biologist who claims that they may be giant single cells, but I don't remember the name. Large plants (several cm) or parts of plants composed of a single cell do exist now. The majority presumption is that they are multicellular, but may be merely current-life bias. --Tablizer (talk) 01:53, 5 May 2008 (UTC)
Update: see about Gromia sphaerica, a single-celled organism leaving eye-visible trails on the sea floor:
http://www.abc.net.au/science/articles/2008/11/24/2427811.htm
Ecological specialisation rather than evolution?
editI find it surprising that the article cites Grazhdankin's paper "Patterns of distribution in the Ediacaran biotas: facies versus biogeography and evolution" (Paleobiology, Spring 2004) several times but does not mention what seems to be the paper's main theme: irrespective of time or location, there is a strong correlation between the paleo-environment and the genera found, and nothing else seems to make a difference. -- Philcha (talk) 20:30, 10 July 2008 (UTC)
Date range
editThe lead says 580-542MYA but the body does not spell out the date range, so there's no ref. This will do: Brasier, M., and Antcliffe, J. (20 August 2004). "Decoding the Ediacaran Enigma". Science. 305 (5687). doi:10.1126/science.1102673. Retrieved 2008-07-18. {{cite journal}}
: Text "pages-1115-1117" ignored (help)CS1 maint: multiple names: authors list (link) -- Philcha (talk) 10:39, 18 July 2008 (UTC)
- See the "biota ranges" timeline in the "Assemblages" section. Martin (Smith609 – Talk) 10:50, 18 July 2008 (UTC)
- That section does not mention dates. I made my browser search for "580" and the lead was the only hit. I'd have inserted the ref myself but could not see an obvious place. I think you should do it, to protect the article's FA status after all the hard work you put into it. -- Philcha (talk) 11:17, 18 July 2008 (UTC)
- There's a diagram showing the chronological ranges of each of the three sub-biotas, on the right. As it's in the old timeline syntax, the "580" is rendered as an image. It's already referenced (Grazhdankin 2004). Martin (Smith609 – Talk) 11:56, 18 July 2008 (UTC)
The Origin section states "It took almost 4 billion years from the formation of the Earth for the Ediacaran fossils to first appear, 655 million years ago." This appears to contradict the lead.Syzygos (talk) 02:52, 19 August 2008 (UTC)
- And the main timeline currently says 610 MYA. I don't think Brasier and Antcliffe (2004) supports more than 580 MYA. BTW the "assemblages" timeline (Avalon ... Nama) looks like 575 MYA. -- Philcha (talk) 06:12, 19 August 2008 (UTC)
Some more sources
editMight be useful --Philcha (talk) 13:39, 3 January 2009 (UTC)
Embryos debunked. Precambrian fossils, once thought to be embryos, reinterpreted as... something else — Preceding unsigned comment added by 72.37.244.100 (talk • contribs)
- As the article says at the end, probably not the last word. -- Donald Albury 12:14, 8 January 2012 (UTC)
Improper sourcing
editI was just reading this article, and this seemed strange to me: "Their strange form and apparent disconnectedness from later organisms have led some to consider them a "failed experiment" in multicellular life, with later multicellular life independently re-evolving from unrelated single-celled organisms."
I checked the source page, and it only said some lineages were failed experiments, and that some Ediacarans looked like they shared some characteristics with later lineages. It didn't say a single thing about later multicellular life "re-evolving" from unrelated single celled-organisms.
I'm new to wikipedia editing and am not specialized in this topic, so I don't really know protocol or how this should be rectified. I sincerely doubt the factuality of the above quote, though. —Preceding unsigned comment added by 208.103.250.200 (talk) 02:09, 18 April 2009 (UTC)
- In the Wikipedia there are many incorrect statements, generalizations, and false citing of primary sources. This phenomenon is characteristic and for scientific articles (!) about Ediacaran/Vendian that complicates search of the modern reliable information.
- Ediacaran/Vendian fauna is really very unusual and many members this fauna have no analogues among modern and extinct organisms (Proarticulata: Dickinsonia, Yorgia, Vendia; frondlike: Charnia, Charniodiscus; Trilobozoa,...). The idea of "failed experiment" has been proposal by Adolph Seilacher (and he author of the extreme point of view - Kingdom Vendobionta (earlier Vendozoa)), who suggested that any similarities between Ediacaran fossils and modern animals were either accidental or convergent, and that the Ediacara biota represents an extinct taxonomic group -- a "failed experiment" in the evolution of life. Seilacher has assumed that many Ediacaran fossils were huge unicellular organisms which he has allocated in the Kingdom Vendobionta (Seilacher author of this name) [Seilacher 1992]. But it Seilacher opinion only!!!, and now he reinterpreted Vendobionta as an extinct order (or subclass) related with Foraminifera of Rhizaria.[Seilacher et al 2003, Seilacher 2006, 2007] Majority of scientists do not agree with Seilacher idea (Kingdom Vendobionta or Rhizaria) and successfully deny this idea by new discoveries and researches.
- Usually the term "Vendobionta" is used as = Ediacara biota, Ediacaran fossils/animals/organisms – all organisms what preserved as casts and imprints. I consider that it is incorrectly!
Reffrences:
- Seilacher 1992. Vendobionta and Psammocorallia: lost constructions of Precambrian evolution. Journal of the Geological
Society, London, 149, 607-613.
- Seilacher et al 2003 http://www.jstage.jst.go.jp/article/prpsj/7/1/43/_pdf
- Seilacher 2006 http://www.physics.mcmaster.ca/~odonnedv/OIbook/10_seilacher.pdf
- Seilacher 2007 http://books.google.ru/books?id=GA7-8JIh9IwC&pg=PA387
Aleksey (Alnagov (talk) 10:34, 18 April 2009 (UTC))
Ediacara-type assemblage
editI'm the main author of the Dutch-language article about the Ediacara biota, and while reading this article I noticed something that appeared strange to me. You call the middle assemblage of the biota the Ediacara type, and then you give as reference Erwin 2008 (ref. 87). But he doesn't call it the assemblage Ediacara-type, he and several author authors name that assemblage the White Sea-assemblage.[1][2] And in the figure accompanying the text, the Ediacara SSF and the Miache-type biota are mentioned as well, which are not referred to in the text. Something I find not very clear. Wenkbrauwalbatros (talk) 15:49, 22 April 2009 (UTC)
- ^ Narbonne, G.M.; 2005: The Ediacara Biota: Neoproterozoic Origin of Animals and Their Ecosystems. Annual Review of Earth & Planetary Sciences ,33: p. 421–42
- ^ Xiao, S. & Laflamme, M.; 2009: On the eve of animal radiation: phylogeny, ecology and evolution of the Ediacara biota. Trends in Ecology and Evolution, 24: p. 31-40
Ediacara-assemblage versus White Sea-assemblage
The Russian and other scientists usually use term "Ediacara-type biota" (Ediacara-assemblage) – is a community on well-developed microbial mat in shallow, sunlit environments between wave zone and storm wave zone. It is more correct from the historical point of view, because the first rich assemblage of this type has been found in Ediacara Hills, Australia. For example see: Grazhdankin, Dima (2004). "Patterns of distribution in the Ediacaran biotas: facies versus biogeography and evolution". Palæobiology 30 (2): 203–221.
"Ediacaran biota", "Ediacara biota" and "Ediacara-type biota" have different meanings.
Ediacaran biota (Vendian biota) it is all organisms of the Ediacaran (Vendian) period: bacteria, protista, algae, animals, fungi and others. And Ediacaran biota includes the Ediacara biota and Ediacara-type biota.
Ediacara biota it is = "vendobionta" (the not in Adolph Seilacher meaning as Kingdom or Order/Suborder of Rhizaria) – all organisms what preserved as casts and moulds: Dickinsonia, Kimberella, Rangea, Tribrachidium, Spriggina, Pambikalbae, Charnia, Nemiana, Palaeophragmodictia, Ediacaria, Pteridinium, Onega, Yorgia, Palaeopascichnus, Fractofusus, Vendoconularia,… In typical volume the Ediacara biota consist of Ediacara-type biota (assemblage), Avalon-type biota and Nama-type biota, but not of Ediacaran (not Ediacar"a") shally fossils (Cloudina, Namacalathus), Miaohe biota and Pertatataka assemblage of giant acantomorph acritarchs (Doushantuo fossil embryos).
Else one meanings of Ediacara biota - modern and extinct biota(s) of the Ediacara Hills, Australia.
Such a not pretty mess :-)) Aleksey (Alnagov (talk) 20:02, 22 April 2009 (UTC))
The environment where Ediacaran organisms lived and continents where their fossils are found.
editThey would be around for +100 million years and would represent Earth's first large organisms, found in all continants ESCEPT for South America and Antarctica. Ancestors for trilobites, worms, jelly-fish and sea urchins. —Preceding unsigned comment added by 96.25.220.22 (talk) 03:09, 4 November 2009 (UTC)
I don't see it mentioned in the article, but aren't Ediacaran fauna diploblasts, which develop from two-layered gastrula, as opposed to triploblasts, which develop from three-layered gastrula? --Michael C. Price talk 21:08, 14 November 2010 (UTC)
- Kimberella is regarded as a bilaterian, and possibly as a mollusc - so it appears to have been a triploblast. Arkarua may be a echinoderm. One or both of Spriggina and Parvancorina may be arthropods. --Philcha (talk) 13:39, 15 November 2010 (UTC)
- The interpretation of the (controversial) Vernanimalcula is triblastic; anyway I doubt there's any reliable information on the status of Ediacaran fauna embryology. --Cyclopiatalk 15:27, 15 November 2010 (UTC)
- Okay. Somewhere I had got the impression that the Ediacaran was dominated by diploblasts, but I'm no expert. --Michael C. Price talk 16:06, 15 November 2010 (UTC)
- From DNA to Diversity by Carroll, Grenier and Weatherbee says "Some of the Ediacaran fossils could represent diploblastic forms related to cnidarians or sponges." Patterns of evolution as illustrated by the fossil record by Hallam says "Conceivably all the Ediacaran forms could be diploblastic, but it is likely that some are triploblastic, possibly coelomates, though their assignment to living phyla is difficult." -Ferahgo the Assassin (talk) 00:42, 16 November 2010 (UTC)
- Thanks for that, Ferahgo. --Michael C. Price talk 02:49, 16 November 2010 (UTC)
- From DNA to Diversity by Carroll, Grenier and Weatherbee says "Some of the Ediacaran fossils could represent diploblastic forms related to cnidarians or sponges." Patterns of evolution as illustrated by the fossil record by Hallam says "Conceivably all the Ediacaran forms could be diploblastic, but it is likely that some are triploblastic, possibly coelomates, though their assignment to living phyla is difficult." -Ferahgo the Assassin (talk) 00:42, 16 November 2010 (UTC)
- Okay. Somewhere I had got the impression that the Ediacaran was dominated by diploblasts, but I'm no expert. --Michael C. Price talk 16:06, 15 November 2010 (UTC)
- The interpretation of the (controversial) Vernanimalcula is triblastic; anyway I doubt there's any reliable information on the status of Ediacaran fauna embryology. --Cyclopiatalk 15:27, 15 November 2010 (UTC)
Ediacara or Ediacaran? Also, opening sentence
editThe article is inconsistent in whether it refers to "Ediacara biota" or "Ediacaran biota". Also, I think rephrasing the first sentence to show that it is simply a descriptive term (and not a binomial, for example) would make it potentially less confusing, e.g:
The biota of the Ediacaran period (/ˌiːdiˈækərən/; formerly "Vendian", ca. 635-542 Ma) consisted of enigmatic tubular and frond-shaped, mostly sessile organisms.
At the very least the pronunciation should not be spliced in between the bold title, and words in bold should not be linked. --Paul_012 (talk) 05:44, 12 June 2012 (UTC)
- I was thinking about the same yesterday, it seems "edicara biota" has many more Google hits than "edicaran biota", if that is anything to go by. And yes, your rephrasing might be good. The title was in italics until I removed it, someone must have thought it was a binomial. FunkMonk (talk) 10:59, 12 June 2012 (UTC)
- The term "Ediacara biota" us for assemblage of fossils of soft-bodied organisms which preserved as casts and imprints. This assemblage include Fractofusus, Bradgatia, Charnia, Charniodiscus, Dickinsonia, Yorgia, Vendia, Spriggina, Onega, Pteridinium, Rangea, Ventogyrus, Shwarpuntia, Kimberella, Parvancorina, Vendoconularia, Solza, Nemiana, Vaveliksia, Fedomia, Somatohelix, Tribrachidium, Anfesta, differnt attachment organs (Aspidella, Hiemalora, Inaria, Palaeophragmodictia...) and others. The term "Ediacara biota" not us for microfossils (acritarchs, cyanobacteria,...), algae fossils, mineralized fossils (Cloudina, Namacalathus,...) and trace fossils. Time range of the Ediacara biota around 575-543 mya, is end of the Ediacaran period. The "Ediacara biota" named after the Ediacara Hills in South Australia, not after the Ediacaran period. And the Ediacaran period named after the Ediacara Hills in South Australia, not after the Ediacara biota. "Ediacaran biota" is all fossil organisms of full Ediacaran period (635-542 mya). Regrettably "Ediacara biota" and "Ediacaran biota" are often confused in literature. In addition, "Ediacara fauna" is fossils of the Ediacara Hills in South Australia. And "Ediacara fauna" often us as sinonim of the "Ediacara biota"... Aleksey (Alnagov (talk) 14:44, 12 June 2012 (UTC))
- If this is the case it should be clearly noted in the article then. Is there an authoritative source which clearly makes the distinction? --Paul_012 (talk) 08:57, 14 June 2012 (UTC)
Version of English
editAs this is written in British English ('mould', 'behaviour' etc, I have replaced all instances (apart from proper nouns) of 'geologic' with 'geological'. We don't say 'geologic' in British English. 86.133.54.214 (talk) 10:53, 13 June 2012 (UTC)
Taxobox
editWhy doesn't this have a taxobox? --Harizotoh9 (talk) 17:05, 13 June 2012 (UTC)
- It doesn't seem that they're particularly related. FunkMonk (talk) 18:54, 13 June 2012 (UTC)
- Their placement is unknown as well. de Bivort 19:45, 13 June 2012 (UTC)
2012 - Ediacara originated on land not underwater.
edit12/12/12 Ediacaran life on land Gregory J. Retallack
Periglacial involutions and modest geochemical differentiation of the palaeosols are evidence of a dry, cold temperate Ediacaran palaeoclimate in South Australia. This new interpretation of some Ediacaran fossils as large sessile organisms of cool, dry soils, is compatible with observations that Ediacaran fossils were similar in appearance and preservation to lichens and other microbial colonies of biological soil crusts, rather than marine animals, or protists.
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11777.html
184.153.187.119 (talk) 17:51, 14 December 2012 (UTC)
- Wow, if this is confirmed, it is indeed shocking. --Cyclopiatalk 18:37, 14 December 2012 (UTC)
- Yes, shocking if true, but the general response seems to be skepticism. [1] de Bivort 20:18, 14 December 2012 (UTC)
- As I imagined. Let's then put our WP:FRINGE/WP:UNDUE hats when adding this to the article (I'd do it, but I can't now). --Cyclopiatalk 20:53, 14 December 2012 (UTC)
- That commentary article says explicitly that the Nature article does not seem to be significantly more than a summary of what Retallack has already published previously. So I think an easy and appropriate way to treat it is just to add it as an additional citation in the lichen section. de Bivort 22:31, 14 December 2012 (UTC)
- Still, a whole Nature paper is kinda important as a source. Any important new argument made there should be included, IMHO. --Cyclopiatalk 11:56, 15 December 2012 (UTC)
- Anyway, so far Source added. --Cyclopiatalk 12:02, 15 December 2012 (UTC)
- Still, a whole Nature paper is kinda important as a source. Any important new argument made there should be included, IMHO. --Cyclopiatalk 11:56, 15 December 2012 (UTC)
- That commentary article says explicitly that the Nature article does not seem to be significantly more than a summary of what Retallack has already published previously. So I think an easy and appropriate way to treat it is just to add it as an additional citation in the lichen section. de Bivort 22:31, 14 December 2012 (UTC)
- As I imagined. Let's then put our WP:FRINGE/WP:UNDUE hats when adding this to the article (I'd do it, but I can't now). --Cyclopiatalk 20:53, 14 December 2012 (UTC)
- Yes, shocking if true, but the general response seems to be skepticism. [1] de Bivort 20:18, 14 December 2012 (UTC)
The Retallack paper cited here is controversial to say the least. Retallack has a history of interpreting just about any palaeoenvironment he looks at as terrestrial, and considers most of these early impressions, not as animals, but usually fungi or lichen. His interpretations are completely dismissed by all experts in this geological period, as neither the fossil preservation, nor the sedimentology support the terrestrial interpretation. I will edit the text to reflect this; leaving Retallack's interpretation as a possible controversy. Rolf Schmidt (talk) 05:57, 29 May 2017 (UTC)
First animal movement/locomotion Comment
editIs Edicararan as the first animal able to move and the sources currently relevant to this article? Sources: http://geology.gsapubs.org/content/38/2/123.abstract http://phenomena.nationalgeographic.com/2016/06/17/our-earliest-example-of-an-animal-moving-on-its-own/ --CuriousMind01 (talk) 12:59, 18 June 2016 (UTC)
Change in environmental conditions
editThe section entitled 'Change in environmental conditions' says "While it is difficult to infer the effect of changing planetary conditions on organisms, communities and ecosystems, great changes were happening... The breakup of the supercontinents,[etc.] could all have played a part." Played a part in what? The general context implies either the rise of the Ediacaran biota, or its demise with the rise of the Cambrian biota. But I'm not sure. (And for the record, I'm always skeptical of arguments for change because of the breakup or fusion of continents--it seems like that is way too gradual a process to have any effect. But that would be original research on my part...) Mcswell (talk) 17:56, 3 September 2016 (UTC)
- The comment appears to refer to the transition to the Cambrian, but sub-sections such as this one which refer to the demise of the Ediacaran are misplaced in the 'Origins' section. The article was promoted to FA back in 2007, and some changes since then have not been helpful. I would not however agree with your sceptism about the importance of movement of continents. They are crucial in the long run, and can have dramatic effects in relatively short periods - for example the connection of north and south America 3 million years ago has produced great faunal changes as animals migrated between the two formerly separate continents. Dudley Miles (talk) 19:45, 4 September 2016 (UTC)
Evaluation for Class
editEach fact is referenced, and they appear to be reliable sources. Most of the sources seem to be from scientific journals. They also appear to be neutral sources. The article is neutral and doesn't push any particular viewpoint, and only presents information relevant to the topic. Chadlarson (talk) 13:56, 29 September 2016 (UTC)
Avalon Explosion?
editThe third sentence in the lead paragraph states"
The Ediacaran biota radiated in an event called the Avalon explosion, 575 million years ago,[1][2] after the Earth had thawed from the Cryogenian period's extensive glaciation.
If you go to the wiki link on the Avalon explosion, it states: "he original analysis has been the subject of dispute in the literature." with 3 references. This implies that there is not consensus for the existence of the Avalon explosion. Should the wording on this page be softened to reflect that?
Something like: "The Ediacaran biota may have radiated in an event 575 million years ago,[1][2] named the Avalon explosion by Virginia Tech paleontologists, after the Earth had thawed from the Cryogenian period's extensive glaciation. Bgovern (talk) 06:14, 6 March 2018 (UTC)
- Softened. Chiswick Chap (talk) 06:55, 6 March 2018 (UTC)
Also a Rusophycus trace fossil on the picture of Dickinsonia feeding on a bacterial mat?
editI greatly appreciated the magnificent photo of the Yorgia's from the White Sea area, thank you Aleksey Nagovitsyn (User:Alnagov) for adding this excellent picture clearly showing the placozoan feeding pattern of these animals. It is a picture that should really close the discussion on the feeding habits of these very basic animals. However, I did see another trace fossil in the lower right corner which looks very much like a Rusophycus trace fossil which is one of the earliest Cambrian anthropod trace fossils. I wonder whether this had been identified by anyone as such? If correct it would also push back the first appearence of this trace fossil by some 10-20 million years! I have also tried to also include this photo into the Dickinsonia article, but failed. Don't know what went wrong, perhaps somebody else is able to do this. — Preceding unsigned comment added by Codiv (talk • contribs) 12:07, 11 April 2020 (UTC)
- There are no Rusophycus traces on this plate. But the Ediacaran (~545 mya) arthropod trace fossils are known from China (see Chen et al., Sci. Adv. 2018) and in my opinion there is nothing unexpected... An outwardly similar way of feeding Placozoa and some members of the Proarticulata (Dickinsonia and Yorgia) is the single and very weak argument in favor of the relationship between them. Aleksey (Alnagov (talk) 12:27, 12 April 2020 (UTC))
Does one of the Yorgia's show predation?
editThanks Aleksey for responding! One more question on this magnificent picture: the Yorgia that left the chain of trace platforms seems to be missing a part on it's top (north if it was a map) side. This looks like a predator has take a bite out of it. I suppose it has been checked in detail, has there been any consensus on what caused that? It is also shown in the marks, so if something like that had happened, it clearly survived the attack.— Preceding unsigned comment added by Codiv (talk • contribs) 12:07, 11 April 2020 (UTC)
- This body part is pulled up and hidden in the sndstone bed. Do not forget that it was a soft-bodied animal, capable of shrinking, bending. In addition, their fossils are imprints of semi-decomposed deformed corpses compressed by the weight of sand. Aleksey (Alnagov (talk) 09:42, 13 May 2020 (UTC))
FA issues
editSo, I've been looking at this article and I am kind of concerned about a few things:
- There is a fair amount of citations in the lead which don't seem necessary to me. And many of these statements should be in the article instead.
- Many many paragraphs are not sourced.
That said, I see that there are many recent sources. Is someone still maintaining the article? Jo-Jo Eumerus (talk) 23:22, 19 January 2022 (UTC)
Retallak’s ideas given undue emphasis.
editdespite the reservations provided in the article, it still gives undue weight to proposal that the Ediacaran biota Are lichen. 73.158.212.95 (talk) 23:42, 17 December 2022 (UTC)
- Well, given that other scientists have rejected the suggestion (more than are currently cited, btw), it does seem WP:UNDUE to give it quite so many column-inches as if we supported it: who knows, maybe an editor did. I'll add a ref or two and cut the material down a bit. Chiswick Chap (talk) 09:47, 18 December 2022 (UTC)
- Because Retallack himself added about that. Ta-tea-two-te-to (talk) 14:29, 19 December 2022 (UTC)
- Ah, then we've done the right thing. Chiswick Chap (talk) 15:30, 19 December 2022 (UTC)
- Because Retallack himself added about that. Ta-tea-two-te-to (talk) 14:29, 19 December 2022 (UTC)
- Well, given that other scientists have rejected the suggestion (more than are currently cited, btw), it does seem WP:UNDUE to give it quite so many column-inches as if we supported it: who knows, maybe an editor did. I'll add a ref or two and cut the material down a bit. Chiswick Chap (talk) 09:47, 18 December 2022 (UTC)
Comment about top image
editI have moved the following comment from the caption of the top image on the article page to here: It is important to note that this representation is inaccurate; the Cyclomedusa-like organism is interpreted in this image as a jellyfish, a belief which is no longer accepted today.
The caption does say that the image represents the biota of the period as it was understood in 1980. A more up-to-date image would be great, but I don't think the quoted comment belongs in the caption of this image. Discussion of how scientists' understanding of the life forms of the biota have changed belongs in the body of the article. Donald Albury 13:51, 19 July 2024 (UTC)
- I disagree. The image situation is unfortunate, but while we look for an updated one, readers should know right under the image that the depiction is inaccurate. cyclopiaspeak! 07:55, 22 July 2024 (UTC)
- Found a variation of the same image without the jellyfish. While not optimal, I guess it settles the issue until we find a better image. cyclopiaspeak! 08:01, 22 July 2024 (UTC)
Near-collapse of the geomagnetic field
editShould we add that the near-collapse of the earth's geomagnetic field may have contributed to the oxygenation of the earth and the appearance of the Ediacaran biota? Source: https://www.nature.com/articles/s43247-024-01360-4 98.123.38.211 (talk) 02:56, 12 August 2024 (UTC)