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Earth Science

Did Land-Dwellers Emerge 65 Million Years Earlier Than Was Thought? 41

Posted by timothy from the why-there's-a-snooze-button dept.
ananyo writes "A controversial paper published in Nature argues that enigmatic fossils regarded as ancient sea creatures were actually land-dwelling lichen. If true, that would suggest life on land began 65 million years earlier than researchers now estimate. The nature of fossils from the Ediacaran period, some 635 million–542 million years ago, has been fiercely debated by palaeontologists. But where others envisage Ediacaran sea beds crawling with archaic animals, Gregory Retallack, a geologist at the University of Oregon in Eugene, sees these sites in southern Australia as dry, terrestrial landscapes dotted with lichens. He proposes that rock in the Ediacara Member in South Australia — where palaeontologist Reginald Sprigg first discovered Ediacaran fossils in 1947 — represents ancient soils, and presents new geological data. Among other lines of evidence, Retallack argues that the rock's red colour and weathering pattern indicate that the deposits were formed in terrestrial — not marine — environments (abstract). Others strongly disagree."
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Did Land-Dwellers Emerge 65 Million Years Earlier Than Was Thought? More

Did Land-Dwellers Emerge 65 Million Years Earlier Than Was Thought?

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  • Life on Land May Not Have Evolved From the Sea (Score:5, Interesting)

    by Hugh Pickens writes ( 1984118 ) on Thursday December 13, 2012 @06:42PM (#42281177) Homepage
    Conventional wisdom has it that complex life evolved in the sea and then crawled up onto land but NPR reports that a provocative new study published in Nature suggests that the earliest large life forms may have appeared on land long before the oceans filled with creatures [npr.org] that swam and crawled and burrowed in the mud. Paleontologists have found fossil evidence for a scattering of animals called Ediacarans that predate the Cambrian explosion about 530 million years ago when complex life suddenly burst forth and filled the seas with a panoply of life forms. Many scientists have assumed Ediacarans were predecessors of jellyfish, worms and other invertebrates [nature.com] but palaeontologist Greg Retallack has been building the case that Ediacarans weren't in fact animals, but actually more like fungi or lichens [wikipedia.org] and that Ediacarans weren't even living in the sea, as everyone has assumed. "What I'm saying for the Ediacaran is that the big [life] forms were on land and life was actually quite a bit simpler in the ocean," says Retallack adding that his new theory lends credence to the idea that life actually evolved on land and then moved into the sea. Paul Knauth at Arizona State University has been pondering this same possibility. "I don't have any problem with early evolution being primarily on land," says Knauth. "I think you can make a pretty good argument for that, and that it came into the sea later. It's kind of a radical idea, but the fact is we don't know." Knauth says it could help explain why the Cambrian explosion appears to be so rapid [wikipedia.org]. It's possible these many life forms gradually evolved on the land and then made a quick dash to the sea. "That means that the Earth was not a barren land surface until about 500 million years ago, as a lot of people have speculated."

  • Okay Slashdot! (Score:5, Insightful)

    by DarkOx ( 621550 ) on Thursday December 13, 2012 @06:50PM (#42281291) Journal

    Look I understand this is a news aggregator not an originator, but its still a website it should be a little ahead of the MSM. Whats the deal with the apparent pattern of posting whatever they talked about on NPR's all things considered the previous day?

    • Re: (Score:2)

      by icebike ( 68054 )

      Mod parent up.

      It seems this ananyo submitter, which resolves to Nature.com (?!!?) submits a story that is "New to Timothy"(tm) who dutifully parrots it back to Slashdot. Neither of them read any other news sources, and apparently listen to NTR on the drive into work, so to them, everything looks fresh and interesting.

      • Re: (Score:3)

        by Omestes ( 471991 )

        "NTR"?

        New Tropical Resort?
        Never Trust Rehnquist?
        Naked Teddy Roosevelt?
        Nevada Television Remotes?
        Narwhal Tap Revival?
        Numismatist Telecommunication Radio?
        Null Thermal Reflux?
        Nigerian Theocratic Rector?
        Nuclear Televangelist Reactor?

      • Re:Okay Slashdot! (Score:4, Informative)

        by ananyo ( 2519492 ) on Friday December 14, 2012 @07:59AM (#42285681)

        hi - there's no conspiracy here. I have no special insight in what slashdot editors look for in a submission but I imagine that if they see a well written synopsis that helps. There's no way slashdot (nor any other aggregator site) could ever be ahead of the MSM (if you include Nature in that) on this - as research papers are sent to journalists IN ADVANCE of publication. This is supposedly to allow reporters time to put together an accurate story but also allows journals to control the news agenda a little. So this is why newspapers around the world publish the same science stories from the big journals at the same time.
        I live in the UK - so I tend to post stuff to slashdot during my morning. If an embargo lifts at 7 or 10pm in the UK (typical journal embargo times), I'm not around to post it until the next day. Other people often do post the same story before I can as a result.
        Lastly, it's no secret that I work for Nature - that's why a link to the news site and some smart googling of my user name reveals who I am. I've noticed the journal Science does the same (sciencehabit). There are good and bad things about that - news stories in Science and Nature are authoritative, in-depth and well balanced. They're far better sources of science news than newspaper coverage by and large, which is patchy and superficial by and large and often fails to address the big holes in the research. Because slashdot has editorial control, the editors get to decide which stories they take and which ones they decline.
        I would add that means that slashdot hasn't suffered from the same problems as some other sites, which link to pretty awful stories or worse, journalism-free press releases that are essentially advertisements from researchers/universities.

      • Re: (Score:2)

        by mcgrew ( 92797 ) *

        You guys forget two facts: Stories are submitted by readers, and voted on in the firehose. Submitted any stories lately? Been to the firehose lately? If not, stop bitching.

  • ... so the answer must be "no". Thanks for clearing that up.

    • Re: (Score:2)

      by mcgrew ( 92797 ) *

      Betteridge's law of headlines is like Hanlon's razor: very often wrong. In fact, Betteridge has admitted to breaking his own law, in an article published at his own site!

  • yes I remember that event, it was a Tuesday.

  • a video about mermaids http://www.youtube.com/watch?v=cgzRv4_HJIY [youtube.com]
    actually quite interesting and somewhat believable....

    The point is.... seek and ye shall find...

    So what do you want to believe..... today?

  • I know Jabberjaw dates back to 1976.I didn't read the article, but are they implying there was marine life even before that?

  • Remember this next time a creationist or global warming denier claims that scientists can't get published if they don't adhere to the party line.

    • Re:Controversial paper published? (Score:4, Insightful)

      by gewalker ( 57809 ) <Gary.Walker@Astr a D i g i tal.com> on Thursday December 13, 2012 @09:21PM (#42283017)

      There is a significant difference between an article that leaves the basis premise alone but changes some of the details compared to an article that attacks the core of the theory.

      Even in the recent case where someone suggested that the speed of light was slightly exceeded by neutrinos the results were broadly assumed to be experimental error because the theory of special relativity is widely considered proven fact. Perhaps a small refinement to SR would accommodate FTL neutrinos -- this would not necessarily destroy the basic theory. Einstein did not destroy Newton, he improved the model.

      If I invented a time machine and go back in time to interview Adam & Eve it would be very difficult for a science journal to accept this evidence as scientific because it violates the very concept of scientific study -- natural causes are always assumed as anything else is not science (this assumption is reasonable). Short of time travel, I would say it is impossible for any theory to replace modern evolutionary theory unless it also has a naturalistic explanation. If I found a complete set of mammal fossils in pre-Cambrian rock it would be publishable in Nature, etc. but this does not mean that most evolutionists would suddenly embrace special creation. Evolutionists would simply modify their their to accommodate new data -- they have modified it a number of times in the past to accommodate new data.

      In the case of global warming the full-blown time-to-panic theory is not well established as a scientific fact, so it is relatively easy to publish against that oppose this -- if you attempt to say that there is no anthropogenic global warning due to industrial greenhouse gases you will find it much more difficult to get it published -- this is how science works.

      • Commenting to remove accidental negative mod points. Nice post!

      • "Einstein did not destroy Newton, he improved the model."

        That depends. When you look at physics narrowly, we could agree that Einstein expanded Newton's physics.

        But there is more at stake. As a natural philosophy, the contents of the two are worlds apart. Newtonian nature was a philosophical center for other thinkers, e.g. Hobbes, and their theories are also questionable.

        In terms of actual content, Newton's world lost, and few (if any) think "Newtonian" anymore. Because it is untrue.

    • The thing is that this paper does not counter the Theory of Evolution, the process is not in question just the order of events and it puts forward a reasoned augment for an alternative sequence of events. As opposed to a creationist article which is science is wrong 'God did it'. Actually all creationist articles are always about no, can't, not, never, sort of like religion really.

  • The assessment by the other paleontologists quoted suggests that the evidence is currently weak.

    And why is red soil color being used as evidence? Don't they analyze the soil to see what specifically makes it red, and use that as the metric? There are multiple causes of soil and rock redness. Perhaps the author merely tried to simplify the writing and excluded causes. But that makes it a bit misleading, implying that visual inspection is sufficient observation.

  • Look closely; those are simply the footprints of Martian elephants. Silly earthlings, dontcha know a piece of Mars broke off and drifted to Earth?

  • By no means a dumb idea, but not especially likely. The Ediacarian/Vendian faunas don't seem closely related to the mainstream faunas of arthropods, echinoderms,brachiopods,vertebrates,etc that appeared a few tens of millions of years later although there are a few tenuous proposed relationships. In all likelihood, the Ediacarians were not ancestoral to the conventional forms. So sure, they could have lived on land (or, one supposes, freshwater lakes) while the conventional forms were evolving in the sea

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