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Earth Science

Algae First To Recover After Asteroid Strike 86

Posted by kdawson
from the can't-keep-the-little-green-guys-down dept.
pickens writes "The asteroid that impacted earth 65 million years ago killed off dinosaurs, but microalgae bounced back from the global extinction in about 100 years or less. Julio Sepúlveda, a geochemist at MIT, studied the molecular remains of microorganisms by extracting organic residues from rocks dated to the K-T extinction (in this research referred to as Cretaceous-Paleogene), and his results show that the ocean algae community greatly shrunk in size but only for about a century. 'We found that primary production in this part of the ocean recovered extremely rapidly after the impact,' says Julio Sepúlveda. Algae leave certain signatures of organic compounds and isotopes of carbon and nitrogen; bacteria leave different signatures. In the earliest layers after the asteroid impact, the researchers found much evidence for bacteria but little for algae, suggesting that right after the impact, algae production was greatly reduced. But the chemical signs of algae start to increase immediately above this layer. A full recovery of the ocean ecosystem probably took about a million years, but the quick rebound of photosynthesizing algae seems to confirm models that suggest the impact delivered a swift, abrupt blow to the Earth's environment."
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Algae First To Recover After Asteroid Strike

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  • by JohnHegarty (453016) on Monday October 05, 2009 @08:15AM (#29642891) Homepage

    If there is another strike I for one welcome our new microalgae overlords.

    • by cjfs (1253208)

      If there is another strike I for one welcome our new microalgae overlords.

      Try spending a month learning their language, then see if you'll welcome them. You thought Klingon sounded bad...

      • by shentino (1139071)

        Well they're not much for taste but you can't beat dealing with a species that spends its life soaking up sunlight, belching out oxygen, and building itself up into edible biomass.

    • by Gori (526248)

      Of course, you mean *when* not if...

    • by eldavojohn (898314) * <eldavojohn.gmail@com> on Monday October 05, 2009 @08:35AM (#29643003) Journal
      You may want to welcome them already. Recent research [physorg.com] shows now that phytoplankton were/are consumers of poisonous ammonia in our oceans. And they produced out of it what plants crave. 'Lytes! No wait, I mean Nitrogen. I'm not a biologist but this latest research seems to imply that our designation of bacterial nitrifiers as most important to the nitrogen cycle is wrong and should be given to Archaea [wikipedia.org]. From that research:

      The new experiments show that the organism can survive on a mere whiff of ammonia - 10 nanomolar concentration, equivalent to a teaspoon of ammonia salt in 10 million gallons of water. In the deep ocean there is no light and little carbon, so this trace amount of ammonia is the organism's only source of energy.

      So I wouldn't be surprised that phytoplankton would be the first to recover after an asteroid strike. Not much needed for them to survive. Apparently if all of this is true, a lot of ecology is going to be rewritten. Exciting times if you're in that field I guess.

      • Uum, why would it be their only source of energy? I know that there are even titan and uranium breathers in the deep sea, living from volcanic heat and needing neither water nor sunlight.

    • by rrvau (1370985)

      If there is another strike I for one welcome our new microalgae overlords.

      Are you saying that Climate Change was NOT responsible for the extinction of the dinosaurs? Heresy, burn them at the stake .. if you can capture the CO2.

      • by riverat1 (1048260)

        Of course climate change was (at least partially) responsible for the extinction of the dinosaurs. You don't think an asteroid of that size hitting the Earth won't change the climate?

        • by rrvau (1370985)
          I knew it, there is nothing "lcimate change" can'y do.
          • by riverat1 (1048260)

            Of course it wasn't the same sort of climate change we're experiencing now. It was a very abrupt cooling due to all of the material thrown into the atmosphere by the impact of the asteroid. It probably mostly fell back out in 10 or 20 years but by then all of the large land animals had gone extinct and the biosphere was irretrievably changed.

            • by rrvau (1370985)
              What, not CO2 or Methane from all those dinosaurs breathing, belching and farting?
  • by Chrisq (894406) on Monday October 05, 2009 @08:17AM (#29642899)
    Well, if the scum are the quickest to recover ....
  • by 140Mandak262Jamuna (970587) on Monday October 05, 2009 @08:19AM (#29642909) Journal
    It definitely did not take 100 years. I saw the satellite footage of earth after being struck by the asterioid/comet in the Discovery Channel. It took less than 5 minutes. In fact mammals that survived evolved into full fledged humans by the end of the program, less than 25 minutes later. It would have been sooner, but the evolution took many breaks and went into statis to accommodate the advertisers. It was really kind of Stephen Jay Gould to have provided for punctuated equilibrium, otherwise the Discovery Channel would not have been able to insert these commercials.
    • Yeah, I saw that bit where an ape morphed into a human in an instant and I felt a bit sad that we presumably evolved away the ability to metamorphosise
  • heh (Score:3, Insightful)

    by Anonymous Coward on Monday October 05, 2009 @08:47AM (#29643089)

    How does one 'bounce back' from *extinction*?

    • The global extinction, not their extinction (though they fared poorly.)

    • Re: (Score:3, Insightful)

      by MBGMorden (803437)

      You make a fare point. Many species survived altogether. We didn't evolve from scratch again within 65 million years - some animals survived and in turn evolved into the species that took the place of the dinosaurs. Saying that these "bounced back within 100 years" strikes me as odd, as there were necessarily lots of species of plants and animals still alive and surviving from the day past the strike up through and past the 100 year mark.

  • by narfman0 (979017)
    Pics or didn't happen!
  • algae rock.

    also, #ifndef OVERLORD_STR #define OVERLORD_STR algae
    i, for one, welcome our new OVERLORD_STR overlords
    #endif
  • behave so badly. When I die, I will come back as slime, beating you all to the punch by about 500 billion years!
  • Scientists can't even agree on what to *call* this so-called event:

    K-T extinction
    Cretaceous-Tertiary event
    K-Pg event
    Cretaceous-Paleogene extinction
    Kreidezeit Weltschmertz

    This proves that the Word of His Noodly Beneficence is the Truth.

  • Old science (Score:3, Interesting)

    by Torodung (31985) on Monday October 05, 2009 @09:14AM (#29643331) Journal

    There is lots of skepticism that the asteroid strike "killed off [the] dinosaurs." I saw a study where a microbiologist claims that many factors contributed to the death of the dinosaurs, but mostly it was disease, a competing lifeform that grew rampant well after the strike. I don't remember his name because it was a TV show, but I'm sure you can track it down.

    In the meantime, this is all I have to offer from the Google:

    http://blogs.discovermagazine.com/80beats/2009/04/29/new-study-casts-doubt-on-the-asteroid-strike-theory-of-dino-extinction/ [discovermagazine.com]

    At this point, because of the data we have available in the sediment record, the idea of the dinosaurs being destroyed by the asteroid strike is almost mythology. Keller's work has gone a long way to confirming that we still don't really understand exactly what happened.

    --
    Toro

    • Re: (Score:3, Insightful)

      by careysub (976506)

      It helps to focus on the observable facts (e.g. the distribution of dinosaur fossils in geological strata) in preference to speculations of individual scientists. The fact is: no fossils of non-avian dinosaurs have yet been conclusively dated above the KT impact boundary, but fossils of a number of non-avian dinosaur genera have been found very close to the KT event (making it extremely likely that they existed at the KT impact time). A few claims of post-KT non-avian dinosaurs have been made, but have not

    • Even the fossil record disproves the theory that an asteroid strike killed the dinosaurs. It took a few million years for them to die off after that event.

      Talk about delayed effects!

      • by careysub (976506)

        Please cite one paper that has not been effectively refuted showing non-avian dinosaurs surviving after the KT event.

        As far as I can tell there aren't any. I previously cited on this thread a paper that refuted one prominent claim of a post-KT hadrosaur.

        Of course one can accurately claim that the asteroid/comet did not kill all the dinosaurs since the birds survived, but it is commonly understood that they aren't included in the hypothesis of KT extinction of dinosaurs.

        Now it is conceivable (perhaps even li

        • by RockDoctor (15477)

          Please cite one paper that has not been effectively refuted showing non-avian dinosaurs surviving after the KT event.

          I'd like to see one too. I don't expect to see one, but I'd like to see one.

          As far as I can tell there aren't any. I previously cited on this thread a paper that refuted one prominent claim of a post-KT hadrosaur.

          Reworked, or something more interesting?

          Of course one can accurately claim that the asteroid/comet did not kill all the dinosaurs since the birds survived, but it is commonly underst

      • by RockDoctor (15477)

        Even the fossil record disproves the theory that an asteroid strike killed the dinosaurs. It took a few million years for them to die off after that event.

        You're right, but for the wrong reasons.
        Relatively recent work has shown that there was around about 300,000 years between the Chicxulub impact and the micropalaeontological events that define the end of the Cretaceous and which correlate with the extinction of the non-avian dinosaurs. (Sorry for the wordiness, but precision is important.)

  • Well, DUH! (Score:5, Funny)

    by overshoot (39700) on Monday October 05, 2009 @09:17AM (#29643365)
    Anyone with a swimming pool could have told them about the ability of algae to come back from extinction.
  • I find it interesting that this article is written as if the theory of an asteroid strike causing a mass extinction had been proven as a fact. Theory != fact! C'mon people.
    • Srees, how old is the earth? How do you know?
      • by srees (1290588)
        I don't know...how old the earth is, or how that question relates to my statement. Sounds like bait.

        /me bites

        I don't appreciate someone telling me it's a fact that the earth is 7 thousand years old, or 7 billion years old, as if it's a fact when no one can prove beyond doubt either way. There are theories of evolution, of creation. Once you write one way or the other as fact, you are telling others how to think, and they tend to cease thinking for themselves. It's a kind of lie, to tell someone that *th
        • by OneAhead (1495535)

          Nice one, cryfreedomlove.

        • Re: (Score:1, Informative)

          by Anonymous Coward

          You can believe all you want, but I believe that if I step out in front of a moving bus, it's the physics of the situation that will determine the outcome, not my personal belief about it.

          All ideas in science are effectively theories. Differentiating between "fact" and "theory" is a bit pointless, given that there is an element of interpretation in the most elementary of observations. It's my personal belief that everything about our perceptions of the world is effectively a "theory" in some sense, but th

  • That's nothing.

    My bathroom has a skylight which is nice to have and all. However, once I clean (scrub) the toilet bowl and then disinfect with Clorox bleach, green algae starts to show up again. Tough little buggers! I think they've adapted to the punishment I inflict on them.

    • Re: (Score:1, Insightful)

      by Anonymous Coward
      They eat your poop.
    • Re: (Score:2, Informative)

      by Anonymous Coward

      Pro Tip:

      Close the lid when you aren't using it. Keeps the sun out, and the algae dead.

  • I'm impressed by the surgical precision of the scientists in their research into a 100-year window embedded in time roughly 65 million years ago.

    • Re: (Score:3, Informative)

      by Convector (897502)
      What they're saying is that it takes algae 100 years to recover from this kind of event, no matter how long ago that actually happened. If the impact were to happen right now, it would take 100 years to recover. If it happened 65 Mya, it takes 100 years to recover. We just don't know the start and end times that well, so they can't say the recovery was done by 65.0001 Mya. Another example is the formation of the solar system. The half life of Al-26 is only about 0.7 million years. So we know the major
    • by RockDoctor (15477)

      I'm impressed by the surgical precision of the scientists in their research into a 100-year window embedded in time roughly 65 million years ago.

      Find an area where macrofossils (or microfossils) indicates that deposition was occurring at around (say) 1mm/year (which is very fast, but not unfeasible). Do very fine sampling on the appropriate interval (which you'll already have approximately located from your palaeontology work) and plot the amount of dinosterane (or whichever other biomarker(s) you're lookin

  • And all this time I thought it was cockroaches that was the most resilient.
  • by Anonymous Coward on Monday October 05, 2009 @10:14AM (#29643863)

    I wish journalists would be more diligent about actually citing the relevant paper [sciencemag.org] from which the news releases are derived. If it is on the web, is it *that* hard for people to stick a link in there?

    Anyhow, I haven't read the paper because I can't get the full article yet, but if some of the recovery they are interpreting after the Cretaceous is related to dinoflagellates [wikipedia.org] (which can be detected as dinosteranes [doi.org] in organic geochemistry work), it wouldn't be surprising that they bounced back fairly quickly: A) many of them form highly resistant cysts [wikipedia.org] as part of their life cycle, and those cysts can survive for years before "hatching" and going back to business as usual, B) many dinoflagellates are heterotrophic [wikipedia.org] or mixotrophic [wikipedia.org] -- i.e. they eat things or they eat things at the same time as using photosynthesis. As a result they could probably survive better than many other planktonic "algae" that are exclusively autotrophs [wikipedia.org] (i.e. photosynthetic). This expectation is confirmed to some extent by the observation of relatively few dinoflagellate extinctions across the K/T boundary compared to many other planktonic organisms.

  • Umm, let's see. As everyone owning a swimming pool can attest (as well as oceanographers studying algae bloom), algae can proliferate in a matter of days. The only thing they need is seawater and a bit of light (filtered light through a layer of clouds would do nicely). Basically, what this says is that sunlight was blocked to an extent that it strongly influenced algae growth for about a century. Geologists may call this a swift abrupt blow, but I wonder how humanity would fare in a 100-year impact winter.

  • Well that's great for the Algae.

  • We know, for an absolute certainty, that amphibians, reptiles, and mammals (or mammal-like creatures) survived this catastrophy. So why is it a big deal that algae came back within 100 years? I am completely mystified why anybody would even think this was a question. Mice were already running around. Why is it a surprise (to anybody with a brain) that algae should also?
    • Okay, I will answer an objection that occurred to me since I wrote that. OP stated that the study showed that the algae was suppressed for 1 or 2 hundred years. Fine. But that is not how this was presented: as though it was a surprise that algae even survived that period.

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