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Algae First To Recover After Asteroid Strike

kdawson posted more than 4 years ago | from the can't-keep-the-little-green-guys-down dept.

Earth 86

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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86 comments

Cool (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#29642881)

Cool story bro

Root is like crack (-1, Redundant)

Anonymous Coward | more than 4 years ago | (#29643009)

Root is like crack. Don't smoke it. I did once and got hooked. I ran Mac OS Updates as root. ****, I even had sex with my girlfriend as root. Man, that caused some permissions problems. When I started the road to recovery (logging in as Zacks) my girlfriend was all like: "**** no! You can't get any cause you don't own me an I don't go groups. You don't have the power to read, write OR execute so get out of my FACE" So I was all HELL NO bitch. And she wuz like you do not have root (superuser) privlages so get out of my TruBlueEnvironment! So then I went chown and chmodded her ass to me. Dat be-otch be up in my hizzouse. What what. Holla!

Hmm (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#29642889)

How is that possible? I thought that the earth was created only like 10,000 years ago.

(I kid, I kid, please go easy on me)

If there is another strike (4, Funny)

JohnHegarty (453016) | more than 4 years ago | (#29642891)

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

Re:If there is another strike (1)

cjfs (1253208) | more than 4 years ago | (#29642959)

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...

Re:If there is another strike (1)

shentino (1139071) | more than 4 years ago | (#29653811)

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.

Re:If there is another strike (1)

Gori (526248) | more than 4 years ago | (#29642971)

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

Re:If there is another strike (1)

camperdave (969942) | more than 4 years ago | (#29643317)

Yes, when. In the same sense as "When I win the Lottery...".

Re:If there is another strike (1)

M8e (1008767) | more than 4 years ago | (#29643463)

"...,I will only win $10"

Re:If there is another strike (1)

Gori (526248) | more than 4 years ago | (#29644071)

Yeah, you are right. Except that you can not choose not to play in this one...

Re:If there is another strike (4, Informative)

eldavojohn (898314) | more than 4 years ago | (#29643003)

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.

Re:If there is another strike (1)

Hurricane78 (562437) | more than 4 years ago | (#29649249)

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.

Re:If there is another strike (0)

Anonymous Coward | more than 4 years ago | (#29647605)

yeah, but i am pretty sure you won't be around to welcome them if the strike does occur

Re:If there is another strike (1)

rrvau (1370985) | more than 4 years ago | (#29654349)

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.

Re:If there is another strike (1)

riverat1 (1048260) | more than 4 years ago | (#29665155)

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?

Re:If there is another strike (1)

rrvau (1370985) | more than 4 years ago | (#29666125)

I knew it, there is nothing "lcimate change" can'y do.

Re:If there is another strike (1)

riverat1 (1048260) | more than 4 years ago | (#29666383)

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.

Re:If there is another strike (1)

rrvau (1370985) | more than 4 years ago | (#29667487)

What, not CO2 or Methane from all those dinosaurs breathing, belching and farting?

obiously what they mean (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#29642893)

is that this all happened in the last 6,000 years or so.

Good news for Microsoft (3, Funny)

Chrisq (894406) | more than 4 years ago | (#29642899)

Well, if the scum are the quickest to recover ....

Re:Good news for Microsoft (4, Insightful)

Shakrai (717556) | more than 4 years ago | (#29643383)

Well, if the scum are the quickest to recover ....

Shit, I guess that means we can't count on an asteroid to take care of our politicians and lawyers.....

Re:Good news for Microsoft (0)

Anonymous Coward | more than 4 years ago | (#29644193)

Yes, they will be protected in their underground bunker, where all they can do is prepare for their task of repopulating the Earth with their carefully selected group of females.

Re:Good news for Microsoft (1)

Hurricane78 (562437) | more than 4 years ago | (#29649281)

That's no asteroid! It's a space ship! It will just act like a asteroid when it approaches the giant garbage planet in the Andromeda galaxy.

100 years? Now Way. (5, Funny)

140Mandak262Jamuna (970587) | more than 4 years ago | (#29642909)

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.

Re:100 years? Now Way. (1)

LordSnooty (853791) | more than 4 years ago | (#29648105)

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

See (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#29642933)

And everybody says that it will be only cockroaches and republicans that will survive. There are useful items that will remain and recover.

Re:See (0)

Anonymous Coward | more than 4 years ago | (#29644995)

"And everybody says that it will be only cockroaches and republicans that will survive. There are useful items that will remain and recover."

Hey hey hey hey! Cockroaches are a very important part of multiple ecosystems. There's 4,000 species of them, only about 30 or so are actually associated with human habitations and even then only a small minority are actual pest species. Republicans on the other hand are all pests and serve no important role in any ecosystem, and indeed unless culled will turn any ecosystem into a toxic wasteland filled with 99.8% disease-infested slum and 0.2% gated McMansionvilles.

Wow, fascinating. (-1, Offtopic)

Capsy (1644737) | more than 4 years ago | (#29643017)

Honestly, I think we get a little too hyped about this prehistoric stuff. I mean, if this was 65 million years ago, you will never truely know what was going on unless you invent a time machine. Yes, I know, they've scientifically proven that a celestial body did indeed impact the Earth, and yeah, a bunch of stuff died. Now, take these intelligent human beings that study prehistoric times. Given the fact that it actually requires an abundance of gray matter to figure stuff like this out, as well as a lot of time to do the research and field work, these individuals could easily be tasked to do something important. Something like finding a way to replace gasoline effectively, or curing cancer. Just an opinion, but probably off topic. At any rate, algae and bacteria are obviously going to bounce back faster than everything else. They are simple organisms. Algae may not be single celled, but it's a hell of a lot simpler than a fish. Just an observation.

How about if that old algae is the Key... (1)

viraltus (1102365) | more than 4 years ago | (#29643143)

To cure cancer and finding new source of clean energy? uh?

Re:How about if that old algae is the Key... (1)

Capsy (1644737) | more than 4 years ago | (#29643319)

Even if it was, the algae has, by now, evolved slightly. Different genetics = different qualities for medicine. Besides, algae has been a speculated source of clean energy for a while now. The old stuff is irrelevant now, as all we have is the new stuff. Good try though.

Re:How about if that old algae is the Key... (1)

mrrudge (1120279) | more than 4 years ago | (#29645387)

Because moving every thinking being to study only ( what you ) consider the most important problems of the age makes the entire species massively reactionary, and reduces the amount of broad knowledge that everyone ( including the people doing what you consider important research ) has access to. At the moment we have a form of selection which ensures that people who are interested in, and so probably naturally talented in, doing the research that suits them.

Also, we live in a purportedly free society, *tasking* individuals requires a very controlling central body, which has proved many times to be A Very Bad Idea.

Re:How about if that old algae is the Key... (1)

viraltus (1102365) | more than 4 years ago | (#29653657)

The funny thing is that you are being serious...

Re:Wow, fascinating. (1)

Capsy (1644737) | more than 4 years ago | (#29643155)

How is this trolling? I kept it on topic, and I'm not after responses. Stars.

Re:Wow, fascinating. (1, Insightful)

Anonymous Coward | more than 4 years ago | (#29643731)

No, you did not keep it on topic. The thread is talking about the speed of algae recovery after an extinction event, whereas your thread is about enslaving scientists and forcing them to work in politically correct areas of research.

Re:Wow, fascinating. (1)

mrrudge (1120279) | more than 4 years ago | (#29645553)

" There's an asteroid heading towards the planet ! Quick, retrain everyone to be astrophysicists "

Re:Wow, fascinating. (1)

turing_m (1030530) | more than 4 years ago | (#29643325)

Now, take these intelligent human beings that study prehistoric times. Given the fact that it actually requires an abundance of gray matter to figure stuff like this out, as well as a lot of time to do the research and field work, these individuals could easily be tasked to do something important.

You'd liberate far more of these people if you could somehow nuke slashdot. Yeah, yeah, I know you'd have to destroy kuroshin, digg, and every other internet forum - users would just migrate there for their fix. And the software to create internet forums would need to be taken down too - good luck - try and destroy something with an open source license, it would be like trying to eradicate herpes. And then you'd need to eliminate pr0n. And every computer game. And chess. And cards. And paper. Never mind.

Re:Wow, fascinating. (5, Interesting)

Kingleon (1399145) | more than 4 years ago | (#29644011)

Hi, I'm a paleontologist. So, you actually are asking a very important question, but its a question that every scientist must answer practically every day. Why should we get paid to study what we life? Well, simply, we don't. There are plenty of great scientists out there who don't get grants or jobs because what they do isn't relevant to enough people. Maybe its relevant to 20 other people out there, but not enough of the general public. The mark of a bad scientist is a scientist who can't figure out a workable scientific project and sell public institutions (like NSF) on it. Good scientists, overall, only exist as long as they can find useful things to study.

But what makes paleontology relevant to our daily lives? The study of mass extinctions is really important: we can't do the experiment of killing 50% of the earth's biota or clouding the skies for ten years to see how life responds. But, as humans, we are radically altering ecosystems with negative effects which may not play out for thousands of years. We need to understand, having already killed off a massive number of species, how life on earth will respond. Furthermore, understanding the oceans, particularly unpreserved organisms like soft-bodied algae, is important to understanding the processes which control the atmospheric content and the supply of nutrients to larger sea creatures. For example, we know species richness recovery from the KT was delayed in some places for periods much longer than a century. Some thought that was due to a prolonged lack of food. Now we know that the algal production started up so quickly, we know that can't be due to a lack of food; maybe its something else (like a wrecked ecosystem structure).

If you need to know any reasons why understanding the past is important, look up the papers of Jeremy Jackson or David Jablonski. They'll set you straight.

Re:Wow, fascinating. (1)

dpilot (134227) | more than 4 years ago | (#29646119)

Naah, that's all silly liberal crap!

If it makes money, it can't be bad. It's absolutely got to proven bad, in a court of law, with a corpse of the right social class and clear undeniable evidence. And then *maybe* we can do something about it - with voluntary compliance and self-policing, of course.

(I suppose the sarcasm-impaired might need an alert about this post. But if they're THAT thick, no warning I could give would suffice. Isn't it amazing that "conservation" shares its root with "conservative"?)
Thanks for the references of Jeremy Jackson and David Jablonski, though there were several useless hits on both.

Re:Wow, fascinating. (1)

shentino (1139071) | more than 4 years ago | (#29653835)

Pillaging the environment doesn't really "make money"

It's more akin to "borrowing", and then blowing the dough and leaving your kids to pay back the loan...with interest.

Re:Wow, fascinating. (1)

riverat1 (1048260) | more than 4 years ago | (#29665195)

Exactly!

Re:Wow, fascinating. (1, Interesting)

Anonymous Coward | more than 4 years ago | (#29646701)

This is a valid question and should not be marked "troll". It is a question that deserves a serious answer.

Another paleontologist has already answered it well, but I'll give my take as a fellow paleontologist.

The main point I make in the classes I teach is based on an old saying:

"Those who do not know history are doomed to repeat it".

In the case of life, that history is mostly one of extinction -- the destiny for >99.9% of species that have ever lived. Humans are a species of life, so do the math, but wouldn't it be nice to "beat the odds" for a while?

Life on Earth has been through a heck of a lot, so I suppose the extinction statistic isn't surprising. There have been some very bad days on Earth -- days that are on par with Dr. Strangelove "doomsday" scenarios, but naturally caused. From paleontology we know that life will survive in some form even when things are extraordinarily bad, although it takes a while for the global ecosystem to get back on its feet afterward, which is what the cited paper is about.

Would we know about these natural hazards to life on Earth if it were not for paleontology? Probably many of them, yes. There are other ways to get at them. But it is only via paleontology that we can get a sense of the effects on life -- the response to the stress. As I also point out in classes, even if it were practical to whack a 10km asteroid into the Earth to see what would happen, it is an experiment we would not want to run. Fortunately we have a bunch of experiments that were already run, and it is more than just impacts:

What happens when ocean currents change configuration?
What happens when the oceans become more strongly "stratified" into layers ("Strangelove oceans [nature.com] ")?
What happens during volcanic eruptions 100x greater than any in historical times?
What happens when sea level goes up or down?
What happens when half of whole continents are covered with glacial ice sheets?
What happens when whole groups of organisms become extinct?
What happens when atmospheric temperatures or compositions abruptly change (e.g., the Paleocene/Eocene Thermal Maximum [wikipedia.org] )?

All of these are highly relevant questions to the long-term survival of humanity because they could happen naturally or, in some cases, analogous processes could relate to human activity. They are tough questions to answer, but we are fortunate to have access to previous changes that far exceed what we expect in the near future. If we are going to become extinct like most other species have, I'd rather go out knowing that I tried my best to understand and cope with the world that I live on rather than dying out because I was ignorant of my environment and the implications of decisions related to it. This is stuff we need to know. Ignoring it is like living in a house while knowing *nothing* about how to maintain it.

You can always question the priorities of a field of study as obscure as paleontology: is it more important to invest in, say medical science or the development of new energy sources instead of paleontology? You ask this question specifically, and you are right to ask it. Even though paleontology bears on the long-term survival of humanity, which is kind of important (!!), it might be hard to justify with so many urgent problems. I agree that medical science and energy are more important. But my answer is a fairly simple one: have you actually looked at how much money is invested in paleontology versus those other subjects?! ;-) The relative financial priorities aren't out of line, as near as I can tell.

PS: as it turns out, quite a few of the mass extinction events in Earth history are associated with changes in ocean circulation and phytoplankton productivity, which sometimes results in the deposition of organic-rich marine sedimentary rocks. A well-known example is the Cenomanian-Turonian boundary (oceanic anoxic event 2 [wikipedia.org] ). This and other "OAE" events are among the most prolific source rocks [wikipedia.org] for petroleum, and, therefore, understanding them is enormously important to petroleum exploration. Paleontology is also highly effective for determining the age, paleoenvironment, and thermal maturity of rocks in petroleum exploration wells. In other words, understanding OAEs and the application of paleontology to petroleum exploration helps us find more of the oil and gas that will give us the time we need to find those energy alternatives you mention.

Paleontology is an obscure and small field of study, but it is a practical and useful one in its own way.

Re:Wow, fascinating. (1)

ibsteve2u (1184603) | more than 4 years ago | (#29653617)

That was so long that my ass got numb...I think I shat methane hydrate. Whoopsie! See you next mass extinction!

Re:Wow, fascinating. (1)

emilper (826945) | more than 4 years ago | (#29661355)

I think the journalists should take a reality check ...

"were able to document several thousand years of the K-P event in short 150-year-long time-steps" ... so, the minimum resolution was 150 years, but they know the recovery took only 100 years; the K-P event took several thousand years ??

They can tell from a single data point that algae bounced back faster, or that algae did not bounce back faster ? How about the "dip in sterane levels " in the clay deposits "right after the meteorite hit is evidence" that something changed the course of a river or ocean currents ? How did fish survive after a 100 years "dip" in algae levels ?

heh (3, Insightful)

Anonymous Coward | more than 4 years ago | (#29643089)

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

Re:heh (1)

FlyingBishop (1293238) | more than 4 years ago | (#29643191)

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

Re:heh (0)

Anonymous Coward | more than 4 years ago | (#29644209)

Easy. A very deep mine shaft, and a 10:1 female:male ratio [wikipedia.org] .

Seriously, though. We're talking about the extinction of plenty of other creatures, the collapse of the ecosystem, and then its eventual reestablishment by relatively few survivors afterwards.

Re:heh (2, Insightful)

MBGMorden (803437) | more than 4 years ago | (#29644375)

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.

Hollywood has the answers! (1)

abbynormal brain (1637419) | more than 4 years ago | (#29646595)

Didn't you see Jurassic Park?

pics (1)

narfman0 (979017) | more than 4 years ago | (#29643147)

Pics or didn't happen!

Re:pics (1)

camperdave (969942) | more than 4 years ago | (#29643369)

Pics or didn't happen!

Hang on. I'll photoshop some for you.

may i just say (1)

martas (1439879) | more than 4 years ago | (#29643181)

algae rock.

also, #ifndef OVERLORD_STR #define OVERLORD_STR algae
i, for one, welcome our new OVERLORD_STR overlords
#endif

Which is why I ... (1)

clsours (1089711) | more than 4 years ago | (#29643257)

behave so badly. When I die, I will come back as slime, beating you all to the punch by about 500 billion years!

Scientists all disagree! (1)

Dystopian Rebel (714995) | more than 4 years ago | (#29643309)

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 (2, Interesting)

Torodung (31985) | more than 4 years ago | (#29643331)

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:Old science (2, Insightful)

careysub (976506) | more than 4 years ago | (#29646143)

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 stood up to closer investigation.

See for example: http://gsa.confex.com/gsa/2003RM/finalprogram/abstract_47695.htm [confex.com]

Since the distribution of dinosaur fossils close to the KT event has received by far the most scientific attention the failure to find any surviving lineages after the event is striking.

I would be fascinated to know what actual evidence (as opposed to speculation) that your unnamed, unsourced microbiologist could possibly have of a disease striking all non-avian dinosaurids, given the limitations of the fossil record. Proposed alternate scenarios (generally lacking any evidence) are all over the map and are a dime a dozen. Looking at all conceivable possibilities is good science, but one needs to keep such speculation in perspective.

Working out all of the details about events unfolded around the time of the KT impact, and the recovery period after, is a project that will likely never be finished -- there are so many possible mechanisms, scenarios, and sub-scenarios and the evidence is (and always will be) restricted.

But to assert that "the dinosaurs being destroyed by the asteroid strike is almost mythology" is a fantastic distortion of the situation -- it is not noticing the Amazon rain forest because of all the trees.

Re:Old science (0)

Anonymous Coward | more than 4 years ago | (#29650645)

So, it's merely a coincidence that of all the impact craters we know about on the surface of the Earth, the biggest impact in the last, oh, 250 million years or so just happens to be extremely close to the second-biggest mass extinction?

I know that coincidence != causation, but it is an especially big coincidence ;-)

I think it is reasonable to strongly suspect that the K/T impact relates to the K/T mass extinction, even if its relationship is still a matter of legitimate debate and other processes may be at work in addition to the impact. Personally, I think it is clear that the impact happened at about that time, but maybe the system had already been "primed" by longer-term events, such as the Deccan Traps volcanism, and that made the effects of the impact that much worse when it happened.

Re:Old science (1)

RocketRabbit (830691) | more than 4 years ago | (#29650967)

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!

Re:Old science (1)

careysub (976506) | more than 4 years ago | (#29651605)

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 likely) that one or a few other clades of dinosaurs made it through the main KT extinction event as a disastrously depleted community (since the birds made it, and so did several clades of the reptilians, etc.), but which died out some time later. But if so, we have no convincing evidence of it yet. And, if so, the KT event still gets credit for doing the heavy lifting in sending them to extinction.

Re:Old science (1)

RockDoctor (15477) | more than 4 years ago | (#29665029)

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 understood that they aren't included in the hypothesis of KT extinction of dinosaurs.

BADD!
One fight at a time. Please.

Now it is conceivable (perhaps even likely) that one or a few other clades of dinosaurs made it through the main KT extinction event as a disastrously depleted community (since the birds made it, and so did several clades of the reptilians, etc.), but which died out some time later. But if so, we have no convincing evidence of it yet. And, if so, the KT event still gets credit for doing the heavy lifting in sending them to extinction.

We still have no good idea of why the non-avian dinosaurs became extinct. Which is dissatisfying, but it means that there is another BIG and interesting question to answer.
It's almost enough to make "gardening" (digging around in the crustal ephemera) interesting again.

Re:Old science (1)

RockDoctor (15477) | more than 4 years ago | (#29664943)

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! (5, Funny)

overshoot (39700) | more than 4 years ago | (#29643365)

Anyone with a swimming pool could have told them about the ability of algae to come back from extinction.

What idiot moderator (0, Offtopic)

overshoot (39700) | more than 4 years ago | (#29643633)

marked this insightful?

[Grumble] Kids these days [/Grumble]

Re:Well, DUH! (0)

Anonymous Coward | more than 4 years ago | (#29651985)

My Iron has Algae in it

Re:Well, DUH! (1)

ignavus (213578) | more than 4 years ago | (#29653879)

Anyone with a swimming pool could have told them about the ability of algae to come back from extinction.

But first you have to drop a _really_ big rock onto it.

Asteroid? Really? (1)

srees (1290588) | more than 4 years ago | (#29643375)

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.

Re:Asteroid? Really? (1)

cryfreedomlove (929828) | more than 4 years ago | (#29643407)

Srees, how old is the earth? How do you know?

Re:Asteroid? Really? (1)

srees (1290588) | more than 4 years ago | (#29643789)

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 *this* is how something *is*, when it isn't demonstrable fact.

I'll add that personally, I choose to believe in the theory of Creation, the Bible, the Flood, and that the earth is approximately 7-10 thousand years old. But I don't _know_ that, and can't prove it. After extensive reading of both sides of the arguments, it is simply the theory I choose to believe. I like the USA because here I am free to believe that if I want to. I hope this country maintains it's religious freedoms. But if I'm writing a professional publication, I ought to be careful to express it as a theory, as I certainly can't prove it.

So, I'm not complaining that they believe the theory of mass-extinction via asteroid - that's their prerogative. I'm complaining that they are pushing their theory as fact, when it isn't fact, but is still theory.

Re:Asteroid? Really? (1)

OneAhead (1495535) | more than 4 years ago | (#29643965)

Nice one, cryfreedomlove.

Re:Asteroid? Really? (1, Informative)

Anonymous Coward | more than 4 years ago | (#29645375)

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 that's just my personal take on it. Most people draw a line between the easily verifiable stuff ("facts") versus the more challenging stuff ("theories").

That being said, the evidence in support of the theory of a massive asteroid impact about 65 million years ago is pretty hard to dispute scientifically. Most current arguments center on whether the impact that produced the ~300km-diameter impact crater on the Yucatan Peninsula of Mexico was the sole cause, or whether other factors were involved in the mass extinction. The jury is still out on that part. The question of whether an impact occurred at all, and the approximate age of it (~65Ma), is all but settled as far as the great majority of scientists are concerned. Like any good scientific theory, it's testable, and it could be shown to be wrong (e.g., even "Newton's Laws" are wrong in detail compared to the "theory of relativity"), but it is pretty hard to argue with a gigantic hole in the ground that matches in so many ways the expectations of a large impact. It is sandwiched in the time between when dinosaurs and many other creatures were present (the Cretaceous Period) and when they were extinct (the Paleogene/Tertiary). Even if you want to quibble about the age (65 million years ago), you have to explain what is there and why it coincides with the extinction.

The theory that the Earth is about 7 to 10 thousand years old and that the Earth experienced a global flood was scientifically considered in the 1700s -- it's the hypothesis that scientists of this era started with -- and it was thoroughly negated and abandoned by most scientists by about the 1830s. It just didn't work. You can, of course, continue to believe it for as long as you like, and I will respect your right to believe it, but please don't claim that there is any valid scientific reason for believing it, because there isn't. Scientifically it is on par with phlogiston as an explanation for burning.

Even though the theory of an Earth age of 10000 years or less has been dead in the scientific realm for well over 100 years, it still receives some attention in the realm of philosophy or religious belief. In the scientific realm the only circumstances it isn't negated are scenarios like a created Earth with all the evidence installed to look like it is enormously older, which makes a nice philosophical discussion but isn't scientifically testable at all (i.e. the reason that particular version isn't negated is because it can't be).

In summary, I see your point, because the impact-triggered K/T mass extinction interpretation is indeed a theory, but it is a very strongly supported one. It is therefore ridiculous to place the negated "10k Earth/global flood theory" on par given the HUGE disparity in scientific evidence that bears on these theories. The only reason someone could do that is if they think what happened yesterday is unknowable or untestable scientifically unless someone was there to witness it -- that we can't really know anything about the past, so they are both equally unknowable theories. That's a popular one among people who still believe "young Earth" theories, however, that rationale doesn't work for crime investigation, so why should it be any different for scientific work? The evidence bears witness and is scientifically testable just fine.

This isn't a question of imposing belief or telling other people how to think, it is a question of the basis for a belief -- the ingredients that go into what is eventually a personal decision. And people can choose to include or exclude scientific interpretations as a factor as they like.

You choose to believe an interpretation that was thoroughly scientifically negated a long time ago (19th century), and that hasn't gotten any scientifically fresher in the interim. You have every right to do that, but you should not imply that because the options are theories, they are scientifically on par or have the same sort of basis.

Please don't mistake my questioning of the weak scientific basis for your belief for questioning your right to believe whatever you like, or to include or exclude the scientific evidence or current theories about it as you wish. Please don't mistake the confidence I have in the current scientific interpretation for a failure to question it. Of course it could be wrong. I just don't see any sign yet that it is wrong in any major way (the kind of 'wrong' that would turn millions of years into thousands). I personally find it difficult to accept a 19th-century negated scientific theory as a sound basis for belief. That's my personal problem, but some people have a lot of faith that current science doesn't matter to the equation. I'm okay with that too, as long as they don't attempt to misrepresent what the state of the current theory actually is, or how it scientifically compares to alternatives. You are comparing apples and oranges, not the same thing at all.

My magical toilet (1)

DigiShaman (671371) | more than 4 years ago | (#29643379)

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:My magical toilet (1, Insightful)

Anonymous Coward | more than 4 years ago | (#29643801)

They eat your poop.

Re:My magical toilet (2, Informative)

Anonymous Coward | more than 4 years ago | (#29644073)

Pro Tip:

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

Re:My magical toilet (0)

Anonymous Coward | more than 4 years ago | (#29653869)

'course, then you get mold, but I've got some lizards that'll sort that right out.

Scalpel, please (1)

smithtodda (225580) | more than 4 years ago | (#29643535)

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:Scalpel, please (2, Informative)

Convector (897502) | more than 4 years ago | (#29646517)

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 majority of the Al-26 was gone by 5 My after the formation of CAIs' (commonly taken as age 0 for the solar system). We just don't know that date very well. It's about 4.6 Gya, but we can't say that the Al-26 was gone by 4.595 Gya. We may know that this impact crater on Mars is 10 My younger than another, but don't know either date well enough to say impact A happened at 4.11 Gya and impact B happened at 4.10 Gya. Could be 4.15 and 4.14, for example, but we know the spacing.

Re:Scalpel, please (1)

RockDoctor (15477) | more than 4 years ago | (#29664687)

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 looking at) against the position in the sequence. If you've got a 100mm thick decrease in dinostearane, and your palynology indicates a mean deposition rate of 1mm/year, then you've got a century of depletion of dinoflagellates. Bob's your uncle.
You can do this sort of work on core samples, or at the outcrop. It's a lot, lot cheaper to go back to the outcrop.

cyanobacteria (0)

Anonymous Coward | more than 4 years ago | (#29643579)

I wonder if they classify blue-green algae-cyanobacteria- as algae or bacteria for the purposes of this article

I thought it was cockroaches (1)

awpoopy (1054584) | more than 4 years ago | (#29643649)

And all this time I thought it was cockroaches that was the most resilient.

Re:I thought it was cockroaches (0)

Anonymous Coward | more than 4 years ago | (#29644529)

And all this time I thought it was cockroaches that was the most resilient.

Well cockroaches would still be the most resilient animals. However I guess this is good news for the cockroaches as well, since they are oxygen breathers.

Relevant paper in Science (5, Interesting)

Anonymous Coward | more than 4 years ago | (#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.

Doesn't make it look that serious but... (1)

OneAhead (1495535) | more than 4 years ago | (#29643929)

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. There would be few plants left to eat, leave alone to feed livestock. And I'd be surprised if other aspects of the ecosystem recovered as rapidly as the algea's minimal requirements.

My first thought. (1)

DarthVain (724186) | more than 4 years ago | (#29644635)

Well that's great for the Algae.

I call bullshit. (0, Flamebait)

yourassOA (1546173) | more than 4 years ago | (#29647901)

I live in Alberta. Now can someone please explain why all of our dinosaur fossils are on or near the surface. Also this fish clay in supposed to come from 100 meters underwater but it is halfway up a cliff. Global warming must have melted the ice caps and made the ocean rise 100 meters. Right? And people actually get paid to do this kind of research, what a bullshit waste of money.

Give me an f`ing break. (1)

Jane Q. Public (1010737) | more than 4 years ago | (#29654661)

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?

Re:Give me an f`ing break. (1)

Jane Q. Public (1010737) | more than 4 years ago | (#29654767)

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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