6 ms·

How Long Does Mass Extinction Take?

83 points by zvanness 13y ago

jofer 13y ago
I'm impressed, that's a surprisingly good pop-sci-style article. The writing is clear, correct, accessible, and a nice summary of the scientific context for the paper in question. The original PNAS article is also clearly linked. At least with geoscience, science journalists usually manage to get things horribly wrong. Judging from previous articles, Helen Thompson (the writer) looks like she might be a biologist instead of a geologist, but she nailed the subject matter, regardless.
- mathattack 13y ago
  I agree - well written. Perhaps the only quibble is that my intuition was that it would be much shorter. 60,000 years (or even 5,000) is a long time to react.
  - AutoCorrect 13y ago
    you say react as if there's an awareness by the group of organisms that they are dying out, when that's far from the truth. Think of a species as a network, with the leaf nodes around for only a specific length of time. Add in several events that isolate portions of the network, and it dies off in spurts, as each isolated portion becomes less fit and eventually ceases reproduction. With the decline in our birthrate, it will be interesting to see (from a historical perspective, I'll be long dead) if we die out, or if we get out of this funk we're in now.
    - happyscrappy 13y ago
      Before it was overpopulation, now it is declining birthrate? Why does the narrative always have to be doom? All objective evidence shows substantial progress yet everyone wants to believe in doom.
    - mathattack 13y ago
      I think the decline in birthrate helps us. If we get to under a billion, we strain the planet less. But there are plenty of other ways for us to make ourselves extinct.
rquantz 13y ago
This reminds me of the recent episode of Radiolab that suggested the extinction event at the end of the Cretaceous might have taken only a few hours[1]. If you thought this article was pop-y, you might be in for a surprise, but I found it quite entertaining. [1] http://www.radiolab.org/story/dinopocalypse/ http://www.radiolab.org/story/dinopocalypse/
DanielBMarkham 13y ago
Mankind has most likely already passed an extinction level event with the creation of solid-state circuits. So I guess we'll be finding out shortly (i.e., the next 100-1000 years)
- ASpring 13y ago
  I don't follow. Care to expand?
  - benjamincburns 13y ago
    I think what he's trying to say is "we're all gonna die!!!!"
    - vanderZwan 13y ago
      But how would that follow from solid state circuits?
      - rubinelli 13y ago
        In one word: Skynet
  - iand 13y ago
    Singularity
lettergram 13y ago
I really enjoyed this article, well written and informative. That being said, it seemed to be posted with perfect timing; I was thinking about this walking to work today. What if all of these mass extinctions (hypothetically or other wise) were caused by some species on the planet similar to us. Granted there is NO EVIDENCE for this, but what if... It seems that all mass extinction events happen in similar ways, each time some parts of an ecosystem are disturbed and it collapses. Then, the most highly adaptable (fungi, bacterium, viruses are the most due to their short lifespan) survive. It's interesting to note that it took 30,000 - 50,000 years for the humans to develop this extremely complex society and ecosystem. Perhaps so short that when if we were destroyed this very day nothing would remain, say from nuclear war. All of our buildings would decay and there would be very little remnant in the fossil record. I am not claiming any of this to be true, nor do I even believe any of it to be true. It was just an interesting thought I had that horrified me, and I felt I would share it.
- cbp 13y ago
  A little off-topic but the fantasy series Broken Empire are set in a post-apocalyptic world similar to the one you described. When I read them I thought that was very original.
- nicholas73 13y ago
  I doubt there wouldn't be evidence. A steel building frame probably preserves better than bone. A global population of tool making beings should at least leave some fossil evidence even if their timeline was only 30-50k years. Lastly, the distribution of natural resources might leave some evidence (like not finding ore where you would expect it).
  - DougWebb 13y ago
    Have you seen a steel bridge lately? They require constant maintenance to prevent them from rusting away. Even stainless steel will rust eventually. The only thing that lasts more than centuries is stone, and only the really hard stones will last for thousands of years. The other problem is location. Humans like to build on coastlines, and coastlines shift. We have very little evidence of ice-age era settlements today, but the few sites we do know of show that there were some pretty sophisticated societies around at the time. It's very likely that there are/were more sites, but today they're under a few hundred feet of water off our coasts. As far as natural resources: apparently there are extensive empty holes in the ground around the great lakes that used to be full of copper ore, based on what's left in the walls. So much copper ore that the mining must have gone on for centuries, or involved tens of thousands of people. No one knows who did that, but a likely possibility is the Phoenicians during the Bronze Age. So that's one example of the type of evidence you're talking about, albeit for a more recent period. To go back much further, we'd have to know what kind of resources they were after and where, and hope that the landscape hasn't changed so much that we can't recognize the evidence of resource mining.
Blahah 13y ago
John Baez's excellent Azimuth project has a really good summary of current scientific understanding of mass extinction events: http://www.azimuthproject.org/azimuth/show/Extinction http://www.azimuthproject.org/azimuth/show/Extinction.
ChuckMcM 13y ago
Its a great way of trying to get a more precise timeline. Now I wonder if we should start planting radiometric time capsules, time capsules with long half life materials, a description of what is happening, and a bit of isotope and its stats. Every 10 years you could do another one. And when the next extinction hits, should the life after that be intelligent again, they could find this set of events and date them relative to where they are now. Perhaps we could finish with "Hey we were too silly to leave the planet, don't make that mistake, its totally worth it to figure out how to survive off planet."
- mitchty 13y ago
  This strikes me so much of mass effect 3 and the "sit on your butt and don't decide" ending. Actually its a fun thought problem. How would we convey to a follow up intelligent species what we did wrong if things go bad? Lets assume squid take over the planet (hey why not they're smart), what would we have to do to allow them to understand? We have to control for a lot of situations: * Assume they don't consider past relics a heresy to their religion (assuming again that they even have a corrolary). If they're destroyed in that regard its pretty much wasted effort. * Try and assume how long it would take for intelligent life to re-appear. The timeline for this is somewhat critical to any decision we make on how we build a marker/library of "don't eff this up and get off this rock pronto". Or whatever we choose. I'm sure there are more but I"m at work so not much time to devote to this thought experiment.
  - TeMPOraL 13y ago
    A little off-topic; I got that ending when after few minutes of careful consideration and weighting my moral values I got angry, turned around and shot the hologram. Damn, ME3 has some deep moments. I ultimately went with "take control" ending, saying to myself "please please, don't be evil", as it was the only one that seemed reasonably right. I don't remember any other game where I literally thought for like 10 minutes before making a choice.
- erikpukinskis 13y ago
  I've heard this "survive off planet" concept over and over, and inevitably someone points out that even after the worst conceivable environmental disasters, Earth will still be more habitable than any planet within 1000 years travel. And I've never heard a compelling response to that, so why do people still think leaving the planet is important for our survival? The only scenario I can think of where a radiation-soaked pocket in the Canadian mountains is less habitable than "off planet" is when the Sun starts dying. But that's not really a pressing concern.
lafar6502 13y ago
Previous mass extinction took 60000 years so even if another mass extinction event is happening now we won't even notice it.
- hyperbovine 13y ago
  Because a_k = x implies a_{k+1} = x for all k.
  - lafar6502 13y ago
    how did you know?
duvander 13y ago
Between 12,000 and 108,000 years

83 points by zvanness 13y ago

jofer 13y ago

I'm impressed, that's a surprisingly good pop-sci-style article. The writing is clear, correct, accessible, and a nice summary of the scientific context for the paper in question. The original PNAS article is also clearly linked. At least with geoscience, science journalists usually manage to get things horribly wrong. Judging from previous articles, Helen Thompson (the writer) looks like she might be a biologist instead of a geologist, but she nailed the subject matter, regardless.

mathattack 13y ago
I agree - well written. Perhaps the only quibble is that my intuition was that it would be much shorter. 60,000 years (or even 5,000) is a long time to react.
- AutoCorrect 13y ago
  you say react as if there's an awareness by the group of organisms that they are dying out, when that's far from the truth. Think of a species as a network, with the leaf nodes around for only a specific length of time. Add in several events that isolate portions of the network, and it dies off in spurts, as each isolated portion becomes less fit and eventually ceases reproduction. With the decline in our birthrate, it will be interesting to see (from a historical perspective, I'll be long dead) if we die out, or if we get out of this funk we're in now.
  - happyscrappy 13y ago
    Before it was overpopulation, now it is declining birthrate? Why does the narrative always have to be doom? All objective evidence shows substantial progress yet everyone wants to believe in doom.
  - mathattack 13y ago
    I think the decline in birthrate helps us. If we get to under a billion, we strain the planet less. But there are plenty of other ways for us to make ourselves extinct.

rquantz 13y ago

This reminds me of the recent episode of Radiolab that suggested the extinction event at the end of the Cretaceous might have taken only a few hours[1]. If you thought this article was pop-y, you might be in for a surprise, but I found it quite entertaining. [1] http://www.radiolab.org/story/dinopocalypse/ http://www.radiolab.org/story/dinopocalypse/

DanielBMarkham 13y ago

Mankind has most likely already passed an extinction level event with the creation of solid-state circuits. So I guess we'll be finding out shortly (i.e., the next 100-1000 years)

ASpring 13y ago
I don't follow. Care to expand?
- benjamincburns 13y ago
  I think what he's trying to say is "we're all gonna die!!!!"
  - vanderZwan 13y ago
    But how would that follow from solid state circuits?
    - rubinelli 13y ago
      In one word: Skynet
- iand 13y ago
  Singularity

lettergram 13y ago

I really enjoyed this article, well written and informative. That being said, it seemed to be posted with perfect timing; I was thinking about this walking to work today. What if all of these mass extinctions (hypothetically or other wise) were caused by some species on the planet similar to us. Granted there is NO EVIDENCE for this, but what if... It seems that all mass extinction events happen in similar ways, each time some parts of an ecosystem are disturbed and it collapses. Then, the most highly adaptable (fungi, bacterium, viruses are the most due to their short lifespan) survive. It's interesting to note that it took 30,000 - 50,000 years for the humans to develop this extremely complex society and ecosystem. Perhaps so short that when if we were destroyed this very day nothing would remain, say from nuclear war. All of our buildings would decay and there would be very little remnant in the fossil record. I am not claiming any of this to be true, nor do I even believe any of it to be true. It was just an interesting thought I had that horrified me, and I felt I would share it.

cbp 13y ago
A little off-topic but the fantasy series Broken Empire are set in a post-apocalyptic world similar to the one you described. When I read them I thought that was very original.
nicholas73 13y ago
I doubt there wouldn't be evidence. A steel building frame probably preserves better than bone. A global population of tool making beings should at least leave some fossil evidence even if their timeline was only 30-50k years. Lastly, the distribution of natural resources might leave some evidence (like not finding ore where you would expect it).
- DougWebb 13y ago
  Have you seen a steel bridge lately? They require constant maintenance to prevent them from rusting away. Even stainless steel will rust eventually. The only thing that lasts more than centuries is stone, and only the really hard stones will last for thousands of years. The other problem is location. Humans like to build on coastlines, and coastlines shift. We have very little evidence of ice-age era settlements today, but the few sites we do know of show that there were some pretty sophisticated societies around at the time. It's very likely that there are/were more sites, but today they're under a few hundred feet of water off our coasts. As far as natural resources: apparently there are extensive empty holes in the ground around the great lakes that used to be full of copper ore, based on what's left in the walls. So much copper ore that the mining must have gone on for centuries, or involved tens of thousands of people. No one knows who did that, but a likely possibility is the Phoenicians during the Bronze Age. So that's one example of the type of evidence you're talking about, albeit for a more recent period. To go back much further, we'd have to know what kind of resources they were after and where, and hope that the landscape hasn't changed so much that we can't recognize the evidence of resource mining.

Blahah 13y ago

John Baez's excellent Azimuth project has a really good summary of current scientific understanding of mass extinction events: http://www.azimuthproject.org/azimuth/show/Extinction http://www.azimuthproject.org/azimuth/show/Extinction.

ChuckMcM 13y ago

Its a great way of trying to get a more precise timeline. Now I wonder if we should start planting radiometric time capsules, time capsules with long half life materials, a description of what is happening, and a bit of isotope and its stats. Every 10 years you could do another one. And when the next extinction hits, should the life after that be intelligent again, they could find this set of events and date them relative to where they are now. Perhaps we could finish with "Hey we were too silly to leave the planet, don't make that mistake, its totally worth it to figure out how to survive off planet."

mitchty 13y ago
This strikes me so much of mass effect 3 and the "sit on your butt and don't decide" ending. Actually its a fun thought problem. How would we convey to a follow up intelligent species what we did wrong if things go bad? Lets assume squid take over the planet (hey why not they're smart), what would we have to do to allow them to understand? We have to control for a lot of situations: * Assume they don't consider past relics a heresy to their religion (assuming again that they even have a corrolary). If they're destroyed in that regard its pretty much wasted effort. * Try and assume how long it would take for intelligent life to re-appear. The timeline for this is somewhat critical to any decision we make on how we build a marker/library of "don't eff this up and get off this rock pronto". Or whatever we choose. I'm sure there are more but I"m at work so not much time to devote to this thought experiment.
- TeMPOraL 13y ago
  A little off-topic; I got that ending when after few minutes of careful consideration and weighting my moral values I got angry, turned around and shot the hologram. Damn, ME3 has some deep moments. I ultimately went with "take control" ending, saying to myself "please please, don't be evil", as it was the only one that seemed reasonably right. I don't remember any other game where I literally thought for like 10 minutes before making a choice.
erikpukinskis 13y ago
I've heard this "survive off planet" concept over and over, and inevitably someone points out that even after the worst conceivable environmental disasters, Earth will still be more habitable than any planet within 1000 years travel. And I've never heard a compelling response to that, so why do people still think leaving the planet is important for our survival? The only scenario I can think of where a radiation-soaked pocket in the Canadian mountains is less habitable than "off planet" is when the Sun starts dying. But that's not really a pressing concern.

lafar6502 13y ago

Previous mass extinction took 60000 years so even if another mass extinction event is happening now we won't even notice it.

hyperbovine 13y ago
Because a_k = x implies a_{k+1} = x for all k.
- lafar6502 13y ago
  how did you know?

duvander 13y ago

Between 12,000 and 108,000 years