Man touches giant mammoth sculpture in Siberia

The mass extinction that killed off the dinosaurs was known to have coincided with Earth getting hit by an asteroid. Next time, we may be the asteroid, according to Elizabeth Kolbert’s new book “The Sixth Extinction: An Unnatural History.” Kolbert writes that humans are not only “witnessing one of the rarest events in life’s history, we are also causing it.”

Elizabeth Kolbert on Earth’s Sixth Mass Extinction 19 February,2014forum

Elizabeth Kolbert, staff writer for The New Yorker and author of books including "The Sixth Extinction" and "Field Notes from a Catastrophe: Man, Nature, and Climate Change"

  • Beth Grant DeRoos

    How many species have gone extinct since Biblical times or in the last 200 years? And have all of them gone extinct because of humans? How many because of natural disasters of some kind?

    • Chemist150

      Excellent question. And unanswerable, I would imagine. An estimate would be nice to put our contribution in context.

  • Livegreen

    What’s scary is we are having major, potentially unstoppable impacts, on ALL our natural environment: land and marine animals, our climate, and plants.

    Is it only when the last tree has fallen, the last blue fin tuna or shark fin is eaten, the temporary blip of secondary predators is depleted, the land has been depleted of it’s nutrients & erosion kicks in, that our government & religious institutions will ask: who is next?

    As Jared Dimond documents in “Collapse” all this has happened in smaller scale in the past to MANY other civilizations. Unless we change how we act, we’ll be the last ones to go but go we shall. & it will not be pretty.

    (Hint hint: when all the other major food resources are mostly gone, when there’s only one left walking around in abundance and people are hungry, what else is there to eat?

    Sound far fetched? Don’t believe that can happen?…Well, Dimond documents how it’s already happened on smaller scales throughout past civilizations, precisely because they also couldn’t believe the evidence that was right in front of them).

  • Hugh

    The documentary film “Sushi: The Global Catch” examines how, after human’s eat the ocean’s apex predators, secondary predators will surge in growth. With nothing left to keep their populations in check, they will wipe out their prey at the bottom of the food chain before they too die out.

    It might take a couple generations, but then there will be little left in the oceans for humans to eat. What’s on land that isn’t already eaten won’t then be far behind… Including us.

    PS. Because it’s two or three generations from now is it impossible for us to realize & care that it will happen to our grandchildren?

  • Chemist150

    This assumes that humans are above nature. I’m one that believes that we are a part of nature and what we do is perfectly natural on the evolutionary scale.

    The Great lakes come to mind as an example. As industry rose, the heavy metal content of waste water rose and drained into the great lakes. The fish populations dropped dramatically and then rebounded. As the rebound occurred, new environmental standards were imposed for waste water and the heavy metals had to be removed. As a result, the heavy metal concentration dropped in the lake(s) and the fish populations again dropped dramatically.

    This certain was a surprise to many. It was determined that they fish adapted to heavy metal content of the water and when the heavy metals were reduced, it selected against the fish population that was tolerant to the high metal levels.

    The point is, as long as the species is not fully eradicated, it’s selecting for physical and behavioral traits. Slow adaptation is better than abrupt changes as exampled in the lakes.

    • Randy Cook

      It should be important to note that the Great Lakes also introduced nonnative species before the environmental regs. were passed to control the overpopulation of other fish species who had become prominent because of the loss of the top predators. It’s a vicious cycle when we endeavor to control the macro environment.

      As someone else mentions, there is a school of thought that most great civilizations in the modern era collapsed because of environmental stresses caused by both the humans and environmental change. Given the level of pollution that modern man has created, it is reasonable to assume that the same will occur again.

      • Chemist150

        That definitely fits into what I was thinking.

        As an example: If we do, in fact, destroy 2/3 marine life which I think is entirely plausible, we could revert to an agrarian society rather than fishing, possibly due to a collapse. The result may be a waste water stream rich in nutrients that feed algae in the ocean causing massive blooms consuming the abundant CO2 in the water bring the CO2 down quite rapidly. Later we could return to a heavy fishing society.

        Our ability to see out that far is low. There are many variables. Thus, one may argue that slow change is best.

  • Barbara Winkler

    Registration is still open (remarkably) for the UCMP Short Course on Species Extinction.

  • Ben Rawner

    Isn’t this the case of the survival of the fittest? We are surviving and other animals are dying. Right now we think we are at the top of the food chain, but what happens when humans finally get hit by a superbug and we become the extinct animal? Nature is older than we can count and it will always find a way.

    • crazyskier33

      A large point that Elizabeth Kolbert’s book tries to make is that our practices aren’t sustainable. It doesn’t matter that we are more intelligent or resourceful, but that we are not considering long term effects or even imagine the connections between events. Humans don’t have to have a direct threat by an insect, disease or mammal; we can very easily die from limited food and water caused by poor planning and estimation.

      • Laurie

        A tremendous amount of water is used to grow the plants that are fed to farm animals. It would be more efficient if those plants were fed to the earth’s 7 billion human beings instead of the 60 billion farm animals who are slaughtered each year for food.

  • Ehkzu

    Every time a major online media site (NY Times, Washington Post, Scientific American, Economist, many more) runs an article about global warming and its consequences, the comment thread is inundated with angry denunciations of global warming as unproven and a hoax perpetrated by a conspiracy of socialists trying to expand government control plus all the worlds’s 12,000-odd climate scientists seeking grant money.

    Those denunciations don’t come from readers of those publications. They come from paid trolls working for what are called Online Relationship Management firms hired by the major petrochemical firms (especially those owned by the Koch brothers), routing the money through foundations that anonymize their patrons. They use persona management software to let one operative pretend to be as many as 70 different posters, each with a unique IP address and a fully fleshed-out online identity. Google Astroturfing and you’ll see how elaborate it has become.

    As a consequence of this and other propaganda efforts, a majority of Americans now believe that global warming isn’t happening or if it is it’s natural–not man-caused–and no big deal. It’s the same kinds of tactics the tobacco industry used to stave off regulation for decades.

    So that’s what we’re up against, and scientists are ill-equipped to deal with such a barrage of propaganda. It even extends to trying to destroy the reputations and careers of those scientists who speak out.

    • Chemist150

      I know that you’re going to discount everything I say here but I need to say it. I don’t work or get paid by any oil company but methane is our future and this is why:

      The process of serpentinization occurs when the most abundant minerals on Earth (silicates) convert water and CO2 into methane and longer chain organics. Now, looking at the list of ingredients that the companies use for fracking. They have developed this process to a point that they consider it IP and refuse to release key details because they don’t want competitors and the public to know. But, key compounds stick out. They’re injecting the ingredients to make more methane from these minerals (water and CO2) among other things like Benzene and other organic solvents.

      For a chemist, the ah ha moment comes when you see that they add benzylammonium salts. The oil companies claim it’s antimicrobial and yes, it does do that (barbricide) but a chemist immediate recognizes benzylammonium salts as a phase transfer reagent. It can move between the organic and aqueous layers and carry polar component between the layers. Benzylammonium salts are also known to concentrate CO2 in solution, otherwise you’re limited on the concentration the partial pressure brings in the aqueous layer and CO2 would be nonexistent in the organic later which would facility compounds such as methane.

      The fracking companies (the good ones) are doing chemistry on a global scale and only a few companies have the resources to test out global chemistry. That is where my retirement money is going to. Now think about carbon tax and credits. If the oil company is increasing yields and drawing out a wells life more than a decade by doing chemistry on a global scale, they’re going to benefits from having tax breaks by injecting CO2 into the ground but they would do it anyway. They would double their profits by getting a tax break from increasing yields and profits while the people and other industries producing CO2 pay the taxes. The oil company gets the tax credit by dumping the tax liability directly on the people.

      You claim it’s the oil companies saying CO2 is OK but they want you to believe they believe that because they want the tax credit from injecting CO2 in the ground to increase their yields.

      As long as the CO2 is reclaimed CO2 instead of being liberated from mineral sources, it can recycle CO2. With that, it does concern me how much acid they may be injecting which could be liberating a fair amount of CO2 from the mineral which could be converted into methane.

      There may be a true conspiracy; but I doubt it is as simple as the one you believe.

    • Robert Thomas

      Ehkzu, I understand your point and your concern. On boards where I read the posts, I’ve seen the sort of thing you report – opponents who rapidly appear and dominate with posts of vituperative comments as you describe.

      However, I think this may overestimate the moment that the entities you list assign to these venues. I think most of us who read these things and post to them do so as an exercise to see what a small number of others think about our opinions – a small number, compared to the listening audience. And the listening audience is pretty small, compared to that of… TMZ? It seems unlikely to me that those you mention would spend money in this way. Maybe it’s worth their while but I doubt it.

      On the other hand, I’m a real person encouraged by no one to post this stuff and I’ve been accused of being a “trolbot”, or whatever you call it.

      I’m NOT a climate change denier at all – I think that as much as I understand the science and associated statistics, that the cause of the alarming accelerated average warming we see is due largely to post-industrial human activity, primarily combustion of fossil fuel. This puts me in the orthodox science camp, I believe, with respect to this issue.

      I also believe that genetically modified food crops are almost universally safe to cultivate and consume and am generally unconcerned about their proliferation. I understand and sympathize with objections some raise about domination of pesticide-cultivar loops and so on by particular corporate entities but with respect to the technology itself, I find the objections to be poorly made. I don’t mean to provoke an argument about this here, but though I think my views on this subject are ALSO well within scientific orthodoxy, when I’ve expressed them, they’ve sometimes provoked accusations that I’m employed by Monsanto and so on. You can’t know that I’m not, obviously, except that one would hope that a paid shill would do a better job.


    I must bring in the Fermi paradox….Where are they…Fermi was speaking about E.T. his conclusion was that advance technical civilizations always eventually destroy themselves

    • Ehkzu

      They are where they are, that that is too far for them to get here or us to get there. Our fastest spacecraft would need 80,000 years to reach the nearest other star system, and there’s no reason to suppose that there’s intelligent life on all that many planets. We require a very stable environment to thrive, plus temperatures that support liquid water. Not that common. For example, life like ours couldn’t exist around any star we can see in the night sky, because those are all big, bright stars (unlike the yellow dwarf that is our Sun) that change temperature too rapidly for the likes of us.

      • EIDALM

        Ehkzu The universe have been around for 13.7 billion years ,our solar system have been around for only 4.5 billion years , there are trillions of planets across the universe ,with many billions in our galaxy alone with new ones discovered nearly every day ,good number of them may be able support life like that on earth , with that many abundant planets we should at least have heard some radio signal from some , but we have not received a single signal within the last 60 years ,even though they should be billions of habitable planets within a distance where radio wave can reach earth…The spaceship voyager was lunched more than thirty years ago and it is currently on the fringe of the solar system ,very far away ,yet it’s 10 watts radio transmitter signal can be received on earth…So what about our powerful TV and RADIO stations which are constantly transmitting at a power of fifty and one hundred thousand watts ,their signals should reach hundreds or even thousands light year across…May be some ET living on one of this planets will be listening to this morning Michael Krasny vioce ,fifty or hundred years from now….The reverse is also true with all of the billions of possible planets within that range we should have at least few may be tens of technical civilization that can have TV or Radio stations ,perhaps we should be watching their version of I LOVE LUCY on earth today or within the last 60 years since project SETI started , but so far we have heard nothing…My conclusion as that of Fermi is that technical civilizations are very short lived because they they eventually destroy themselves or get knocked out by gamma ray burst.

  • Robert Thomas

    I observe that most peoples’ understanding of the natural world is informed far more by science fiction than it is by scientific inquiry.

    How much is the diversity of species imperiled by the popular notion that creatures may be retrieved at some future convenient date by using their “banked” genetic material?

    This would amount to a microbiological _Silent Running_ scenario, where good intentions actually accelerate the danger, due to false security.

  • Jon Gold

    Without intelligence & technology humans are not the apex predator on earth. This is the fundamental issue. As you say we are clever, so what can we do to ‘correct’ the mess!?

    • belle stafford

      Again, just do a little research to find out all the huge impacts of factory farming and the answer is clear. Stop eating meat!! Forget hybrid cars, forget led lightbulbs. Read world peace diet by dr. Will Tuttle

  • Mark Phillips

    Didn’t raptors adapt to things and evolve into birds?

  • Kilian

    Most predictions about climate change are based on CO2 emissions. I was wondering if Elizabeth Kolbert could comment on the reports of the Arctic Methane Emergency Group ( predicting temperature increase of several degrees within the next decade based on arctic methane release.

  • Ehkzu

    Any kind of regulation to try to slow down C02/methane emissions is fiercely opposed by huge petrochemical corporations and billionaire investors who have spent billions to prevent regulation here and abroad. They will win and the human race and the ecosphere will lose, because when it’s scientists vs. the Koch brothers the Koch brothers hold nearly all the cards–and the Republican Party will do their bidding, no questions asked. So as long as the GOP controls the House there will be no regulation.

  • Debbie Neff McKee

    We’re all the happy frog in the cold water on the stove while the water slowly heats up…and it’s to late to jump out…that’s my take on the philosophical question…P.S. I’m reading the book…it’s great!

    • Bill_Woods

      That doesn’t actually happen. When the water gets uncomfortably warm, the frog jumps out. By contrast, if you put the frog in a pot of hot water, it’s muscles’ll cook before it can escape.

  • Sean Dennehy

    What’s it going to take for the political right to acknowledge anthropogenic global warming?

    • Ehkzu

      Giving the Republican Party more money than the petrochemical corporations give them to deny it. Nothing else would work, because patriotism, care for one’s children and theirs, and respect for science have been sacrificed in favor of tribalism and seeking short-term advantage/profits.

    • belle stafford

      We need to stop supporting factory farming, that’s the quickest way for individuals to have an impact. This means stop or at least cut back on meat, dairy and egg consumption. All of the reasons to stop eating meat are excellent, even if you care nothing for the other species on the planet, there’s our health to consider and the sustainability of life as we know it. The fourth reason is that many more people on the earth could be fed. We don’t have to wait for some self serving political group to do anything, we have the power to make a huge change with our daily food choices.

  • Laurie

    The Food & Agriculture Organization of the United Nations has determined that animal agriculture contributes more to global warming than all forms of transportation combined (Livestock’s Long Shadow, 2006.) “Meat” is a problem for humans, animals and the planet on many levels, and should be included in any discussion on climate change.

    • Chemist150

      The amount of cattle in the US is finally becoming comparable to the number of bison roaming the plains before their slaughter.

      • belle stafford

        Chemist 150, what is the point you are making ?

        • Chemist150

          What’s Laurie’s point?

    • belle stafford

      Thank you Laurie! I see we share the exact same view. I just posted my opinion!

      • Laurie

        Dear Belle, I’m glad you were able to get through on the phone and share this important report with the author. Thank you for doing so.

  • Raymond Welch

    No other hypothesis comprehends the declining pH of the oceans, the retreating glaciers, the shrinking Arctic ice cap. the increasing water vapor content of the atmosphere, the precessing growing seasons, the migration of species to higher latitudes and altitudes, the northward movement of sea species (e.g. lobsters), the rise in global average temperatures, and the accelerating extinctions, than the carbon hypothesis.

    If you are a skeptic, and an adult, you must put forward an alternative hypothesis that explains these macro phenomena better. If you can’t, you are not advancing the conversation.

  • belle stafford

    I was fortunate enough to call in toward the end and ask the author about the huge effects of the factory farming industries on our climate. I was very surprised that she wasn’t aware of the UN Report from 2006 that determined that meat agriculture generates more global warming green house gases than all forms of transportation, COMBINED! Cattle rearing is also a major source of land and water degradation, this is from the article, Livestocks Long shadow, by Hennjng Steinfeld, senior official at the UN. For more info, just google United Nations factory farming. You would think a book on this subject, how humans are destroying the planet and causing the extinction of many species, would address what it probably the biggest contributor to the current scary situation we’re in. Director James Cameron said something like we’re sleepwalking to our own demise, paraphrased. We need to stop eating meat, it’s pure and simple, if we want to have any chance of saving the planet,

  • lonelymoa

    “The Sixth Extinction” was published two decades ago, actually, by Richard Leakey. Great book, by the way.

  • Karl W. Braun

    Humankind, through the agency of anthropogenic global warming, known also as climate change, threatens to leave a legacy of many dire predictions, much more than Elizabeth’s book foretells. Here’s a link to a site describing a wide range of the possible consequences resulting from the unbridled emissions of greenhouse gases:

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