Gwynne Dyer: The Sixth Extinction and the walking dead

    1 of 1 2 of 1

      “There are examples of species all over the world that are essentially the walking dead,” said Stanford University professor Paul Ehrlich. “We are sawing off the limb that we are sitting on.”

      He was talking about the Sixth Extinction, the huge loss of species that is underway right now. It has been discussed in public before, of course, but what Ehrlich and other scientists from Stanford and Princeton universities and the University of California Berkeley have done is to document it statistically.

      Animals and plants are always going extinct, usually to be replaced by rival species that exploit the same ecological niche more efficiently. But the normal turnover rate is quite slow, according to the fossil record: about one species of vertebrate per 10,000 species goes extinct each century. Ehrlich and his colleagues deliberately raised the bar, assuming that the normal extinction rate is twice as high as that—and still got an alarming result.

      In a study published this month in Science Advances, they report that vertebrates (animals with internal skeletons made of bone or cartilage—mammals, birds, reptiles and fish) are going extinct at a rate 114 times faster than normal. In a separate study last year, Professor Stuart Pimm of Duke University estimated that the loss rate may be as much as a thousand times higher than normal—and that includes plants as well as animals.

      “We are now entering the sixth great mass extinction event,” said Gerardo Ceballos of the Universidad Autonoma de Mexico, lead author of the research. “If it is allowed to continue, life would take many millions of years to recover and our species itself would likely disappear early on.”

      Indeed, renowned Harvard biologist E.O. Wilson has estimated that at the current rate of loss, half of Earth's higher lifeforms will be extinct by 2100.

      The previous five mass extinctions, all during the past half-billion years, each wiped out at least half of the existing species of life. Four of them were probably caused by drastic warming of the planet due to massive, millennia-long volcanic eruptions.

      The warming eventually made the deep oceans oxygen-free, allowing sulfur bacteria to emerge from the muds. As they took over the oceans, they killed off all the oxygen-based life—and when they finally reached the surface, they emitted vast quantities of hydrogen sulfide gas that destroyed the ozone layer and directly poisoned most land-based life as well.

      The fifth and most recent mass extinction, at the end of the Cretaceous era 65 million years ago, was different. It was caused by a giant asteroid that threw so much dust up when it hit Earth that the sun was effectively hidden for years. First the plants died, and then the animals. But the cause of the sixth extinction is a single species: us.

      It’s fair to say that we are the victims of our own success, but so is the entire biosphere. There were one billion of us in 1800. We are now seven and a half billion, on our way to 10 or 11 billion. We have appropriated the most biologically productive 40 percent of the planet’s land surface for our cities, farms and pastures, and there’s not much room left for the other species.

      They have been crowded out, hunted out, or poisoned by our chemical wastes. Their habitats have been destroyed. Even the oceans are being devastated as one commercial fish species after another is fished out. And still our population continues to grow, and our appetite for meat causes more land to be cleared to grow grain not for people, but for livestock.

      All this even before global warming really gets underway and starts to take huge bites out of the ecosphere. We are on the Highway to Hell, and it’s hard to see how we get off it.

      In a way, climate change is the easiest part of the problem to fix, because all we have to do is stop burning fossil fuels and reform the way we farm to cut carbon dioxide emissions. More easily said than done, as the history of the past 30 years amply demonstrates, but certainly not impossible if we take the task seriously.

      Maintaining the diversity of species (some of which we haven’t even identified yet) that provide essential “ecosystem services” is going to be far harder, because the web of interdependence among apparently unrelated species is very complex. At the very least, however, it is clear that we must restore around a quarter of our agricultural land to its original “wild” state and cut back drastically on fishing.

      It’s far from clear that we can do that in time and still go on feeding all of the human population, but the alternative is worse. James Lovelock put it very bluntly in his book The Revenge of Gaia.

      “If we continue business as usual, our species may never again enjoy the lush and verdant world we had only a hundred years ago,” he wrote. “What is most in danger is civilization; humans are tough enough for breeding pairs to survive....but if these huge changes do occur it seems likely that few of the teeming billions now alive will survive.”

      Comments

      21 Comments

      kkw

      Jun 21, 2015 at 11:12am

      There is only one way to get off the highway to hell - cut the human population by 99% to return the ecosystem back to equilibrium.

      ken

      A big picky ...

      Jun 21, 2015 at 2:14pm

      The *rate* of extinctions has been cherry picked to make it seem especially scary. The problem is worth worrying about but the "rate" is just "truthy" spin. A ratio of BS/BS.

      You have also missed the big extinctions -- the "snowball Earth" extinction's when the planet was frozen over from pole to pole. The "rate" of extinctions in the Asteroid hit 64 million years ago must have been astronomical. The Permian extinction was slower but wiped out half the species on Earth.

      The quoted statistics compare the theoretical "background" rate of extinction with the hypothetical current "rate". In fact, extinction comes in "punctuated equilibrium" with "spikes" in the "rate" and long periods of *increase* in species. Is there some reason to suppose that, over the next 1,000 years, we will not dramatically *increase* the number of species on the planet?

      The "rate" talk is BS. The problem is that the situation is dangerously out of control. Climate change will drive the "rate" off the scale.

      Wayne Brown

      Jun 21, 2015 at 2:19pm

      The ecosystem has never been in *equilibrium* kkw. Stability is an illusion. This is a treasured illusion of climate change deniers, who imagine that the world (like the economy) will somehow take care of itself. We are in the position to bring back global winter (by nuclear war) or a catastrophic green house effect (by business as usual) *because* the climate is *not* inherently stable. Our efforts to "stop" climate change a "hail Mary".

      Pierre C yr

      Jun 21, 2015 at 10:27pm

      Its proven that its not the behavior of the population as a whole thats the issue but merely the top consumers on the planet. Probably the top 5th at most yet many try to harp on the overall pop instead of the behavior of a relative few. We can feed many times the current pop with a lower environmental footprint than we have now. In a few decades we wont farm as much as grow food in multi storied food factories. If we starve the pop to free up that agricultural land before we can make that transition then we lose civilization. We lose that we lose both surviving and the environment likely to a much greater degree. The solution is modernity and reaching for new tech an efficiencies. easily doable if we moderate the economy and give people the financial and other resources to make changes in their lives. The worst thing we can do is use a bad, inhumane solution, there are many both good and bad, that would almost certainly make the problem worse.

      Du Lang

      Jun 22, 2015 at 2:02am

      I don't have any dogs in this race; I'm childless, so there's no real, moral imperative for me to change much about my life - though I have, to my great 'social status' regret. But like every "engaged liberal", I've got some ideas on "what needs to be done".
      Rethink poverty. Rethink what it means to be "poor". And I don't mean reciting that colossal turdism of "money isn't everything", because our species has effectively made it the primary purpose of human life. Money is a real thing, a convenient unit of exchange that's typically utilized for the purposes of food and shelter, but that also contributes to investment, which in turn is used to 'grow' even more money. Perhaps most importantly, money makes a real change in the agency that people have in their lives. It allows us the luxury of time to make decisions.
      We know that above a certain standard of living, happiness doesn't increase much. We know that as living standards increase, energy use increases.
      So the only real answer is to stop. Stop working to grow the economy. Stop 'working', period.
      Don't start yet another NGO with no 'exit strategy', whose purpose will gradually evolve to earning more money to spread it's message; NGO's are effectively 'anti-corporate' corporations with an appealing social message/branding. Most couldn't exist without capitalist (growth oriented) enemies, yet use those same methods to expand their cause. They sell ideas that are contingent upon the alternative; they're the dialectic.
      If there's a solution, it might look a lot like a minimum income. It might look a lot like people sitting around doing very little and perhaps even accepting that a 'pause' in whatever they conceive of as progress is not bad per se, but in fact, a very necessary thing. Let us go fallow for a bit.
      The problem is that our understanding of what people are for (to reuse Wendell Berry) is tied so gruesomely to 'production', that extricating ourselves from this thinking will be near-impossible. No human being I know personally is ready or willing to accept the haunting decline in social status that comes from "doing nothing", that arises from a self-imposed decision to conscientiously object to how we live. But until minds are changed about what is truly 'the good life' and accept that the things we 'own' do not define us, the problem remains; largely left for those who will live after us.

      Cassius

      Jun 22, 2015 at 5:08am

      Says Dyer: "At the very least, however, it is clear that we must restore around a quarter of our agricultural land to its original “wild” state and cut back drastically on fishing." Good luck! They can't even cut fruit, veg and almond production in California in the face of the worst draught in memory. So how will we be able to restore a quarter of the Western hemisphere's land - let alone the world's - arable land to its original state?

      Well...

      Jun 22, 2015 at 8:37am

      People already enjoy less freedom than they did 10,000 years ago, so, effectively we've already rendered ourselves extinct mentally, now the rest of the environment is simply catching up.

      I personally blame alcohol and the low-grade FAS that passes for "civilization."

      Mosby

      Jun 22, 2015 at 9:03am

      Given ample food (agar), bacteria in a Petri dish reproduce until they occupy all the available space. Eventually, some combination of too little food and too much waste product causes the population to crash.

      Individually, humans are smart enough to avoid that fate, but collectively, human societies throughout history have repeatedly demonstrated their inability to save themselves. Our species will end up killing itself also, because we're collectively too stupid to prevent it.

      @Mosby

      Jun 22, 2015 at 9:16am

      That's why so many intelligent people are anti-socialist. Like anything, society is OK on a certain scale, if it is voluntary, etc. but when it becomes compulsory, that is a sign of a severe crisis. It would be much more honest for the large numbers of violent socialists to admit that their way of life destroys planets and that they're just too inbred and stupid to stop, rather than trying to pretend everyone who isn't a herd-moron has something wrong with him.

      Surprise Surprise

      Jun 22, 2015 at 10:31am

      A friend once said in a discussion on western consumption vs. third world consumption and global resources that he would be willing to give up half our lifestyle if they gave up half their population. This was thirty years ago.

      I think he got the ratio right. And it does address both sides of the issue. I suspect that for everyone to have a western lifestyle we would need to lose three quarters of the total population.

      Take a look at this BBC magazine article: http://www.bbc.com/news/magazine-33133712

      I hope we figure it out.