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>> Kirsten Wiley: So good afternoon and welcome. My name is Kirsten Wiley. I'm here to
introduce and welcome Dr. Peter Ward. He's visiting us as part of the Microsoft Research
Visiting Speakers Series. Dr. Ward is here to discuss the Media hypothesis: "Is life on earth
ultimately self-destructive?" He pointed out that life, rather than to help regulate the earth's
system, does all it can to consume the resources available sewing the seeds of its own extinction.
In contrast to the Gaia, Good Mother theory, he asks, what if it is closer to Medea, a mother who
kills her own children. Dr. Peter Ward's many books include the highly acclaimed "Rare Earth Why Complex Life is Uncommon in the Universe," and "Under a Green Sky." He's a professor of
biology and earth and space sciences at the University of Washington and master biologist with
NASA. So please join me in welcoming Dr. Peter Ward to Microsoft to discuss the Medea
hypothesis: "Is life on earth ultimately self-destructive."
[applause]
>> Peter Ward: Hank you. Great to be here. I've done several of these book talks at Microsoft.
It's always been fun. Although in the past they used to have these huge food spreads and you'd
sort of sit there and feed yourself and just get into a nice snooze, hunker down and listen to that
talk and eat some more. But that's okay. I won't fall asleep. I'm drinking tea and I'll try to make
sure you don't either.
This has been a fun interesting book to have to deal with. Medea, of course, was Jason's wife.
Jason of the Golden Fleece, and Jason apparently had only one really great gift, and that was he
could make any woman fall in love with him. So off he went and seduced the daughter of the
King of Colchis where the fleece was, ran off with her, after he ran off with her, after he had no
more gifts, everything went predictably downhill, he ran off with another queen so she ended up
killing Jason's kids and in so doing gave herself the worst-mother-of-the-millennium of the forever
award for planet earth. So tongue in cheek I decided if we had to have an alternative to Gaia,
why not go with Medea.
Although a friend of mine after I gave this talk, Medea at least had forethought, she picked up that
knife, she was thinking about this. And what I'll try to show you is evolution doesn't have
forethought. In fact, evolution appears to be this great bumbler and so he was thinking we should
really call it the "Mr. Bean hypothesis" or go somewhere there.
Two weeks ago I had the interesting experience of being on the Art Bell show, Coast to Coast, for
11 hours starting 11:00 at night and going to 2:00 in the morning. I used to listen to this driving
across deserts in my undergrad days, out in the middle of the desert you can hear Art Bell. I
literally had people calling up asking if Medea had anything to do with world governments and
black helicopters, and chem-trails which I had never heard about, these are like contrails, well,
these people think that some people are putting poison in the contrails of jets to poison us. It's
called "chem-trails."
I'd never heard about this.
Those are really Medeans -- and let's sort of launch into this and ask how "Medean" are things.
So today's presentation and now tonight, we'll talk a little bit about Gaia versus Medea, talk
mainly about evidence or deep time and also how deep time can help us perhaps predict the far
future and talk about the greatest danger for the near future.
So Gaia is really an interesting phenomenon, because it began as a hypothesis. It's adherence
within 10 years elevated it to a theory. It also became a religion along the way. It did spawn
some very useful science, a whole discipline as a matter of fact called earth system science.
Earth system science now looks at the way elements move through the various reservoirs of the
planet, the atmosphere, the rock reservoirs, the oceans and life and in and out.
So forever we should be grateful to the Guyians for at least starting what really is a legitimate
area and every earth school -- every science school in the country now has an earth system
science course.
The genesis is very interesting. Lovelock was a great atmospheric chemist. He was working for
JPL in NASA. Now, he was given early data on the Martian atmosphere, and these data were
gathered from earth instruments, and he was asked to predict if there would be life on it. And he
looked at these data and he said, nope, there's no life on mars. This is 10 years before Viking.
When Viking landed he had a big "I told you so." And the reason he did, he was simply looking at
the nature of the atmosphere and said that the Mars atmosphere is in equilibrium with its rocks,
its physical state is in equilibrium, whereas the earth's atmosphere is out of equilibrium. Meaning
that if all life on earth were to die out today -- it's kind of like that stupid program, "The Earth
Without Us," as if we're all going to go away, right -- he says if the life were to suddenly go away,
the atmosphere changes rapidly to something else, it moves back towards equilibrium. So life
keeps our atmosphere in a state that it would not be without life. And Mars didn't show any
evidence of that.
So the major aspect of Gaia is that there's homeostasis, that life really does something
interesting. It has pretty much, in his terms, it has its hands on the knobs and the dials, the active
control systems, as it were, to maintain what he calls homeostasis, and the homeostasis is a
continuity of those factors which help life stay alive. So life essentially is keeping the planet good
for life.
And there's a lot of different versions, and really the most important one is No. 3 down here,
"Optimizing Gaia." And this is the one that Lovelock still continues to push, that the biota
manipulates the physical environment for the purpose of creating biologically favorable or optimal
conditions.
Now, 1 and 2, "Influential" and "Co-Evolutionary," I mean, nobody doubts this, the fact that life
influences the rocks and the rocks influence life. They're kind of meaningless.
Number 4 is the most extreme form of Gaia, "The Earth is Alive." Nobody uses the term "yikes"
anymore. A friend of mine just said, "yikes!" So this is a good yikes.
So optimizing is really where you can start testing stuff and there are predictions that can be
tested. We ought to look at biomass through time. If Gaia is correct, then we should see a rather
continual or some sort of increase in the biomass, that's the weight of living organisms on this
planet. Not diversity.
Now, biomass and diversity may be coupled; they may not be. I'll make an argument that they're
not coupled. But certainly biomass through time should be a prediction. Secondly, we should
see that the vast majority of feedbacks, feedbacks dealing with systems that affect life should be
negative. In other words, if it gets too hot, there should be some system that cools it down. Too
cool, some system that warms it up. Too little oxygen, some system that brings up oxygen, and
vice versa. Negative feedbacks are an important part of the Gaia hypothesis.
A third important prediction is that the life span of the biosphere will be extended by life. Why
would the biosphere stop being good for life? Well, our sun continues to enlarge in the sense,
more and more energy is coming out of it every second. It is 33 percent more energetic, there's
33 percent more energy hitting the earth from the sun now than there was at the start of our solar
system 4.6 billion years ago.
So that increasing amount of energy certainly affects the effect of life and we should expect then
that life is going to do something to deal with that little phenomenon.
Finally, nature will save us, and Mr. Lovelock himself is coming to Seattle on the 15th. I'm trying
to worm my way in to hand him one of my books.
It will be one of the moments from "It Burns." At least I hope that moment happens. His point,
and he recently said that humans are an infection and that we will go from 6.5 billion down to a
half billion in the next 50 years. That's a heck of a mortality. Six billion people dying out in the
next 50 years but this is his point.
He said the Gaia of the earth is going to rise up and disinfect us, we humans. Rather extreme
point of view, and I thought I was kind of dour. Let's think of the atmosphere. There's a couple of
aspects of Gaia that are interesting here. This is one of the quotes: "The life of the biosphere
regulates the climate and the atmospheric composition." Two different things. To me the
atmospheric composition is very interesting if we're trying to look at the amounts of carbon
dioxide and the amount of oxygen in the atmosphere. And then he has this interesting quote
about being "the fur of a cat" and all that stuff, whatever.
Now, we're talking about earth. Which earth are we talking about because NASA and everybody
else is looking for earth-like planets. But an earth-like planet, but really I think we're talking about
earth right now. This earth that we're sitting in on this beautiful afternoon. Why don't we go
outside and do this over a beer. But we're in here today.
We've got this beautiful earth, right? What about right before the dawn of the Ice Age; is that the
same earth? How about 100 million years ago, the Cretaceous, that's a really different earth, or 2
billion years ago. When we talk about earth-like planets we're talking about today's earth-like
planet. Our planet itself has evolved from unhabitable to habitable and many varieties of
habitable; habitable for microbes but not animals.
We've got these various levels and the definition of what is and what isn't really needs to be
better defined, I think.
So some of the really important aspects of Gaian effects are shown here. This might be the
single most important is this examination of temperature. Here we have start, 4.6 billion years
ago. The earth system is formed in through here. It starts out really hot because of all the
condensation and the compression of the various material. But very quickly it cools down and
then, because of the sun's luminosity, it goes up, up, up, up, up, up, up, but there is a difference,
it turns out, between what it would be and what it is. And that what it is, is thought to be the
aspects of the Gaian system. And what we're looking at in through here now are ways that life
has reduced a very high temperature to keep it habitable.
Now, if there were no atmosphere at all, the temperature would be radically different, it would be
very cold. But once you have an atmosphere you've got some problems because of greenhouse
gases. So the greenhouse gas problem is being taken care of by life. However, what I'd like to
point out here is we have some of these sudden shifts. Here's one down. Here's one up. Here's
one down. Here's one up. Little blip here.
Every one of those shifts, it turns out, are correlated with major biosphere reduction in the amount
of biomass, but secondly a whole lot of extinction. We'll talk briefly about those.
So the evolution of oxygen in the atmosphere is obviously of prime interest to we oxygen
breathers. There is no such thing as an anoxic animal. And in fact David Catling of the UW
suggested that every habitable planet that wants to move to complexity will have to have an
oxygen atmosphere because oxygen is the only really oxidizing material that you can use that
gives you enough energy to be an active animal.
You could be a microbe. But if you really want to have movement, to have movement is
complexity, you're going to have to have oxygen, and our oxygen did not come packaged with the
planet when it first started. In fact, for the first two and a half billion years there was almost no
oxygen on the planet at all.
However, life invented a couple of really neat new tricks one of which was photosynthesis and
with that free oxygen began rising in the earth's atmosphere. Now, for a long time every bit of
oxygen as soon as it was produced was immediately consumed through reduction of reduced
minerals such as iron. We had these beautiful iron-rich seas, they oxidized. We had this rusty
ocean for a long time. But we eventually used up all that stuff and oxygen rose. And when it did
rise it created the probably the single most devastating mass extinction of ever because all life up
to that time life was anoxic. Sulfur reducing material, methanogens, these particular organisms
die in the presence of oxygen. Only a small select few survives this first initial rush of oxygen.
We don't have a fossil record indicator of this mass extinction but chemically we can show it's in
all probability the case.
So this was probably the most devastating event in earth's history and it is life-produced.
Now, oxygen through time itself is a very interesting topic. This is the oxygen curve above and
the carbon dioxide curve below, for the last 600 million years. Here's 600 million years ago -sorry that the slide, isn't very clear -- 450, 300, 200, 100 million years ago, and we're not seeing a
constant oxygen level. Instead we're seeing a very interesting new set of data. Here. 300 million
years ago oxygen levels in the atmosphere appeared to be about 30 to 31 percent compared to
21 percent today. That's a whole lot more oxygen. Now, oxygen is a really toxic substance, as
we know. You need oxygen to burn up stuff. But oxygen also let's you do certain things at high
levels that otherwise you can't.
I was a kid of the '50s. I grew up with the great science fiction movies and my favorite was
"Them," giant ants in the sewers of Los Angeles. May making those models must have been
cool. They're kind of like bulldozers with ant feelers and making really strange noises if you've
seen it. So somebody's pulling on the levers. But real giant insects did occur 300 million years
ago and they occurred only because of this really high oxygen. Respiration in insects is through
diffusion through tiny holes in the carapace, and unless you have very high oxygen you can't pull
enough oxygen in to support a big body.
So we have some pretty good evidence that there was very high oxygen then and just as things
go up, it crushed back down. And the end Permian and the Triassic were at times the lowest
oxygen in earth's history and in the previous book I've suggested that dinosaurs were the most
consummate respirers in low oxygen of any animal that ever lived.
And in fact, dinosaurs appeared, first of all, because of low oxygen. The whole bird system, any
bird sitting here gets 30 percent more oxygen than you or I do because they've got this really
interesting one-way system. We breathe in. It sort of gets mumbled around in our lungs and
breathed back out. A bird has a tube where it never reverses and has a second auxiliary set of
lungs called air sacs. Dinosaurs evolved in the low oxygen system as a consequence of dealing
with very low oxygen. So oxygen has gone up and gone down and it has had consequences.
But more consequential is the curve below, carbon dioxide through time, because carbon dioxide
through time being the greenhouse gas that it is, really affects the rest of life. And what we're
looking at here is high C02 and then this huge crash.
And that crash brought about the longest glaciation in earth's history, a hundred million years of
glaciers. It ran back up again and then it crashed again until we're right down here at the present
day.
This was really cold and in cold it also caused a great deal of deaths, and we'll get to that in a
little bit.
So the Medea hypothesis, evolution really is a dumb blundering process, and I was castigated for
being unkind to women for going after bad mothers. Why can't it be the bad father hypothesis.
We do that next week. New evolutionary innovation is likely to kill off incumbents as well as
making anything more optimal. Life appears to reduce the life span of the biosphere and again
maybe Mr. Bean.
But here again are some testable hypotheses especially dealing with biomass through time and
the lifespan of the biosphere.
So here are some predictions: That life should ultimately reduce longevity of any planetary
biosphere. We'll go into this as to why. It's happening on earth because of the wholesale
removal of carbon dioxide. I showed you that one graph where it dipped way down. That was a
consequence of the first forests. What could be greener and nicer than the evolution of forests.
Well it almost tipped life into mass extinction killing off everything.
So there you go, dumb blundering. We're going to hit 10 parts per million and we can predict this
from a variety of means. When that happens, that's the end of the age of animals.
We can predict that the age of animals is halfway over. We've got as much time for animals on
this planet as we've had unless somebody with intelligence evolves and starts engineering things.
That should be us. So loss of oxygen happens 20 billion years after you lose your plants and
plants will die at anything less than 10 parts per million C02. So to me the only out is the
evolution of intelligence, that this should happen on any planet and unless you get intelligence,
your planet's cooked.
So that is both a very scary but a very hopeful solution. Now, in terms of planetary engineering,
this is two of the scariest things I can think of. But this is the single scariest thing I can think of.
Paul Crutzen who got the Nobel Prize wants to seed the atmosphere with sulfates. He wants to
produce mini volcanos and send up big jets everywhere, dump out just untold tons of sulfur into
the atmosphere. This sulfur aerosol will do what a volcano does, it will reduce the transparency
of the atmosphere, sunlight would be reflected back into space and the planet itself will cool.
Now, this is a real proposal for real problems because he's very worried about the heating of the
planet. What it does do, it reduces crop yields and, secondly, it vastly increases acidification of
the oceans. All lakes will totally be out.
So this is such a blunt instrument, terrible scary thing, it's not the sort of engineering that I would
advocate to deal with such fixes.
So let's look at a couple of Medea events in detail. I want to talk about the snowball earth, the
time that the earth -- question?
>>: [inaudible] used to maintain C02 levels; now we're all about reducing it.
>> Peter Ward: Give that man a Ph.D. Exactly. It's the ironies of ironies. In the long-term we
have to maintain C02. Our job is to reduce it short-term, maintain it long-term. It's really simple.
Simple to talk about. But it's absolutely -- you're absolutely correct. It's all about maintaining
long-term C02. Keep it above 10 parts per million and we can live forever. Well, we can live until
the sun goes red giant in seven billion years.
So the future end of animal life on earth and microbial mass extinctions, let's look at these. The
snowball earths were very interesting. These happened at 2.5 billion years ago and about
.7 billion years ago. These were times when the earth froze from pole to pole. They did so
because life evolved this method of photosynthesis and in so doing it pulled all of the C02 out of
the atmosphere very quickly and froze the place. Pulled the greenhouse gasses out. We got out
of them after 20 million years because volcanic C02 finally rose to levels that heated it up and it
could melt it.
So this happened again twice, two times when great breakthrough innovations in photosynthesis
occurred, when life figured out better ways and quicker ways to get C02, we crashed into these
glaciations, and the third time is when I showed you in the Carboniferous in the giant bug time
when the forests figured out how to use and get more C02 out of the atmosphere and blundered
into these very bad patches.
Ice sheets and glaciers are a great thing to have today but if they cover most of the planet it really
reduces your biomass. And when we had these frozen planets where the oceans themselves are
covered, then life must have been reduced to a trickle.
Probably it existed only around the volcanic vents we would have tiny biomass during the
snowball and very close to planetary life extinction. These were very dangerous things to have
happen.
Lots of things died out in the Pleistocene extinction, it too was caused by life. We can blame all
the ice ages on reduction of C02 because of life properties. So the effects of the snowball would
have been a huge reduction of habitat area, a huge reduction in biomass and certainly would
have been great mass extinctions of not just species but just the quantity of life would have
plummeted enormously.
Let's look at the mass extinctions themselves and this is the area of research I've been working
on for a lot of years. We all started out thinking that they were caused by volcanos blowing up,
because again in my 1950s movies the dinosaurs would all run through that movie and did
whatever they did, you saw Raquel Welch, all that happening, and then some volcano
symbolically blows up and either the lava gets them or whatever, dies, so it must have been
volcanos. In 1980 that all changed of course with the Alvarez discovery of an impact layer.
Here's one shown here, Stevns Klint in Denmark. The very thin red line there is a layer of
iridium-shocked quartz and extra-planetary material. A lot of that is the crater, the Chicxulub
area. But you see a nice chalk. The chalk in through here is a beautifully rich sea bottom, a late
Cretaceous sea bottom. The white stuff are the skeletons of tiny plants, coccolithophorids, which
have fallen to that sea bottom. But above that thin red line there's no white stuff because the
plankton is almost totally exterminated and this is the effect of a large body impact on the planet.
Afterwards though, at the top of this picture, in about 10,000 years, it goes white again. The
coccoliths are repopulating the seas, they're almost entirely new species, but life comes back. It's
kind of what will happen when Seattle is hit by that 9 earthquake? There's the little red line. All
the buildings go to the ground, and the survivors running around. FEMA comes in, puts
everybody back up and here we go again, we're fine.
You can think of an asteroid impact as one of these bad earthquakes and those who survive are
wonderful. So obviously this had to be a truth because Hollywood made two movies about it and
there is a grain of truth to this. But it became so pervasive as an idea about extinction that we
soon by 1990 blamed all the mass extinctions on impacts. In fact I gave a talk on NPR just two
weeks ago from the origins -- three weeks ago ASU with Ira Flatow and a science reporter came
up and said, "You're totally wrong. We know every one's caused by impact." And I said, "well,
not really." So let's look at maybe what they are.
Certainly things come down from space and hit us. But the sense was on that very bottom down
through here that we could compare and correlate crater size to how much stuff dies off. So
here's the sense that the size of the impact is up through here. The size of the crater it produces
here. And the effects of it, devastates life on a continent, devastates world agriculture, most
species go extinct. How often you might expect those in terms of the understanding of
earth-crossing asteroids and materials that could hit us.
So the big events obviously become more and more rare but nevertheless, they're frequent
enough that one could expect that every 500 million years you should have five of these things.
Now, coincidentally there were five mass extinctions in the last 500 million years, so it seems to
make really good sense.
So this was the type of diversity through time curve. 600 million years ago, we're looking at the
Cambrian explosion. These are just animals. Rise of animals. We had a constant amount
through the Paleozoic and about 250 million years ago this huge mass extinction arrives, another
mass extinction, and this is the impact event, and of the other big five how many really were
caused by impacts? The slides are really an excellent sense of how really qualitative we
paleontologists are, the big five; one, two, three, four, five. We're good with numbers.
So let's look at some of these. There are big holes on this planet. This is the Manicouagan
crater in Quebec. It's well dated at 214 million years ago. That's a 100-kilometer crater. Going
back to that 100-kilometer crater on this, most species go extinct. This is what this prediction is,
the Manicouagan crater should have resulted in most species going extinct. We used to think
that this extinction, this Triassic extinction here was caused by that. However, that extinction is
200 million years ago. Our data is getting better and better and better, and this is 14 million years
before it, and so part of my job with UW is to track down rocks of this age and we did this in
British Columbia, Nevada, Europe, and nothing goes extinct. You've got a big crater on the
planet and nothing goes extinct. Not even a single species we can find goes extinct.
So there's got to be a threshold event. We know that the Chicxulub, the dinosaur-killer is 225
kilometers, and there's a whole lot more energy to produce in a 225-kilometer crater than a
hundred. But somewhere between 100 and 225 the effects scale up to kill off a lot of stuff.
But what that means is we don't have very many of these impact extinctions. So let's look at a
few places where we have worked. This the Karoo Desert in South Africa, an area where we
have the limit between the Permian and the Triassic, which is the biggest of all mass extinctions,
as many as 90 percent go extinct compared to about 60 for the dinosaur killer. This is older, 250
compared to 65 million years ago and it lets us look at a number of aspects. Beautiful stuff. I got
to work out here in the Karoo Desert for 10 years collecting some of these things, big
Gorgonopsians, this is the biggest carnivore at the time.
That's about an eighteen-inch skull, so it would have been about an eight-foot animal.
And those who watched TV, and I know nobody here does, there's a new BBC show called
"Primeval" and it's pretty cool. It's actually about this hero paleontologist and he's really great
looking, gets the girl, and that never happens in real life. And he somehow has these strange
little holes where these big nasty creatures fall through. So the first episode, one of these things
falls through this hole into a supermarket in London. It was pretty peculiar to see what they have
in supermarkets in London but then to see this big creature jumping from aisle to aisle and
jumping over aisles and he picks up a car and throws it at our hero. So I loved it. It was great.
Not realistic but pretty cool.
Other big stuff is out there. This is my son Patrick being used for scale. Hold still.
Big stuff. 250 million years ago it goes extinct. And this is a huge terrestrial extinction. This is
what the world was supposed to have. These are mammal-like reptiles. These are all your
ancestors. All those dinosaurs, they were never supposed to happen. Should have never
happened. We could have had mammals on the planet 160 million years earlier. We could be all
the way to well beyond Alpha Centauri and somewhere out to Orion by now if we only got rid of
that whole age of dinosaurs, but, oh, no, along comes the big mass extinction and for four or five
years, from 2001 to 2005, it was thought to be caused by impact, big impact. Except that didn't
happen.
So let's do a bit of chemistry. What we find now in every one of the big mass extinctions except
that of the Cretaceous are what we call chaotic carbon episodes, oscillation between Carbon 13
and Carbon 12.
What you know about Carbon 14 is dating but it turns out that Carbon 13 to Carbon 12 ratios tells
us an awful lot about productivity in photosynthesis. When there's a whole lot of photosynthetic
plants out there doing their little deal, they use up way more Carbon 12.
If you've got a lot of Carbon 13 sitting out there, the reason you get more of it is plants are really
working really hard. So conversely if we start finding more and more Carbon 12 in our analyses,
it means that somebody's killed off the plants.
And so we have begun looking at various of these mass extinction boundaries, and this is, I
know, a nasty slide, but we can go through it. So here's that ratio. Any time it goes this direction,
death is stalking the planet. All kinds of plants are dying out.
It goes this way, photosynthetic activity's gone up, biomass goes up, biomass goes down.
Biomass goes up, biomass goes way down; up, down, up, down.
This isn't like an earthquake that knocks the city down. This is like an earthquake, an
earthquake, an earthquake, an earthquake, or an impact, an impact, an impact, an impact, except
there's no evidence of impact anywhere.
Something has caused one, two, three, four, about five major shocks to the way carbon moves
through between living and non-living in such a way that we know that we have eliminated land
plant life one, two, three, four, about five times, in a period of five million years.
And then it goes back the way it was before. No swings. And down here, no swings. This was
really a shock when these data started getting pulled out of the earth, because it's unlike anything
that we had seen before, does not conform to any known mechanism that we had going, and
required to be explained.
Now, one way that we finally got at this was to think of a new way of understanding what fossils
are present and this is through a method called biomarkers. Here's our tree of life. And it turns
out that cell walls contain lipids that are really tough molecules. And that some specific lipids are
specific indeed to major groups, major branches of the tree of life. Here's our three domains:
The bacteria, the Eukaryans and the Archaeans and when we come up with some very specific
groups, there are long-chain carbon molecules that are entirely specific to that group.
Gram-positive bacteria produce this immense thing. Green sulfur bacteria produce this one,
isorenieratane. Cyanobacteria produce others. We can get green plants, we can get animals, we
have these biomarkers. And the beauty of these is that unlike fossil skeletons, you can get it from
very little material as long as you have any organics within your sediment. What you're really
looking for is oil. You're going to ancient oil from various aged rocks. If you have any
hydrocarbon at all you can tell what was there.
So this particular mechanism began to be used by paleontologists and geochemists looking at
these mass extinction boundaries. What happens when carbon oscillates? We began to find out.
It oscillated because there was jumps in the microbial world back and forth and back and forth.
And the jumps turned out to be highly explainable.
The most interesting biomarker to be found all over the planet, it turns out, in the oceans at the
end of the Permian, are these two:
Chlorobactane and especially isorenieratane. And isorenieratane and chlorobactane are coming
from these two types of microbes: Purple sulfur bacteria and green pigmented chlorobiaceaens.
These are green sulfur bacteria. They have a very specific set of characteristics where they live.
They have to have sunlight because they're photosynthetic. So that means that if you're in the
water you got to be in shallow enough water for photosynthesis. The photo-zone might be 150
feet deep in really clear water but way shallower in murky water. Two, no oxygen. You have to
have shallow water with no oxygen. That's hard to do in the world's oceans. As a matter of fact,
you can't do it anywhere in today's oceans. Three, the water has to be saturated in the poison
hydrogen sulfide. If you have H2S-rich water with no oxygen and lots of sunlight you can get
these biomarkers.
That's a really nasty combination. And we find this in every ocean at the end of the Permian.
And we've begun to find it in every ocean at every one of these mass extinctions. Now, the
implications of this are scary, really scary and we'll see exactly what it means.
This is from the Black Sea. And it really was a purple oceans. This is coming up from about 15,
20 feet deep. The purple nature of the water is because of these purple bacteria. This poor guy
is gagging because of the smell coming out of the stuff. So this is zero-oxygen water filled with
these microbes, and it's absolutely filled with hydrogen sulfide. Hydrogen sulfide is that
rotten-egg smell. There's a reason it smells so bad to us because it's very, very poisonous.
So in 2005, my colleague Lee Kump came up with a new hypothesis for mass extinction, that
there would be a buildup of hydrogen sulfide on low-oxygen bottoms, the deep bottoms of the
oceans.
But if there were a mechanism by which this low oxygen layer called the chemocline would rise to
the surface. Once you're in the photic-zone you should allow these purple sulfur and green sulfur
bacteria to start blooming. They don't make hydrogen sulfide; they eat hydrogen sulfide, but
because of their biomarkers they tell us when zero-oxygen hydrogen sulfide water was at the
surface.
Now, the kill mechanism is once you get that stuff at the surface, the H2S leaks out, and H2S is
highly toxic to marine invertebrates, to land plants, to marine plants, everything. Two hundred
parts per million kills us dead. Two hundred parts per million reduces the ozone layer to zero and
so you start getting UV and UVV smashed into the earth and the fossil plants from that time show
exactly this. We see deformations in the various spore formers indicating high UVV. Here's your
kill mechanism. High temperature, low oxygen, H2S, and H2S poisoning you need less and less
H2S poisoning as oxygen goes down and temperature goes up.
Nasty. This may have happened more than 10 times in the past.
Why did we get low oxygen sea bottoms? We'll get back. Let's look at one more that we've been
working on. This is where I will be in about five weeks, the Devonian Reef in Australia, the
Canning Basin. You can think of this if you've seen barrier reefs, you'll be able to see in here, but
off in the distance you see it kind of wiggling back and forth. This is the reef itself. If you're a
diver, deep water is out there. This is all the lagoon, the shallow-water stuff, your reef wall. The
best place for diving is right in front of that. This reef is 360 million years old. It has never been
changed or perturbed.
Now, we're down on the water. This is a crocodile-rich river but they're freshies so they don't hurt
you unlike the salties which will eat you. And here we have lots of corals right up to here and
then above here no corals at all. The reef continued to grow, but the formation of calcium
carbonate was made by microbes. All animals died off right about here. And they're replaced by
calcereous-skeleton-producing microbial groups. So why is that? Well, here again we find that
what has happened, these are corals, these are nice humpy corals, we have some nice animals
through here, and right above them, these rocks are actually under fresh surface, pure black and
black and black, and these are short episodes when zero-oxygen water has come up to the
surface and poisoned the animals. So the chemocline has come to the surface and, sure
enough, we find the biomarkers of H2S-rich microbes present here.
So this coral reef is as shallow as you can get in the world and we have these chemoclines
coming up and killing off this particular reef in one of the big five mass extinctions, the Permian
event.
So purple ocean. Indeed it would have been. And perhaps during the entire Proterozoic from 1.8
to 1 billion years ago, the oceans would have been purple. The other event is that once all this
stuff started, it leaks out a solution that turns the sky green, And hence the title of my book before
this one.
This is horrific. It could never happen again, could it? How did it happen in the first place? Well,
what happened in the first place is that the earth, on occasion, produces very short-term
moments when deep earth material comes to the surface. Here's a model of the earth by a
Berkeley group in which they've removed the earth's mantel in through here. This is deep core
stuff which works its way through, takes 20 million years to get from here to here. And then it
spreads out. It's not like one single point volcano. These are called flood basalts, only have to
drive to eastern Washington to see them. The entire eastern part of the state covered by that
lava, it's one of these things.
They're short term. They only take a few millions of years, but if they're big enough and
Washington State's wasn't quite big enough, if they're big enough, the amount of carbon dioxide
that they produce causes greenhouse warming so fast that our polar regions get as warm as our
equator.
What happens then? There's your end of sailing. No sailboats because once you've got warm
poles and equally warm temperate regions, what drives winds? Temperature difference. What
drives currents? Temperature difference. With no difference there goes your currents, your
winds the oceans stop moving and when they stop moving, they lose their oxygen. It starts in the
deep ocean first because of thermal haline which is exporting shallow-surface, cold, oxygenated
water down to the deep sea. That stops. So they go anoxic first. The nasty H2S bugs grow and
eventually hit the surface.
So this has happened over and over and over again in earth history. Every one of these red
areas is one of these short-term volcanic events. The one up through here called the Siberian
Traps is the biggest, and although that huge size is pretty huge, it happened over about two
million years.
We need to look at carbon dioxide through time and see when these mass extinctions happened
and we can see they seem to coincide with high C02. We've had these peaks in carbon dioxide,
the whole world goes anoxic, the nasty H2S comes out and, boom, dead stop.
Now, you can say, well, it was the volcanoes that started it. Yes, but it's life that causes the kill.
The H2S is life-produced. This is Mother Medea at work. It's happening today. We're finding
hydrogen sulfide eruptions all along the cost in Namibia. The Skeleton Coast from Walvis Bay
right up north is rich with hydrogen sulfide, because the anchovy has been killed off through here.
Highly productive, very rich upwelling. Surface plankton dies, goes to the bottom and rots and
causes this upwelling of H2S. The thing is happening in Hood Canal. We have also found in the
last year that sea grass is no longer growing in the San Juan Islands. And this is a very scary
phenomenon which could lead to the loss of an awful lot of economically important fish up there.
All right, the new view of mass extinctions: Most were caused by rapid global warming brought
about by volcanic greenhouse emissions, stagnate oceans go anoxic, toxic sulfur bacteria take
over, finally it comes to the surface and you've got H2S. You lose your ozone, you've got direct
poisoning and what would the movie be?
So how long would the biosphere last? And we're almost done here. Extended by life, Linton, a
Gaian, suggested it is, whereas I would maintain that long-term C02, as this very smart
gentleman back here pointed out, is our biggest problem. So as we head towards the future,
we've got more and more sunshine heading at us and sooner or later we lose the oceans. But it
turns out that that particular event which I've always thought to be sort of the end of animal life is
going to come well after the death of plants.
And if we think of an earth clock, here we are now in this age of plants and animals, about
halfway ticking through, and within a half billion, perhaps at most a billion years, we're going to
lose plants. The oceans won't be lost to space until three billion years after that.
So we can think of it now. We have this long-term brightening of the sun. It's funny, it's ironic, we
know more about the far future than the near future. The physics of the sun and how it's
brightening is well known. Looking at main-sequence stars, and I like to think of the age of the
animals as this nice little Oreo filling in the two dark microbial ages; the first and second microbial
age. There's the loss of C02 again, that's really nasty, and the reason is our continents keep
getting bigger but mainly because life has gotten more and more and more efficient at taking
carbon dioxide and turning it into calcium carbonate skeletons which then get stuck on continents
and go out of the cycle. We're taking C02, you need it, and turning it into rocks. And only
intelligence can put it back in. So this is a major screw up by life.
Long-term if we look at C02, we go all the way back to three and a half billion years ago, almost
all of this long-term drop has been the increasing efficiency of life at producing limestone. Almost
every bit of limestone on this planet is mediated by life. Inorganic limestone rarely occurs.
Life-forming limestone, it just gets taken out of the systems.
That's our real problem, is that drop, is to stop that. If we look at biospheres through time,
predictions are that the greatest biosphere on the planet was somewhere between half billion and
a billion years ago. Not species, biomass. Because of high temperature, high C02, the microbial
world back then would have been unbelievably rich. If you like slime, this would have been
fantastic. Every ocean covered by goo. Huge reefs of this stuff. The land surfaces everywhere
that's wet, microbial groups. Animals have eaten all that stuff out of existence but the amount of
weight of life on this planet was in the past and every current estimate, here we are here, is that
we're heading downhill fast. This is life on an aging planet.
That's a little grim. What's going to happen is as this planet ages, we're going to see the tree of
life here, and cut it down bit by bit. The final aspect I want to talk about is the near term, and this
deals with something we all know about, the irony again, long-term C02 is our problem, but
short-term C02 rise is where we really what we have to look at. We're heading from 9 to 11
billion. We're also looking at a one meter sea level rise by 2100. You cannot stop that. And that
is the most conservative estimate. The IPCC said 59 centimeters. That's nonsensical. Totally
nonsensical. James Hanson says two to three meters. That's probably equally nonsensical.
But think what a meter sea level rise does. One meter sea level rise means the storm surge goes
up for five meters but worse than that is salt intrusion laterally. One meter up puts salt into fields
that don't have it now. One meter up suggests we may have a 25 percent reduction in food area
or at least food fields, agricultural fields by 2100. So remove a quarter of the food and increase
the population by a third, and that's pretty much what we're looking at.
So we know it's happening. It's happening really fast. We're already back to C02 levels we've
not seen in the last 20 million years, and we're rapidly heading back to C02 levels we haven't
seen in the last 100 million years. We should hit that by two centuries at the most. The rate at
which this is going on is now well documented and that curve is accelerating.
The one good news that was taking place was that comparing temperature rise in every single
continent, the only good news is Antarctica, that Antarctica seemed to be cooling. Michael
Crichton used that with Senator James Inhofe to say that global warming is a crock. But in
Nature, the cover of Nature just three months ago my colleague Eric Steig from the University of
Washington who was with me in Antarctica, I guess we came back four weeks ago, has now
shown that Antarctica is warming as well as everything else is warming and indeed it was quite
sobering to be down there. We were living in tents seven weeks watching it melt all around you.
So this is my next book. This is no joke. I think this is our biggest problem facing us is sea level
rise by far. Because last year we rose C02 2.1 parts per million. In the last three years you can't
escape global warming, we all see it everywhere, and we still went up 2.1 parts per million last
year. It's above the worst estimates for IPCC. People thought we were finally kicking in, it's
working. Well, it's not working.
The biggest effects will be in places like Bangladesh; 1.5 meter impact, for instance, affects a
gigantic land area. They feed themselves currently but they have three crops per year rotating,
and every bit of arable land is being used. But the 1.5 meter impact, again it's not the covering by
sea water -- that's bad enough -- it's the salt intrusion. Salt intrusion is where you get nailed. 1.5
meters should really thoroughly reduce the output of the San Joaquin Valley. They're already in
salt problems. We have to move the cities up. We have to move the fields up.
Can we stop it? I don't think so. Not with China producing coal-fired plants right and left. Coal is
the biggest killer. And it is not building -- is it not driving cars; it's building cars. Energy
producers, the power plants are the worst problem.
Here's California. If we went up a kilometer, we're not going to go up a kilometer but we're going
to go up a third of this. If we melt Antarctica and Greenland. Even with a third of this the San
Joaquin and Sacramento valley are flooded totally. So we've lost all that particular region.
All right. There' s a couple of extreme views here. Here's one, our final hour. Martin Reeves.
We're in big trouble, good-bye. But there's another view that what I hope to end here with is one
of hopefulness.
We see there's a problem. Like a bunch of alcoholics, number one I recognize there's a problem.
So the nice thing is that number two -- here's us in the Antarctica -- gigantic ammonite that
showed up in my lab yesterday, this is part of it. The rest of it spun the way through here.
There's no reason that our species has to go extinct. I was in Harvard a couple weeks ago. One
of the speakers said we're going to evolve out of existence quickly. No. This is the chambered
nautilus; it's been around 500 million years. There's no gene within a species like there's a gene
for aging, there's no gene for species, I'm going to go extinct. It doesn't happen. You can last as
long as you keep the things around you. It lets the planet stay inhabitable for a great long time.
Near term we have to get over the C02 bulge and global sea level rise that's going to happen.
My sense is we're not going to stop the melting of the ice caps, the ice sheets. They're going,
because we're trying to bring the rest of the world up to our standard of living. To do that, the
only fuel to do it is going to be coal.
And no matter if we took every bit of energy in this country, India and China are just going to keep
burning coal. They're just not going to stop. So then what do we do? How do we mediate? How
do we make it the least amount of mortality over the next few centuries? And that is the
challenge that I think we all have to confront. I have an 11-year-old kid. I don't let him go to
these talks. He gets too scared. Scares me, too.
All right. The irony I'll leave you with, I think we're the only guys on the planet that have the
capability of being. There is no Gaia. There's a lot of Medeans going on but if we want to
change it and fix it, we have to be Gaians. With that I'll stop. Thank you.
[applause]
Questions, there's one.
>>: Probably won't be as intelligent as his. But one thing I'm curious about, it's only partially
related to what you were saying, you would be doing this research anyway even if the Gaians
weren't out there with their nonsense, because this is the work you do. Because if you spent time
interacting with, trying to talk to those people, and what I've never found or understood is do you
feel like you have any way to talk to them where they slowly come to their senses? It always
seems like it's absolute noncommunication.
>> Peter Ward: I haven't talked to anybody. I've never talked to a group that didn't already
believe my point of view anyway. I write these books. Who buys these books? Look at this
audience. This is not the real world. I mean, let's face it. You're not the -- where I live, the
University of Washington, this is a different species of not-the-real-world.
So when I go on Art Bell, that's the real world. And they call me up and say that helicopters,
black helicopters are flying over or they have aliens in their freezer. But what they don't do is buy
books.
I've got Amazon right on there. I'm looking at the instantaneous Amazon book deal while I'm
giving this talk. If you buy one, it rises hundreds of thousands. Nothing happens.
So I've decided I'm going to do -- I'm doing TV. I have a show called "Animal Armageddon." It's
on the Animal Planet. It's the mass extinctions meet dinosaurs, right? That was fun. Nobody
watches that.
So now I have a new -- I'm going to make video games. No, I'm serious. How do you get the
teenagers? They all do video games. What if we did a video game on a SimEarth where you
gotta build an earth where you don't cause sea level to rise. You make that technological society
without melting the ice sheets. How are you going to do it? I made this challenge to Seattle
Center. I got three people, very serious people, saying, we really need to do this, because I think
there's no other way you get to the teenagers. My son doesn't read.
He got Spore. I can't get him off the damn thing. But Spore, it's frustrating, because it's not the
real world. What if we did the history of life with real species, real dinosaurs, and the mass
extinctions and that you gotta get past this mass extinction to get to the next level. If you don't
you go back and start over.
Let's have real evolution with real species, with real things that really happen. Now, that would
be a whole lot better than taking whatever they call science classes in Seattle public schools
which has no science anyway that I can see. That's our challenge. If we want to engage this
generation we've got to do some video games. That's where they are. You've got to Twitter it to
them.
Am I wrong here? That's what they do. Right? So it's our challenge as grownups to try to
educate them in science, keep them engaged in science because if we don't produce lots of
scientists and engineers, we can't get the C02 out of the rocks. Then we're really screwed.
Question.
>>: You may have heard about Jeremy Jackson at Scripps Institute. He has a presentation
called Breaks the Ocean. He holds out much less hope even than you here and basically says
that all megafauna of the oceans will be dead within 30 years dominated by microbes, stratified
and anoxic because of the overfishing and the dead zones and the acidification, put all these
stressors together make things much worse for life in the ocean than we've previously seen in
geological history. What do you think about that.
>> Peter Ward: That's irresponsible. I know Jeremy, and that's a prediction. But it is a prediction
that leads to such hopelessness that nobody does anything. Right? If it's hopeless, why do
anything?
And you can't take that point of view. We have all these -- it's got to be somebody in here with
kids. If any one of you have kids we just cannot take this point of view. We're just hopeless.
Jeremy doesn't know that. That it's a probability, but it's not totally gonna happen.
So I just don't think we have to go there.
Question.
>>: So you mentioned something in the beginning of your presentation about negative feedback
loops, and that's -- every time I read anything about climate change and the more I go to -- I'm
very puzzled because in my -- when you study science in high school, you know, you come to the
conclusion that like if you were to encounter a system at a random point in time, in all likelihood it
would be in equilibrium, because systems don't stay in disequilibrium very long, right? So if
you've got, you know, your cone or something, you're very unlikely to walk in on it at the exact
moment when it's about to topple off, right.
And so are we just -- is it just coincidence that we happen to be a species that evolved or that the
earth evolved in this period where it was, in fact, in disequilibrium between the 500 million years
of slime to come and the several billion years of slime in the future.
This is the part that I don't understand. There has to be some negative feedback loops
somewhere otherwise this instant in time would have even been briefer.
>> Peter Ward: There are negatives, lots of negative feedback loops. But there's also lots of
positive feedback loops. One of the slides of an earlier version of this talk I listed 15 of them. It
was kind of like looking at the Manhattan telephone book with all this list of stuff.
But the feedbacks -- let's look at the temperature. The most interesting feedback on the system
of all, temperature. We've had pretty constant temperature. How does that happen? Well, if it
gets warmer and warmer and warmer it turns out the rate of weathering increases, and one of the
odd things is you take a silicate rock, like a piece of lava or a piece of granite, and you weather it,
just put water on it, it breaks down several of the minerals and the byproduct of that is a reaction
producing a rock that requires one atom of C02.
The more you weather, the more C02 you take out. So as you weather faster and faster, you're
pulling more and more C02 out of the atmosphere. But what's that do? That makes it cooler. As
it gets cooler your rate of weathering slows down. Now, volcanoes are always putting up a
constant amount of C02 in the atmosphere. If we get it too cool, it warms up. So this is a
beautiful feedback system. The warmer it gets, the cooler it gets. The cooler it gets, the warmer
it gets. That's a beautiful negative feedback system.
But what happens to ice now when we warm it? We warm it, ice melts, albedo changes, less light
is reflected, it gets warmer, we melt more ice. So that's a positive feedback system. That
positive feedback system is what we're in right now. I think we absolutely ought to wear buttons
that say "Save the Ice Sheets." That's what we have to do.
We've never had ice sheets on this planet when C02 has been a thousand parts per million,
never. We're going to hit a thousand for sure. The question is how long can we keep it at a
thousand until we bring it down before Greenland and Antarctica go. If we lose those, 240 feet. If
we lose that, all the Continental edges, all of the coastal cities, they're all gone. What happens to
humanity then? Well, we move to higher ground. It's going to be very slow but nevertheless
we're going to lose most of the regions on this planet that currently are arable, because they're all
low, very low elevation. High elevation farming is not anywhere as near as good.
One last thing. You said, equilibrium. Well, it turns out that life has kept the atmosphere out of
equilibrium for billions of years. So systems want to go back but life is here, as long as it's here
it's keeping that system out of equilibrium. So it doesn't have to immediately go back. I don't
think I answered your question but at least I ->>: How is it we have constant temperatures for millions of years.
>> Peter Ward: It's a silicate feedback system. But, again, what happened is I told you about the
first forests. Everything had been a nice constant temperature, everything was hunky-dory and
then trees evolved with longer roots.
Once they dig deeper the weathering rate went up seven times. And once the weathering rate
went up seven times, seven times more C02 got pulled out of the atmosphere all of a sudden and
temperature went crash and we built these big glaciers and we had a 100 million years of
glaciation through the Carboniferous. Oh, what a mess, because stupid life blundering. What
could be more green than making trees. You almost kill off the whole planet.
>>: We're looking for extra-solar planets. What do you think the odds we're going to find "purple"
earths before we find "blue" earths.
>> Peter Ward: Plenty. I think we'll see this system over and over. Most of our earth has been
purple. If we went back from -- the oceans were purple from 2.5 billion up to a half billion years
ago. It's almost always purple.
Here's a cool deal. Guess what I just learned? You know how fast the spin of the earth would be
if we didn't have a moon? Four to five hours. So two hours of day, two hours of night. Two
hours of day, two hours of night. What does that do to climate? Is the earth habitable? Does it
remain long-term temperature equilibrium with a four-hour spin. So a bunch of people are trying
to figure that little one out. So Kirschner at Caltech thinks, no, a fast spin, you'll go runaway
greenhouse. I don't think I agree with him yet. But everything else being equal if you're looking
for other earths and ours has 24 hours because the moon has this gravity on the oceans, it
slowed us down, a fast-spinning earth, everything else being equal, is not going to be our planet.
It's going to be different. I'm not going to say it wouldn't be habitable. But it's really not going to
be our planet. We're just trying to figure it out now.
The interesting thing about earth there's far more super-earths than earths and the super-earths
are really -- turns out earth is almost -- we're rare because we're so small to be habitable.
Super-earths with two times earth's gravity, what's that going to do to the biomechanics of all the
creatures on it. That's the cool thing; start looking at what is biology in a super-earth.
Questions.
>>: Why so much pessimism on China and India and their coal-consumption habits? Do you
think Dick Cheney is kind of in the running for the new PM of India.
>> Peter Ward: I just did a little research on it. It turns out that 1 out of 100 Chinese and Indians
have a car. So if you want to build cars, you want to sell cars, that's where you sell them.
>>: That is true. But a lot of them ride little 20CC motor scooters, that kind of thing.
>> Peter Ward: Yeah, but also if their standard of living goes to the point, like in India get the
$2,000 car, which has no pollution control whatsoever. But everybody wants a car. And it's not
the cars that screw you, it's the power plants that make the cars. You need a lot of power to
fashion an automobile, the steel and aluminum, all this stuff. That's where the power plants are
now being done.
I did sabbatical in Australia. Australia is the biggest bunch of hypocrites on the planet. Australia
does not allow coal-fired plants to be built in Australia but they export every pound of coal to
China. And it's high-sulfur coal.
I was there sitting by Sydney watching these ships, pile, ship after ship after ship, pure Australian
coal right to China.
>>: So you've outlined a lot of challenges that we have coming up. But in terms of dealing with
them, what are the things that need to be accomplished and are there any ways that you have
thought of that we could attack this?
>> Peter Ward: Yes, better living through engineering. And the engineering I'm talking about is
Craig Venter-style engineering; not bricks and mortar. It's going to be biological. The two biggest
challenging us are energy and food, and Craig Venter and his group trying to bioengineer now -he can build aliens. He's got life going with amino acids. The keys to the kingdom are just
starting to open up.
You've got to engineer -- we have to make very large shallow seas to produce lipids to the point
that these become fuel sources. Now, the trouble is that, once again, is reduced organic, you'll
put C02 in the atmosphere but at least we're getting away from digging oil out of the ground.
Let's grow it. Let's grow our energy and grow our food. These two aspects of genetic
engineering are I think what we really need to do, but beyond that we need to start growing as
much technology as possible. I mean, turn almost everything into biology. It's amazing what you
can grow.
You can, with the keys to the kingdom of genetics, you can really engineer a lot of solutions that
will help the atmosphere. And I think that's the engineering that I see this century, that's where it
has to come from. And I spent the last two conferences with Craig, one at Harvard and one at
ASU, spent a couple days with him. Somebody asked him, "You sound like you're God." And he
said, very seriously, "I am God." I don't know if you know this guy. He's really scary. But, on the
other hand, we've got to do something.
And I think this is the way we have to go. I don't think it's going to be bricks and mortar. I think
engineering, though, is what has to be done and it should be biological. Or what you guys do.
But you guys are going to end up doing biological software. You'll do biological computers. It's
all coming to that. It's just so much better than the metals. That's my guess.
Thanks for coming. Sorry to be so long and boring.
[applause]