[Transcript
of a ABC Radio National Background
Briefing program: Jared Diamond at
Kristen
Garrett: Throughout human history, societies, civilizations have prospered and
collapsed over time. The reasons, obviously, have lessons for the whole of our
intricately interlinked planet today. At
Jared
Diamond: Why did these ancient civilizations abandon their cities after building
them with such great effort? Why these ancient collapses? This question isn't
just a romantic mystery. It's also a challenging intellectual problem. Why is
it that some societies collapsed while others did not collapse?
But
even more, this question is relevant to the environmental problems that we face
today; problems such as deforestation, the impending end of the tropical
rainforests, over-fishing, soil erosion, soil desalinization, global climate
change, full utilization of the world's fresh water supplies, bumping up
against the photosynthetic ceiling, exhaustion of energy reserves, accumulation
of toxics in water, food and soil, increase of the world's population, and
increase of our per capita input. The main problems that
threaten our existence over the coming decades. What if anything, can the past teach us about why some societies are
more unstable than others, and about how some societies have managed to
overcome their environmental problems. Can we extract from the past any useful
guidance that will help us in the coming decades?
There's
overwhelming recent evidence from archaeology and other disciplines that some
of these romantic mystery collapses have been self-inflicted ecological
suicides, resulting from inadvertent human impacts on the environment, impacts
similar to the impacts causing the problems that we face today. Even though
these past societies like the Easter Islanders and Anasazi
had far fewer people, and were packing far less potent destructive practices
than we do today.
It
turns out that these ancient collapses pose a very complicated problem. It's
not just that all these societies collapsed, but one can also think of places
in the world where societies have gone on for thousands of years without any
signs of collapse, such as
What
I'm talking about is the collapses of societies and their applications to the
risks we face today. This may sound initially depressing, but you'll see that
my main conclusions are going to be upbeat.
Kirsten
Garrett: The first example he gave to illustrate the sorts of problems
communities accumulate was the
Jared
Diamond: If
Visiting
In
trying to understand the collapses of ancient societies, I quickly realized
that it's not enough to look at the inadvertent impact of humans on their
environment. It's usually more complicated. Instead I've arrived at a checklist
of five things that I look at to understand the collapses of societies, and in
some cases all five of these things are operating. Usually several of them are.
The
first of these factors is environmental damage, inadvertent damage to the
environment through means such as deforestation, soil erosion, desalinization,
over-hunting etc.
The
second item on the checklist is climate change, such as cooling or increased
aridity. People can hammer away at their environment and get away with it as
long as the climate is benign, warm, wet, and the people are likely to get in
trouble when the climate turns against them, getting colder or drier. So
climate change and human environmental impact interact, not surprisingly.
Still
a third consideration is that one has to look at a society's relations with
hostile neighbors. Most societies have chronic hostile relations with some of
their neighbors and societies may succeed in fending off those hostile
neighbors for a long time. They're most likely to fail to hold off the hostile
neighbors when the society itself gets weakened for environmental or any other
reasons, and that's given rise for example, to the long-standing debate about
the fall of the Western Roman Empire. Was the conquest by Barbarians really a
fundamental cause, or was it just that Barbarians were
at the frontiers of the
Similarly,
relations with friendlies interacts.
Almost all societies depend in part upon trade with neighboring friendly
societies, and if one of those friendly societies itself
runs into environmental problems and collapses for environmental reasons, that
collapse may then drag down their trade partners. It's something that interests
us today, given that we are dependent for oil upon imports from countries that
have some political stability in a fragile environment.
And
finally in addition to those four factors on the checklist, one always has to
ask about people's cultural response. Why is it that people failed to perceive
the problems developing around them, or if they perceived them, why did they
fail to solve the problems that would eventually do them in? Why did some
peoples perceive and recognize their problems and others not?
I'll
give you four examples of these past societies that collapsed. One is
The
second case are the collapses of Henderson and Pitcairn Island in the Pacific,
which were due to the combination of self-inflicted environmental damage, plus
the loss of external trade due to the collapse of a friendly trade partner.
Third
I'll discuss, closer to home the Anasazi in the
And
then finally I'll mention the Greenland Norse who ended up all dead because of
a combination of all five of these factors.
So
let's take then the first of these examples, the collapse of
Easter
is a relatively fragile environment, dry with 40 inches of rain per year. It's
most famous because of the giant stone statutes - those big statues weighing up
to 80 tons - stone statues that were carved in a volcanic quarry and then
dragged up over the lift of the quarry and then 13 miles down to the coast and
then raised up vertically onto platforms, all this accomplished by people
without any draught animals, without pulleys, without machines. These 80 ton
statues were dragged and erected under human muscle power alone. And yet when
Europeans arrived at Easter in 1722, the statues that the islanders themselves
had erected at such great personal effort, the islanders were in the process of
throwing down their own statues,
Well
the how, why and who has been settled in the last several decades by
archaeological discoveries. Easter Islanders were typical Polynesians, and the
cause of the collapse became clear from archaeological work in the last 15
years, particularly from paeleo-botanical work and
identification of animal bones in archaeological sites. Today
Polynesians
settled Easter, they began to clear the forest for their gardens, for firewood,
for using as rollers and levers to raise the giant statues, and then to build
canoes with which to go out into the ocean and catch porpoises and tuna. In the
oldest archaeological one sees the bones of porpoises and tuna that the people
were eating. They ate the land birds, they ate the sea-birds, they ate the fruits of the palm trees. The population of
Easter grew to an estimated about 10,000 people, until by the year 1600 all of
the trees and all of the land birds and all but one of the sea-birds on Easter
Island itself were extinct. Some of the sea-birds were confined to breeding on
offshore stacks.
The
deforestation and the elimination of the birds had consequences for people.
First without trees, they could no longer transport and erect the statues, so
they stopped carving statues. Secondly, without trees they had no firewood
except of their own agricultural wastes. Thirdly, without trees to cover the
ground, they suffered from soil erosion and hence agricultural yields
decreased, and then without trees they couldn't build canoes, so they couldn't
go out to the ocean to catch porpoises, there were only a few sea-birds left
because they didn't have pigs the largest animal left to eat with the
disappearance of porpoises and tuna were humans. And Polynesian society then
collapsed in an epidemic of cannibalism. The spear points from that final phase
still litter the ground of
I
think one of the reasons that the collapse of
I
can't help wondering what the Islander who chopped down the last palm tree said
as he or she did it. Was he saying, 'What about our jobs?
Do we care more for trees than for our jobs, of us loggers?' Or maybe he was
saying, 'What about my private property rights? Get the big government of the
chiefs off my back.' Or maybe he was saying, 'You're predicting environmental
disaster, but your environmental models are untested, we need more research
before we can take action.' Or perhaps he was saying, 'Don't worry, technology
will solve all our problems.'
Kirsten
Garrett: After speaking about several other Pacific Island nations and what
happened to them, Professor Jared Diamond went on to talk of the Anasazi, an Indian nation later called the Pueblo, in what
is now the United States.
Jared
Diamond: My next example involves the Anasazi in our
south west, in the four corners area of
The
Anasazi were ingenious at managing to survive in that
environment, with low fluctuating, unpredictable rainfall, and with
nutrient-poor soils. The population built up. They fed themselves with
agriculture, in some cases irrigation agriculture, channeled very carefully to
flood out over the fields. They cut down trees for construction and firewood.
In each area they would develop environmental problems by cutting down trees
and exhausting soil nutrients, but they dealt with those problems by abandoning
their sites after a few decades and moving on to a new site. It's possible to
reconstruct Anasazi history in great detail for two
reasons: tree rings, because this is a dry climate, the south-west. From
tree-rings you can identify from the rings on the roof beams, what year - 1116,
not 1115 AD - what year the tree in that roof was cut down, and also those cute
little rodents in the south-west, pack rats, that run around gathering bits of
vegetation in their nests and then abandoning their nests after 50 years, a
pack rat midden is basically a time capsule of the
vegetation growing within 50 yards of a pack rat midden
over a period of 50 years. And my friend Julio Betancourt who was near an Anasazi ruin and happened to see a pack rat midden whose dating he knew
nothing about. He was astonished to see in what's now a treeless environment, in this pack rat midden
were the needles of pinion pine and juniper. So Julio wondered whether that was
an old midden. He took it back, radio carbon-dated
it, and lo and behold it was something like AD 800. So the pack-rat middens are time capsules of local vegetation allowing us
to reconstruct what happened.
What
happened is that the Anasazi deforested the area
around their settlements until they were having to go
further and further away for their fuel and their construction timber. At the
end they were getting their logs, neatly cut logs, uniform weighing on the
average 600 pounds, 16 feet logs, were cut at the end on tops of mountains up
to 75 miles away and about 4,000 feet above the Anasazi
settlements, and then dragged back by people with no transport or pack animals,
to the Anasazi settlements themselves. So
deforestation spread. That was the one environmental problem.
The
other environmental problem was the cutting of arroyos. In the south-west when
water flow gets channeled for example in irrigation ditches, then vast water
flow is run off in desert rains. It digs a trench in the channel, and digs a
trench deeper and deeper so those of you who've been to
And
then in
When
the drought came in 1117 it was a couple of decades before the end. Again any
of you who have been to Pueblo Benito, will have seen that Pueblo Benito was
the six storey skyscraper. Pueblo Benito was a big, unwalled
plaza, until about 20 years before the end, when a high wall went up around the
plaza. And when you see a rich place without a wall, you can safely infer that
the rich place was on good terms with its poor neighbors, and when you see a
wall going up around the rich place, you can infer that there was now trouble
with the neighbors. So probably what was happening was that towards the end, in
the drought, as the landscape is filled up, the people out on the periphery
were no longer satisfied because the people in the religious and political centre, were no longer delivering the goods. The prayers to
the gods were not bringing rain, there was not all the stuff to redistribute
and they began making trouble. And then at the drought of 1117, with no empty
land to shift to, construction of
In
this case then, the Anasazi case, we have the
interaction of well understood environmental impact and very well understood
climate change from the tree rings, from the width of the tree rings, we know
how much rainfall was falling in each year and hence we know the severity of
the drought.
My
next to last example involves Norse Greenland. As the Vikings began to expand
over and terrorize
The
vanishing of Viking Greenland is instructive because it involves all five of
the factors that I mentioned, and also because there's a detailed, written
record from Norway, a bit from Iceland and just a few fragments from Greenland:
a written record describing what people were doing and describing what they
were thinking. So we know something about their motivation, which we don't know
for the Anasazi and the Easter Islanders.
Of
the five factors, first of all there was ecological damage due to deforestation
in this cold climate with a short growing season, cutting turf, soil erosion.
The deforestation was especially expensive to the Norse Greenlanders because
they required charcoal in order to smelt iron to extract iron from bogs.
Without iron, except for what they could import in small quantities from
So
problem No.1, ecological damage, problem No.2, climate change. The climate in
Fourthly,
there was the cut-off of trade with
So
there were cultural factors also while the Norse refused to learn from the
Inuit and refused to modify their own economy in a way that would have
permitted them to survive. And the result then was that after 1440 the Norse were all dead, and the Inuit survived.
There
are a series of factors that make people more or less likely to perceive
environmental problems growing up around them. One is misreading previous
experience. The Greenlanders came from
Problem No. 3, short time scale of experience. In the Anasazi
area, droughts come back every 50 years, in Greenland it gets cold every 500
years or so; those rare events are impossible to perceive for humans with a
life span of 40, 50, 70 years. They're perceptible today but we may not
internalize them. For example, my friends in the
Fourthly
the Norse were disadvantaged by inappropriate cultural
values. They valued cows too highly just as modern Australians value cows and
sheep to a degree appropriate to
Finally,
why would people perceive problems but still not solve their own problems?
A
theme that emerges from Norse Greenland as well as from other places, is insulation of the decision making elite from the
consequences of their actions. That is to say, in societies where the elites do
not suffer from the consequences of their decisions, but can insulate
themselves, the elite are more likely to pursue their short-term interests,
even though that may be bad for the long-term interests of the society,
including the children of the elite themselves.
In
the case of Norse Greenland, the chiefs and bishops were eating beef from cows
and venison and the lower classes were left to eating seals and the elite were
heavily invested in the walrus ivory trade because it let them get their
communion gear and their
Whereas in much of the rest of the world, rich people live in
gated communities and drink bottled water. That's increasingly the case in
Well,
finally then. I've talked mostly about the past. What about the situation
today? There are obvious differences between the environmental problems that we
face today and the environmental problems in the past. Some of those
differences are things that make the situation for us today scarier than it was
in the past. Today there are far more people alive, packing far more potent per
capita destructive technology. Today there are 6 billion people chopping down
the forests with chains and bulldozers, whereas on
Another
big difference between today and the past is globalization. In the past, you
could get solitary collapses. When
Kirsten
Garrett: That was Professor Jared Diamond from UCLA, speaking at
Man:
The impression I get is that you are talking about them primarily in relation
to environmental factors, you're talking about an
elite that becomes isolated, insular and operates without being affected by the
consequences of environmental degradation. What about other cultural forces,
such as the development of political instability, civil wars, people who are
low down in the hierarchy that are challenging the order. And could it be the
societies simply over time devolve towards political instability. What about
other factors such as disease for example, could they play a role as well?
Jared
Diamond: Absolutely. In two minutes I did not do justice to cultural factors.
There's a large literature on causes of instability and civil wars and collapse
of States and civil unrest, and it turns out that you will go home and say
Jared Diamond has a list of eight explanations for everything. There are eight
variables that people have been able to identify: With risk of civil war, for
example there's a data base of all cases of State failures and civil wars and
violent government transitions in the last 30 years. People have mined this
data base. Would anybody like to guess what is the single
factor that is the best predictor of the collapse of societies in the last
couple of decades? This is an unfair question because it's so
surprising. The strongest predictor is infant and child mortality. Countries
that have had high infant or child mortality are more likely to undergo State
collapse, and there are many links, including difficulties in the workforce,
high ratio of children to adults. But in brief, yes, there is a large
literature of other cultural factors that contribute to the collapse of
societies.
Woman:
Talking about culture problems, is there any correlation between the level of
conservatism in a society and the likelihood of it collapsing?
Jared
Diamond: I don't know. This is something that we haven't measured, we haven't
tried to measure. Interesting, but I don't know.
Kirsten
Garrett: The next question was not miked, so
Professor Jared Diamond responded and restated it.
Jared
Diamond: Interesting question. For those of you who didn't hear it: Do I think
that today there's more reliance that technology will come and somehow save us,
even though we can't specify how? Yes there certainly is, and many of my
friends, particularly in the technology sector don't take environmental
problems so seriously. I'll give you a specific example. After Guns, Germs and Steel was published, it
was reviewed by Bill Gates who liked it and gave it a favorable review, and the
result was that I had a two-hour discussion with Bill Gates, who is a very
thoughtful person, and he's interested in lots of things. He probes deeply and
he has seriously considered positions of his own. The subject turned to
environmental issues and I mentioned that that's the thing that most concerned
me for the future of my children, Bill Gates has young children. He paused in
his thoughtful way and he said, not in a dismissing way, 'I have the feeling
that technology will solve our environmental problems, but what really concerns
me is biological terrorism.' Look that's a thoughtful response, but many people
in the technology sector assume that technology will solve our problems. I
disagree with that for two reasons.
One
is that technology has created the explosion of modern problems while also
providing the potential for solving them. But the first thing that happens is
technology creates the problem and then maybe later it solves it, so at best
there's a lag.
The
second thing is that the lesson we've learned again and again in the
environmental area is it's cheaper, much cheaper and more efficacious to prevent
a problem at the beginning than to solve it by high technology later on. So
it's costing billions of dollars to clean up the
[Found
at oilcrash.com.]