Wk+02+-+Narrative

Storyline 2 This is the script that will be read by Dr. Hartwell with the following images flashed up on the screen. __ Imagination __ No other species has been able to live in all the world’s environments except humans.



No other species has learned how to cultivate its food so that only 1% of its population can produce enough for everyone.

No other species has created ways to transport itself around the world in a day or communicate with everyone else on the planet at the speed of light. Humans are nature’s unique experiment with social imagination. Other species are intelligent but humans can imagine a better future, discuss it, and create it. And herein lies both the cause of our problems and their possible solutions.

__ Science __ All living organisms on earth depend for their success on exploiting the regularities in nature – night and day, the seasons, the behaviors of their predators and their prey.

But no species is as obsessed with discovering nature’s predictability than humans.

We not only predict sunrise but we have measured the speed that light travels with a precision of 186,000 miles a second. We not only know that nearly all of the earth’s energy derives from the sun but we know the nuclear reactions that produce that heat and can predict when the sun will burn out. When the sun burns out, it will take us eight and one half minutes to notice since that is how long it takes the light from the sun to get to earth. This is science. ( from <[]> )

You have all had some exposure to science and it probably seems pretty complicated to you. That is because after hundreds of years of measuring things we know quite a bit. The details can be overwhelming. I think we can make it relatively simple for our purposes. We do need to appreciate what science can do to help solve our sustainability problems and what it cannot do.

__ Rules __ It is important to separate two concepts, scientific rules and metaphors. At its most fundamental level science is about measuring things, seeing how reproducible they are and then making predictions about the future. It is all about quantitative prediction. **__Quantitative prediction__** refers to the structured investigation of things and their relationships. This process relies on measurements, data, and mathematical models that connect and empower the theories and hypothesis behind what one is researching. What is amazing is that our universe follows very strict and reproducible rules and those rules are obeyed throughout time and space. We can predict with great precision the occurrence of eclipses for many years into the future because of the regularity with which the sun, the moon and the planets move.

__ Metaphors __ Understanding that there are regular rules that by repeated observations allow us to predict future events is not complicated. The essence of science is simple. However, there is another aspect to science that helps us to make predictions but can also complicate it. When we discover a rule we try to explain it in terms of something we already understand – we explain it in terms of a metaphor. An example of a metaphor used to explain a quantitative prediction is that by the twelfth century scholar Ibn Khallikan to explain **__exponential growth__**. Two kings were playing chess. The winner commanded a prize from the loser. The wining king asked to be paid by placing one grain of wheat on the first square of the chess board, two grains on the second one, four on the third, and so on. The grains were to double each time until all 64 square of the chess board were filled. Thinking he was getting off easy the losing king agreed to pay up. To his surprise the number of grains was more than all the wheat that the king had ever harvested from his kingdom. This fictional story illustrates the scientific rule of exponential growth. In this story the king would have to pay up (2^64) - 1 or, in words, two the sixty fourth power minus one that's 18,446,744,073,709,551,615 grains of wheat - a quantity far greater than a thousand years of U.S. wheat production. ( from <[]> ) Another example of a metaphor used is in science is that of planetary motion. For planetary motion, the idea that planets moved in circles around the sun did a pretty good job. However, careful measurements showed that this metaphor was not accurate. It became more accurate when we substituted ellipses for circles. It became even more accurate when we included the pull of gravity by planets on one another. And it became even more accurate when we included the fact that the sun and planets distort space. All of these images are metaphors. They get better with time but are never the whole story. The important part is the measurement that allows us to predict the future. The metaphor can help us to think visually but they can be complicating because they are never completely right. And sometimes there is no adequate metaphor from everyday experience - such as the bending of space by mass. So when we need to understand the science behind important natural processes, if we will stick to the rules and predictions. It will make it easier.

__ Population __ You will learn in this course that one of the most important influences working against sustainability is the increase in the size of the human population. The human population has exploded in the last few generations to a size that has reached the limits of what the planet’s resources can support. In fact, it has been estimated that if all human beings lived as affluently as we do in the US it would take more than 4 earth planets to support us.

If we could control our population we could solve the sustainability problem. How many earths do you take up? Visit this website to take a simple quiz and find out [| http://www.myfootprint.org/]. Wackernagel and Rees in 1992 at University of British Columbia in Vancouver, Canada came up with a method for calculating this question, the ecological footprint.

The "**__Ecological footprint__** analysis compares human demand on nature with the biosphere's ability to regenerate resources and provide services. It does this by assessing the biologically productive land and marine area required to produce the resources a population consumes and absorb the corresponding waste, using prevailing technology. Footprint values at the end of a survey are categorized for Carbon, Food, Housing, and Goods and Services as well as the total footprint number of Earths needed to sustain the world's population at that level of consumption." ( from <[]>)

Therefore our understanding of the science of how the population grow s, our ability to predict how much it will grow and our technology for controlling human reproduction are critical for sustainability. We have learned a lot about reproduction in the last few decades.

Since each mother and father will die, the population will remain constant if they produce exactly 2 children (actually it is 2.1 in a healthy society due to child mortality and more if there is a lot of child mortality); it will increase if they produce more and it will decrease if they produce less. We determine the rate of population growth by the straightforward process of sending people out to count the population – taking a census. The first important principle of reproduction is that populations can grow exponentially. If the average couple produces more than two children then there are more people each generation. If those people continue reproducing at a rate greater than two children per couple then the rate of increase grows as well. This is just like putting your money in the bank and getting interest. If you leave the interest in your account the principle gets bigger and the rate of growth gets bigger. Over many generations, exponential growth can produce surprising large increases. For most of the 20th century the growth rate was far above 2.1 for nearly all countries. Now, however, it is less than 2.1 in many countries – and here is the big surprise. It is lowest in the most affluent countries. The 230 countries analyzed include several territories and colonies under the title of 'country'. The data is from the 2006 edition of the World Population Prospects report.



In the very countries where people can afford lots of children they choose not to have very many. That is a behavior contrary to all other species – when conditions are good all other organisms produce more offspring.

The contrariness of humans is one of the most hopeful facts for sustainability. As the world increases its affluence, which it is doing continuously, it decreases its reproductive rate. Most economically developed countries have a negative or very low population growth rate – that is, the number of children produced is less than that needed to maintain the population. Italy, Japan, Spain fall into this category. This is a good outcome for sustainability. However, many other countries like Niger and Somalia are continuing positive population growth, and the overall outcome for the world is still continued population growth at a rate of 1.17%

Population statistics can show be shown visually with age structure diagrams. Basically these diagrams are pyramids. Let's look at the case of Japan. Normally, in expanding countries like Japan was in 1950, the age structure diagram is shaped like a pyramid. In this pyramid, many young people are at the bottom with fewer and fewer people with age at the top of the pyramid. However, with present reproductive controls Japan's pyramid has morphed into another shape from 1950-2007. Currently, Japan's birth rate is 1.34 below the needed rate to maintain the country's population. Projections show that with the increasing number of people using various forms of reproductive controls the age structure diagram will be inverted by 2050 in Japan. Ultimately, there will be more people at the top and less young people at the bottom. ( from [] and []) This adjustment to a negative growth rate will produce difficulties in the short term because people are also living longer and it means that a decreasing number of young people will have an increasing number of old people to care for. The main reason this is happening is because science has learned enough about the rules of reproduction that we can now, for the first time in our history, control our reproduction.

(from image from CNN)

We have a choice that we have never had before. Estimates that account for all countries and their reproductive changes project that the world population will level off at about 9 - 10B people about 2050. That is still half again as many people as today and its going to be difficult to provide for all of them.

__ The science of reproduction __ One of the most important sciences for sustainability is biology and especially the science of reproduction. Our understanding of it allows us to predict population increases and even to control population growth. We can also use our understanding of biological reproduction to produce organisms with novel capabilities such as pest resistant crops that can increase food production.

The science of reproduction can seem very complicated if we explore all the details, but if we stick to the rules its quite simple. The rule is 2. An Austrian monk, name Gregor Mendel, discovered in the 1860s that pea plants had two entities, that we now call genes, for each trait or characteristic. Pea plants could differ in being tall or short, having wrinkled or nonwrinkled pods, green or yellow cotyledons, etc. Mendel studied seven common differences and they all behaved the same. By breeding different types together and counting their offspring and their offspring’s offspring he deduced that each plant had two genes for each of these traits and that each parent contributed one of their two, at random, to its offspring - Simple. This rule has turned out to be true of all plants and animals. Some human characteristics and diseases follow the simple rules deduced by Mendel – for example, sickle cell disease. These rules were reflected in the behavior of our reproductive cells, the behavior of their organelles, the chromosomes, and in the behavior of their chemistry, the DNA molecule. Everything goes by twos. Two types of each chromosome with only one of the two contributed by each parent to the offspring. Two complementary strands of DNA that separate to form templates for the reproduction of DNA at each cell division. The discovery of the cellular basis of reproduction led to an understanding of how hormones control egg reproduction in females and this has led to our ability to control female fertility. The “pill” has been a major factor in allowing women to delay child bearing and in the reduction in family size. The discovery of DNA as the hereditary molecule has led to a whole industry using recombinant DNA technology that can manipulate and change resulting in crops with new characteristics, organisms that can produce useful pharmaceuticals and promising in the relatively near future the correction of genetic disease and the engineering of organisms with novel traits for human use.

The problems to be faced are vast and complex, but come down to this: 6.2 billion people are breeding exponentially. The process of fulfilling their wants and needs is stripping earth of its biotic capacity to produce life; a climatic burst of consumption by a single species is overwhelming the skies, earth, waters and fauna. -- Paul Hawken ([|http://www.paulhawken.com])