Have you ever stopped to consider how your lifestyle is affecting the global ecosystem? If not, maybe it's time to have a look at your ecological footprint.

If it was share-and-share-alike with the Earth’s resources, you could work out exactly what your own share is. If you look specifically at biological capacity you get 4.4 acres (1.8 hectares) of land each — about 20 housing plots. In other words, if we’re not to deplete the Earth’s resources nobody should claim more than 1.8 hectares. This is what we call our “ecological footprint.” On www.myfootprint.org you can do a simple test and get your answer in black and white.

As you might expect, the ecological footprint varies greatly depending on where on the planet you live, whether you live in the country or in a city, whether you drive a car, how much electricity you use, what kinds of food you buy, and so on. Most decisive is how much fossil fuel you use.

The average Swede has a footprint of 14.8 acres (6 hectares), while the United States and the United Arab Emirates have 24.7 acres and 29.7 acres (10 hectares and 12 hectares) per person respectively. Samoans and Afghanis have a tiny footprint of less than half a hectare (1.3 acres) each.

It’s worth reflecting on other aspects of our modern life style too. Urbanization, for example. Carl Folke, Professor of Natural Resource Management at Stockholm University, claims that there are enormous ecological challenges in a world where more and more people are city dwellers.

“We’re living on a planet that’s been shaped by humans for as long as we’ve been around," he says. "The difference today is that the changes are happening faster and on an unprecedented scale. In 1960 about 34 percent of the Earth’s population lived in cities. Today it’s around 50 percent, and the UN calculates that the figure will be 60 percent by 2025. The world’s cities are growing by a million people a week.”

In what way do urban people affect the Earth’s resources?

“Urban areas constitute only a small part of the Earth’s surface but they release 80 percent of greenhouse gases," Folke says. "And something happens to people when they move to a city: they often distance themselves from their natural surroundings.

"The environment becomes a sector instead of a part of everyday life. People become illiterate about their dependence on ecological systems. Merely living in a city doesn’t make you independent of nature, even if we sometimes live and think as if it did.”

Folke took part in an analysis of 30 big cities in the Baltic region, studying their relationship to and dependence on surrounding natural systems.

“We found that the cities needed areas about 200 times larger than themselves to produce timber and food for their needs," he says. "If you do similar calculations for carbon dioxide and nutrient emissions, the surface area needed becomes a thousand times larger than the city itself.”

What can we do about all this? According to Folke, it depends on your view of the world:

“How we look on nature is going to be more and more important. We’re talking about value judgments and behaviors that are rooted in our view of the world. We must understand that we’re a part of nature. We can’t set ourselves above it and pretend that we’re independent of the biosphere.”

Damaged body organs replaced with new, healthy ones grown from the patient’s own stem cells? Can this be the health care of the future — cultivating new organs in laboratories? What are the limits to the possibilities of stem-cell research?

One man in six will develop prostate cancer. Imagine using stem cell technology to give these men new prostate glands. An Australian research team recently reported that they had succeeded in producing prostate tissue outside the human body. They were able to get human stem cells to produce exactly the right type of cell. The manufactured tissue behaved just like a healthy prostate should — as they saw when they implanted it into mice. The next step is to test the tissue in humans.

This research area is called therapeutic cloning, producing new body organs from the patient’s own cells.

To clone means to copy. Pinching off a leaf from a pot plant is cloning — if the leaf is put in earth, roots will grow and you get a new plant with exactly the same genetic code as the old one.

Therapeutic cloning starts with a woman’s unfertilised egg cell. Instead of fertilising it in the normal way the researcher replaces its contents with the contents of a complete cell from the patient to be treated. The manipulated egg now behaves like a normally fertilised egg. It starts dividing and soon you have a set of stem cells which theoretically can be developed into any kind of cell whatever.

Professor Johan Ericson is a stem cell researcher at Karolinska Institutet in Sweden. Though not involved specifically in this kind of application he reflects generally on stem cell research in the future.

“Our knowledge of early embryo development is growing fast just now," he says. "We’ve learned to control stem cells so that they specialize as we want them to. But getting exactly the right kind of cell has been harder than we thought.”

Too hard perhaps? Is your research really as promising as it seems?

“Stem cell biology is a young research field and there have been a lot of trial-and-error approaches," Ericson says. "That’s why we got so much attention when our method worked. Now we can make the type of brain cell that produces dopamine, so we’re a step nearer a treatment for Parkinson’s disease. Diabetes is another disease where stem cell research looks promising.”

How does Professor Ericson see the future? Will we be replacing sick cells or damaged organs with healthy ones?

“Rejection mechanisms are always a problem," he says. "And this is where therapeutic cloning comes in. You use the patient’s own cells and you grow compatible cells. But we must be careful not to promise too much. Many patients light up with hope when they hear about the possibilities of stem cell research. But therapeutic cloning is still a very difficult and expensive method.”

Scientists have a new box of toys. With new "spectacles" and precision instruments they can not only see into the smallest of things but can also alter what they see. They can build molecules that didn’t exist before, change ones that need improving. What does design at molecular level — nanotechnology — actually imply?

Where do you start if you want to enter Nanoworld? The Ångström Laboratory in the university city of Uppsala, of course. Anders Ångström (1817-74) was a physicist working in Uppsala a hundred years after Linnaeus. He introduced the unit of measurement later named after him. One Ångström is 0.0000000001 meters long, the tiny distance you get if you divide a millimeter into ten million equal parts.

Today physicists all over the world use the Ångström unit, even though an international convention has ruled that equal thousandths of a meter should be used instead. In this nomenclature one-thousandth of a meter is called one millimeter (1 mm). Another thousand times smaller is called one micrometer (1 μm) and a thousandth of a micrometer is a nanometer (1 nm). So, 1 nanometer is the same as 10 Ångström — the same relationship as that between a millimeter and a centimeter. Enough maths for one day!

The nanometer has given its name to a whole new branch of science, nanoscience. But how small is small, actually? What is there that’s so small? Professor Maria Strømme, a nano scientist at the Ångström Laboratory in Uppsala, explains:

”Many molecules are around 1-10 nm in size. A water molecule is even smaller, it’s only a few Ångströms. The proteins in our cells are about a thousand times bigger, around 100 nm.”

Do we need new molecules — aren’t there enough as it is?

“It’s not until you can study a molecule in detail — and I’m talking about nano level here — that can you understand how it works," Strømme says. "And when we understand how it works and how it cooperates and reacts with other molecules, then we can imitate precisely the functionality we’re aiming to achieve.

"Take pharmaceuticals as an example. They often act by one molecule finding a special place in a cell where they interact in a certain way to prevent disease — just like a key in a keyhole. So the trick is to build exactly the right key molecules.”

So what is the smallest thing we can build? Strømme has a very clear picture:

“Strange things start to happen to matter when we come close to individual atoms," she says. "This is because of what’s known as quantum effects. Common sense no longer applies here. A particle can be in two places at once, a current can flow in both directions at the same time — things like that.

"My guess is that we’re getting closer and closer to an exciting limit when we build molecules and structures that are a few Ångström in size. But we’ve some way to go before we reach that limit. Right now we can precision-build structures that are ten times bigger than that, a few nanometers.”

Joy, grief, gnawing anxiety… We have a rich spectrum of emotions which we often see as opposites to our ability to be rational. Why has evolution provided us with these apparently irrational "disturbances"? What’s the point of feelings?

We can all remember times when emotions such as grief or anger have paralyzed us — when they’ve got in the way of normal life. At other times we experience emotions that enrich our lives to the extent that we can’t imagine existence without them. In the course of evolution, mankind has developed a rich emotional life. With a single subtle change in facial expression we signal that one emotion has been replaced by another. 

Why has this been so important for us? Apart from the obvious social implications, scientists are now getting interested in the significance of emotions for the brain’s development and for learning itself. There seems to be no conflicting relationship between reason and emotion — rather the reverse.

Professor Peter Gärdenfors at Lund University is what may be called a biologically oriented researcher into consciousness. He explains:

“People may think that reason and emotion are opposites — that emotions upset the rationality of an argument. But it’s rather the other way round: they support and reinforce rational reasoning. Without emotions we find it difficult to evaluate our actions and their consequences. The types of brain damage that lead to the disappearance of certain emotions also mean that the patient finds it harder to make rational decisions — mainly in social contexts.” 

How do our emotions connect to the development of speech and self-awareness?

“Emotions facilitate learning," Gärdenfors says. "Emotionally charged material is easier to learn than neutral material.”

So emotions work as an inner compass guiding us to the best decisions. They also serve as short cuts to our memory. How are these functions linked to human evolution?

“As our ancestors got better and better at planning for future needs, so it became more important to have a system to help them avoid egoistic short-term gain," Gärdenfors says. "If we experience satisfaction when we save food and fuel instead of using it up all at once then we have a better chance of surviving the winter.” 

What Professor Gärdenfors finds uniquely human is the fact that the development of our emotional lives has been accompanied by the evolvement of self-awareness — our ability to reflect on our emotions. As far as we know, we are the only creatures to do so.

“When a little child feels shy it’s a sign that he or she realizes that other people are looking and listening," Gärdenfors says. "The child is aware of himself or herself in relation to us, the others. This normally occurs at the age of around nine months in human children, but I have yet to see a single animal show shyness, not even young chimpanzees. They see me but they don’t realize that I see them!”

Asked “what is a human being?” a biologist will answer “99 percent ape and 1 percent unknown.” Only one single percent of our genetic material differentiates us from our nearest relative in the animal world, the chimpanzee. The latest research shows that this vital little one percent has to do with the brain…

All biology is history and in history’s rear view mirror we see the results of our extinct relatives’ successful attempts to breed. You yourself are the product of an unbroken line of development. If you go far back enough you’ll get to a pair of chimps in Africa. You share 99 percent of your genetic material with mankind’s closest relative, the chimpanzee. And yet we and the chimps live totally different lives. Even biologists are puzzled that the difference in genes isn’t greater.

Hans Ellegren is Professor of Evolutionary Biology at Uppsala University. His aim is to combine knowledge of the small things that happen at cell level (molecular biology) with knowledge of the large biological systems and their development (ecology and evolutionary biology) to give us the really big picture that will answer many questions, including what distinguishes human beings from other animals.

How, then, does Ellegren answer the question of what’s so special about us humans?

“Only one percent of our genes differ from those of the chimpanzee, so that’s hardly a satisfactory answer,” he says. “However, we’ve recently begun to get an idea of what that important one percent contains. We also understand now that it’s not only differences in how genes are designed that matter, it also depends on when and where and to what extent genes are turned into proteins.

"Apparently, humans make proteins in the brain in a different way from chimpanzees. So it’s differences in brain function that will tell us what’s uniquely human.

“One gene that’s particularly interesting is called ASPM, and has to do with brain growth and size. In other mammals there are relatively few changes in this gene, but in the lineage leading to man there’s been a substantially higher speed of evolution in which mutation after mutation has successively altered the protein.”

Another gene that’s attracting scientific attention is MYH16, which controls the formation of an important muscle in the jaw. An alteration in this gene about two million years ago reduced the size of this muscle. At the same time the lower jaw changed shape from jutting out (as in most apes) to flatter (as in man).

And lastly, the gene that is perhaps attracting most interest is FOXP2, the "speech gene."

“People in whom this gene is damaged have severe speech defects," Ellegren says. "About 200,000 years ago this gene went through two mutations. It’s obviously tempting to speculate that this gene alteration gave man the ability to speak, but it presumably took more than just two alterations. It’s also unlikely that speech resides in one single gene.”

Rapid advances are being made in this hot research field. It’s now well established that what separates us from the apes has to do with our well-developed brain. Perhaps we should pass on the question to someone who researches into our inner world, our thoughts and consciousness.

An incredibly small electronic switch, a nano relay, has been built in Gothenburg, Sweden. It’s a million times thinner than an ordinary switch. But how can we use this new technology when we have no chance to see what’s happening?

Carbon nanotubes are the cables in the Nanoworld Hall of Technology. They consist of quite ordinary carbon atoms, like those in the graphite of your “lead” pencil, but arranged to form long hollow tubes. They are extremely thin, only a millionth of a millimeter across, but they can be made several centimeters long.

Professor Eleanor Campbell and her research team at University of Gothenburg have built a nano relay, and other tiny nano components are on the way. Molecular electronics is now a reality.

“Things are developing fast and it really feels as if we’re producing an entirely new experimental kit of nano-scale components," Campbell says. "In theory, carbon nanotubes can play the same role as silicon does in electronic circuits at present, but on a molecular scale where today’s silicon and other semiconductors stop working.”

So what is a nano relay — and how is it possible to build anything so tiny?

“A relay is an electrical switch that you turn on and off by sending it a voltage pulse," Campbell says. "It’s a sort of remote-controlled switch. There are masses of them in all electrical circuits. Our nano relay in fact consists of a single carbon nanotube which is 200 nanometers long and only 10 nanometers in diameter.

"When we put a voltage on an electrode underneath the nanotube it bends so that it makes contact with another electrode and conducts current. As soon as the voltage is turned off the current is cut. This happens extremely fast and the relay uses almost no energy since it’s so small and light.”

Carbon nanotubes can also be used in batteries, in displays and as an entirely different kind of lighting.

By varying the conditions when growing the nanotubes, Campbell and her colleagues can produce threads with a variety of characteristics. They can also produce dense "forests" of multiwalled nanotubes and other entirely new materials. At present the team’s working on a tiny and very special molecular machine.

“We call it a pea shooter," Campbell says. "We want to shoot out molecules one by one from a nanotube, like peas from a pea shooter. It’ll be fascinating to watch the molecules popping out!”

And what do you think you can use it for?

Campbell laughs:

“That’s something we haven’t quite worked out yet!”

In the movies, smart robots at our beck and call are a commonplace. So why is it taking so long to get there in reality? When will it be just as natural to have a pet robot as to have a pet animal? And what can we learn about biological life when we design artificial life?

Pablo Picasso is said to have remarked “Computers are useless. They can only give answers.” Perhaps it’s as simple as that. Computers, machines, robots — they’re only products of human hands. They’re quick at calculating and efficient at remembering. But it’s still we humans who call the shots.

Professor Peter Gärdenfors is a philosopher. He’s interested in both the human mind and artificial intelligence:

“If we managed to build a really good robot it would be an interesting test problem for us," he says. "A thinking robot needs memory, perception, knowledge, the ability to learn, the capacity to communicate and some kind of ability to plan ahead — things we humans deal with every day.” 

So what’s the hardest problem to solve? Why aren’t we there already?

“The industrial robots we have aren’t very independent, nor are they flexible," Gärdenfors says. "They do precisely what they’ve been programmed to do and nothing else. Thinking robots would be more like us, and they’ve proved to be enormously hard to construct. We’re humbled by nature, where evolution has been working for millions of years. We simply don’t understand the whole evolutionary picture.”

Understanding what a robot must learn touches upon the very concept of "understanding," according to Gärdenfors:

“We’ve been developing computers for decades now but we can’t yet use them to understand things — machines are bad at that," he says. "On the other hand, they can visualize and they can be used to simulate phenomena. Computers have become true tools, in teaching for example.”

So getting computers to understand, to learn on their own, has proved to be much more difficult than we thought.

“And remember that human beings and animals are motivated to learn," Gärdenfors says. "Evolution has provided us with subconscious structures, complicated reward systems in the brain that cause us to choose one action rather than another. Robots don’t have motivation.

“Another important thing is the ability to plan. This is where humans are unique in the animal world. If we want to teach a machine to see the consequences of its actions it must first have some model of the world around it.” 

So building a thinking robot is more complicated than we first thought. Perhaps it ought to build itself instead, if it’s to resemble us in intelligence? This naturally raises a host of ethical problems.

How do we feel about the prospect of being surrounded by independent, thinking machines? How far has the research come?

“It actually seems most logical to get robots to imitate our own development, for example learning through play," Gärdenfors says. "We’ve made some progress by getting infantoids — "child robots" — to interact with real children.”

But he points out that research is in its infancy and there’s a lot to be done before robots possess both self-consciousness and emotions.

“Heaven preserve us from psychopathic robots!”

Jumpers that never smell of sweat, windows that never get dirty, transparent concrete, carpets that change color and act as indoor air cleaners, scratchproof car paint — with nanotechnology we’ll soon be able to manufacture the most spectacular materials. But what materials are we actually going to need in the years to come?

The boys in Mio, My Son, the children's book by Swedish author Astrid Lindgren, wrap themselves in cloaks woven to be invisible when turned inside out. Harry Potter does the same in later literature.

Nano scientists are perhaps the fairy-tale-tellers of our time — or can matter really assume any properties we want?

Professor Maria Strømme at Uppsala University is among Sweden’s most successful nano scientists and she’s not telling fairy stories. Many of her discoveries and materials are already being processed in laboratories the world over. But you still can’t help being amazed at what she has to tell…

“Energy-saving materials for the building industry are going to come on strongly, and ways of producing energy, batteries and other things we’ve not ever dreamed of," she says. "Then there are medical drugs and simple diagnostic methods, of course.”

No cloaks of invisibility, then? Strømme laughs:

“It’d be great to have one sometimes. I heard that a research team had managed to produce a material that refracts light so you can’t actually see the material itself. That’s not exactly what we’re working on here, I’m afraid.”

Strømme and her colleagues are involved in many projects. One she finds extra interesting is the puzzle of how the transport of charge inside molecules works. This is pure basic research on a fundamental problem that she and other nano scientists absolutely must get to grips with. If they’re to be able to produce the materials of the future — and do it in entirely new ways — understanding electrical conductance is an important milestone.

“We’re developing tiny nano electrodes which we’ll be able to use to measure how molecules that are only 3–4 nanometers long conduct current," Strømme says. "A nanometer is one-millionth of a millimeter, so this is really Lilliput-physics.”

Molecular electronics is one link in eventually developing a whole new molecular toolbox for controlling how molecules can conduct electrical charges.

“Nanotechnology in the future won’t be top-down as it is at present — meaning that you build material layer-by-layer like in silicon chips," Strømme says. "Instead, the material will be able to build itself up just as we want, if only we can provide the exact conditions and control the whole process in detail.”

So Strømme has a kind of bottom-up vision of the future of nanotechnology. And the absolutely most promising discoveries and innovations, she believes, will come in the borderlands between the more established sciences, between molecular biology, nanotechnology, genetics, atomic physics, mathematics, neurology…

What did the late Pope John Paul II have in common with former world boxing champion Mohammed Ali and actor Michael J. Fox? Answer: Parkinson’s disease. New stem cell research is giving the sufferers hope — but when will they get a treatment that works?

Parkinson’s is a ruthless nerve disease. The sufferer grows stiff, has difficulty in moving, trembles when resting, fumbles. Many also become depressed. We don’t know what causes the disease. The available drugs often have serious side-effects, and they don’t help all the way.

Many medical researchers have regarded curing Parkinson’s disease as an impossible dream. But Swedish researchers have recently made an important breakthrough. Professor Johan Ericson at Karolinska Institutet is one of them.

“I realize that anyone reading this who has the disease, or who knows someone with it, is impatient," Ericson says. "It’ll be an enormous day for all of them, as well as for us scientists, when we can at last see people getting better.”

He sounds optimistic. And he has good reason. A few years ago Ericson and his colleague Thomas Perlmann managed to find the starter button, the genes that initiate and control the brain’s dopamine-producing nerve cells. In Parkinson’s disease these nerve cells stop working and the brain runs short of dopamine. This has a particularly devastating effect on the control of muscle movement.

“We can now get embryonic stem cells to develop into nerve cells," Ericson says. "We can also make sure that exactly the right types are formed. There are a thousand or so kinds of nerve cell so it takes a bit of doing to get dopamine-producing cells of just the right kind. But we’ve managed it.”

So far, the research has been carried out on chicken and mice, but Ericson is convinced that it will also work on us.

“A look back at the history of evolution shows that we share these genes with other animals — mice and men are incredibly similar in this respect," he says. "So the next step is to transplant these new cells into sick mice.”

Have you seen any results yet?

“It may sound as if we could start transplanting humans right now, but we still have some tough problems to solve," Ericson says. "One thing is that we haven’t yet succeeded in producing entirely pure samples of the dopamine-producing cells. We’re still getting 10%−20% of other ‘rubbish’ stem cells as well. We have to find a way of getting rid of these.”

When can we expect the first clinical trials with humans?

“I think it’ll be within the next ten years.”

Some of the support for the research that Ericson and his colleagues are carrying out in Sweden comes from the Michael J. Fox Foundation in the United States. Money itself cannot cure the disease. But the scientists need money to make progress — something Michael J Fox has realized.