地缘贸易博客This blog considers how ideas and events framed by geography and trade shape our world, while sharing observations and analysis on discovery, transport, industry and much more.






Saturday 30 June 2012

Life in the Universe - why do living things die?


Living things glow in the dark

Is there life outside Earth?

By far the strongest driving force for the exploration of the Mars is the question: Is it alive? From thousands of images and measurements we have already ruled out the presence of large surface plants and animals. What we cannot entirely dismiss, however, is the possibility of “invisible” Martians such as micro-organisms or anything that could exist below the surface. What makes this question so important is that from a “Yes” we can infer that life is probably prevalent throughout the universe. And there is nothing that an astrobiologist would love more than to be able to analyse the sequence of alien DNA (or other genetic code) to compare with terrestrial organisms.

Given the hostile Martian surface environment, if we are going to detect  traces of life, we will need highly sensitive instruments that look for the faintest possible biological signatures such as organic molecules. This is where the story begins to sound more like something out of science fiction. In order for an astronaut to step down onto the surface, they will need to step out of an airlock from their spaceship. By necessity, the volume of this airlock will first be exposed to the inside of the spacecraft, and then to the Martian atmosphere. Even clever designs like the lunar electric rover suitport suffer from this inherent limitation. Living on the surface of each astronaut will be one trillion microorganisms, representing more than 1,000 species of skin flora. Combined with microorganisms from other parts of the body, every single astronaut will bring along to Mars a soup of Earth micro-organisms that will be released into the atmosphere every time they climb out of the hatch. These micro-organisms can, under favorable conditions, multiply every 20 minutes, allowing them to rapidly grow, mutate, and adapt to adverse environmental conditions. 

One of the adversities on Mars is the high level of UV radiation, which will kill off many of the bacteria that remain exposed on the surface. The organic remnants from these bacteria and viruses could potentially fool ultra-sensitive instruments. Some bacteria will become shielded from the UV, buried just below the surface by footsteps and wheels. And for some, such as a strain that has come to be known as Conan the Bacterium, radiation is not a problem. Through an elaborate collection of repair mechanisms, it is capable of withstanding radiation more than 1,000 times greater than any other known living organism. And beyond that, there is the concern of reverse contamination. With each return of an astronaut to the ship, the airlock would introduce Martian biological remnants to the crew, and subsequently, to Earth. We don’t know how serious this might be, but, historically, human exploration has frequently resulted in epidemics.

Why do living things die?

Every single-celled organism alive today has been in existence since life began over 3 billion years ago. This is because individual cells do not give birth, they divide. After cell division, the two cells that result are each as old as the single cell that preceded them. The cell does not become younger by dividing. Hence every cell in your body is over 3 billion years old.

The strategy that multicellular organisms such as humans use to project themselves into the future is to create new cell colonies from a single undifferentiated cell rather than maintaining existing colonies indefinitely. The main reason is that reproduction is more flexible and robust than maintenance, and it provides a way of starting over with a "clean slate" and slightly different genes. Complex organisms accumulate billions of errors and problems over their lifetime. Most of these errors are fixed as fast as they happen, but life takes a toll and not all problems are reversible. Just as reinstalling Microsoft Windows every so often fixes accumulated system issues, so does generating a new organism every so often from a single cell.

Given that biology has selected this strategy, evolution has optimized for producing the most successful offspring. Once the individual has reproduced, its only evolutionary role is to support the success of its offspring. Aging longer is just not something evolution has had a reason to optimize. And in fact given limited environmental resources, the offspring often do better if the older generation doesn't stay around forever competing with younger generations for scarce resources.

In terms of what happens physiologically, there are two main contributors to aging. The first is the accumulation of biological defects. Viruses and disease take a toll even after healing; UV rays slowly but inevitably damage DNA; and proteins, cell structure, and the neurons which hold memories all degrade over time due to thermodynamic molecular disruptions and invasions by other species.

The second is the aging process itself. The organism develops to maturity and ages in stages according to a genetically determined life plan. Muscles atrophy, bones brittle, and metabolism changes. But the life plan has never run more than 80 years until recently, and evolution only ever optimized the first 40 years or so. So humans are in new territory that is poorly understood, and which evolution has never had a reason to fine tune.

It may be possible to slow or stop some of the genetically determined aging processes. While this may not be good for an overpopulated planet, it will be popular with ageing populations in many developed countries.

Saturday 16 June 2012

The inner workings of the brain and mind


Real time brain scanning technology

The idea of the unconscious, a second level of the mind that is inaccessible to rational thought, but which nevertheless influences people’s behaviour was drawn from Freud's idea of psychoanalysis. During the 20th century, the idea of the unconscious lost its appeal due to the rise of more scientific approaches to psychology. These focused purely on studying behaviour and refrained from theorising about the inner workings of the brain and mind.

A new book on the "unconscious"
 
In a new book entitled “Subliminal”, its author, Leonard Mlodinow shows how the idea of the unconscious has become fashionable again in the 21st century. It has been helped by rigorous experimental evidence of the effects of the subconscious and, especially, by real-time brain-scanning technology that allows researchers to examine what is going on in their subjects’ heads.

This experimental evidence suggests that, as Freud suspected, conscious reasoning makes up a comparatively small part of the activity in the human brains, with most of the work taking place where we are not able to tap into it. However, unlike Freud’s unconscious, the modern unconscious is a place of super-fast data processing, useful survival mechanisms and rules of thumb about the world that have been honed by millions of years of evolution.

It is the unconscious, for instance, that pulls together data on colour, shape, movement and perspective to create the sight enjoyed by the conscious part of the mind. Experiments on people with certain specific forms of brain damage, which remove the ability to perform some of these tasks, can reveal something about what is going on in the unconscious. People with “blindsight” can respond to some visual stimuli even when they are not conscious of being able to see. For example, asked to walk down an obstacle-strewn corridor, they will dodge and weave and arrive at their destination unharmed because some residual data is still making its way into their brains, although at a level that is beneath the notice of their conscious minds.

The modern view of the unconscious mind may be more benign than Freud’s, but it can still generate unwelcome impulses. Psychologists theorise that the well-documented tendency of humans to categorise almost every piece of information they come across is a survival mechanism that evolved to aid quick decision making. Yet it may also lie behind the tendency for human beings to group people into races, genders, creeds and the like, and then to apply certain characteristics, often unjustifiably, to every member of that group.

The insights offered by modern science into the workings of the human mind are fascinating in their own right. But they also suggest that plenty of conventional wisdom about how humans behave may need rethinking. In his new book, Mlodinow notes that economic models, for instance, are built on the assumption that people make decisions by consciously weighing the relevant factors, whereas the psychological research suggests that, most of the time, they do no such thing. Instead, they act on the basis of simple, unconscious rules that can sometimes produce completely irrational results. 

Consciousness and Self

Consciousness is the core of an individual's sense of self, yet, paradoxically, it is the most elusive concept in biology. One feature of human consciousness that students of the field suggest might be unique is an awareness of self. The idea that self-awareness might be specific to humans and a few close relatives resulted from an experiment done three decades ago by Gordon Gallup, who now works at the University of Albany in New York state. This showed that chimpanzees (and, as subsequently emerged, other great apes) share with humans the ability to recognise themselves in a mirror, whereas monkeys and various other reasonably intelligent species, such as dogs, do not. A few species that are not apes have also passed the mirror test, including elephants and dolphins. But most animals fail it. All the species that have passed have something in common: abnormally large cerebral cortices relative to the rest of their brains. Whether selfawareness simply emerges from a large cortex or whether selection for it necessarily results in one is unclear. 

What is consciously perceived is not a simple mapping of the images that fall on the retina. Instead, the signals from the optic nerves are deconstructed and re-formed in a process so demanding that it involves about a third of the cerebral cortex. An even more obvious discord between reality and perception is colour. The world is not really coloured, it just looks that way because it is tremendously useful that it should, so the retina has cells that are particularly sensitive to three different wavelengths of light, and the brain weaves the signals from them together to create the phenomenon called colour.

For some time we have believed that conscious free-willed thought could override unconscious desires. But one way of interpreting the inner workings of the brain and mind is that it is possible, that such free will is, like colour vision, simply a powerful illusion. But the truth, unsatisfactory though it is, is that no one really knows. But one thing we can be sure of is that neuroscience is one area where big concepts almost certainly remain to be discovered. And when they are, they are likely to upend humanity's understanding of itself.
 
 




 

Thursday 7 June 2012

The Future of the Nation State in the 21st Century

Flag Map of the World




The idea of the territorial state’s sovereignty goes back to 1555, when at a meeting in Augsburg called by the warring dynastic rulers desperately seeking an exit or at least a respite from the devastating religious wars tearing the Christian Europe apart coined the formula cuius regio, eius religio (he who rules, determines religion of the ruled). 
 
Sovereignty meant supreme – unconstrained by external interference and indivisible – authority within a territory: Since its inclusion into the political vocabulary the concept of sovereignty referred to a territorially confined state of affairs and territorially fixed entitlements. 
 
Any attempt to meddle with the order of things established by the sovereign on the territory of his rule was therefore illegal, condemnable, a casus belli; the Augsburg formula may be read as much as the founding act of the modern phenomenon of state sovereignty as well as it is read, simultaneously and necessarily, as the textual source of the modern concept of state borders.

It then took almost 100 years more until 1648 when the “Westphalian Sovereignty” agreement was negotiated and signed in Osnabrück and Münster, this allowed the principle recommended by the Augsburg formula to take hold of European social and political reality: a full sovereignty of every ruler on the territory they ruled and over its residents – that is, the ruler’s entitlement to impose “positive” laws of their choice that may override the choices made individually by the subjects, including the choice of God they ought to believe in and must worship.

By a simple expedient of substituting “natio” for “religio”, the mental frame was used to create and operate the (secular) political order of the emergent modern Europe: the pattern of nation-state – that is, of a nation using the state’s sovereignty to set apart “us” from “them” and reserving for itself the monopolistic, inalienable and indivisible right to design the order binding for the country as a whole, and of a state claiming its right to the subjects’ discipline through invoking the commonality of national history, destiny and well-being.

The Westphalian Model in the 21st Century

After the two world wars in the 20th century the Westphalian model of sovereignty was once again the basis on which the Charter of the United Nations was founded - an assembly for the rulers of sovereign states called to collectively monitor, supervise and defend the state of peaceful coexistence. In fact, Article 2(4) of the Charter prohibits attacks on “political independence and territorial integrity”, whereas the article 2(7) sharply restricts the eventuality of an intervention from outside into affairs of a sovereign state. 
 
So far the United Nations is still the closest we have to an idea of a “global political body”. But it clearly has the entrenchment and defence of the Westphalian principle written into its charter.  While many powers (finances, commercial interests, information, drug and weapon trade, criminality and terrorism) have already obtained in practice the freedom to operate on a global level. The absence of global political agencies capable of catching up with the already global reach is held back by the grip of the nation-state and the rhetoric of state sovereignty. We live still in a “post-Westphalian era”. The process of emancipation from the shadows cast by “Westphalian sovereignty” is increasingly protracted.
 
A recent example of this is the fate of euro: the absurdity of a common currency served by seventeen finance ministers, each bound to represent and defend their country’s sovereign rights. The plight of the euro highlights the limits of local (nation-state) politics under pressures coming from two distinct, uncoordinated and thereby not easily reconcilable authoritative centres, the nationally confined electorate and supra-national European institutions, all too often instructed to act at cross-purposes. This is just one of many manifestations of a double bind: the condition of being clenched between the ghost of the Westphalian state sovereignty on one side and the realities of the global, or regional nonetheless supra-national, dependency on the other.

The essential problem of nation-state sovereignty in a global world

During the 17th, 18th and possibly 19th centuries, the nation-state was relatively well attuned to the realities of the time, but the Geo-Trade blog believes this is no longer the case. In the 21st century, our interdependence is already global, whereas our instruments of collective action and will-expression are as before local and resisting extension, infringement and/or limitation.
 
In the 21st century much of the power has evaporated from the nation-state into the supra-national, global space – while politics remains, as before, local: confined to the boundaries of the state’s territorial sovereignty. What we confront therefore is, on one hand, a free-floating power cut off from political supervision and guidance and on the other fixed and territorially-limited politics that in addition is bound to suffer from a perpetual deficit of power. 
 
Hence the essential problem is that the two abilities, power (that is, the ability to have things done), and politics (that is, the ability to decide which things need/ought to be done), conjoined for a few centuries in the institutions of the nation-state, now inhabit, as the result of globalisation processes, two different spaces.