Fri
05-Jan-2007

the plausibility of life

I've been reading The Plausibility of Life (Kirschner and Gerhart, 2005), a really readable and lucid look at the origins of "novelty" in biological evolution. I picked it up quite by accident last year and have been really enjoying it.

If Darwin was able to unleash the theory of evolution through variation and selection on the world, he was only able to explain selection. It is only in the last few years that developmental and molecular biologists have begun to be able to piece together an understanding of how variation, the raw stuff of evolution, is actually generated. How changes in the genotype actually manifest themselves as phenotypic variation, because there is quite a vast distance between the gene, on the one hand, and the anatomy, physiology and behaviour of the whole organism on the other.

One reason it is a very exciting topic because the ignorance around novelty is at the heart of scepticism about the theory of evolution, and there are few who have tried to make the link in accessible language between the big picture painted by evolutionary biologists and palaeontologists and the profound findings of the molecular sciences, mostly known only to those who can cope with quite difficult scientific jargon. So it's gloriously readable.

One of the big themes in the book is how much conservation there is in evolution, as opposed to change. For example, even distantly related organisms - like humans and yeast - use similar processes for cellular function, development and metabolism. These processes have been conserved for hundreds of millions or even billions of years. They form units that are recombined like lego bricks to facilitate the change that does occur in evolution.

In an early chapter they present an unusual history of the evolution of life, looking at the sweeping vista from the perspective of changes which emerge and are then conserved, with a moving "front" of evolutionary innovation.

At some time more than 3 billion years ago, the last ancestor of all extant life arose, probably a bacterium-like organism. It must have been enclosed in an impermeable membrane, had DNA, RNA, a genetic code for twenty amino acids and an energy metabolism based on the breakdown of sugars.

The universal ancestor split into two major lines of bacteria-like organisms around 3 billion years ago. One line led to the modern eubacteria (or "bacteria") the single celled microorganisms found all over the world today. The other line led to the modern archaebacteria, which today are only found in extreme environments like hot springs or hydrothermal vents in the ocean.

Among the eubacteria are the cyanobacteria (once called blue-green algae), which invented oxygen-generating photosynthesis, by which the entire oxygen atmosphere of the earth was slowly produced from water.

Then, around 2 billion years ago, the archaebacterial line split in two, one leading to modern archaebacteria, the other to eukaryotic organisms. This was a time of enormous evolutionary innovation as eukaryotic cells differ greatly from the prokaryotic cells of bacteria. The most striking difference is their size - eukaryotic cells are a hundred to a thousand times larger in volume than bacterial cells and are highly compartmentalised inside, with organelles like the nucleus, containing the DNA. Eukaryotic cells can engulf food particles, whereas prokaryotes secrete digestive enzymes into the environment. Rather than the impermeable cell wall of prokaryotes, eukaryotic cells maintain their shape with an extensive internal cytoskeleton. Most importantly, eukaryotes reproduce sexually. All these features have been conserved in subsequent evolution.

By 1.2 billion years ago, one of the many forms of single-celled eukaryote underwent changes conducive to multicellularity. That unknown cell was the ancestor of all modern plants, animals and fungi. In one line, a descendant leading to the plants engulfed a cyanobacterium, gaining the ability to photosynthesise in one step. In another line leading to the fungi, an ancestral cell with a strong cell wall specialised in metabolic versatility. In a third line leading to the metazoa (animals), the ancestral cell omitted a rigid wall and became a complex feeder, requiring a diet of whole cells to survive.

In the early period of multicellularity in the animal lineage, cells evolved modifications to suit a more social lifestyle, such as proteins allowing cells to stick together, or the epithelium, a sheet of tightly welded cells creating a sphere within which metazoans can create a hospitable environment for their cells to specialise, differentiate and communicate with each other.

All these innovations were conserved in the metazoan line as the front of dramatic evolutionary change moved away from cellular processes, to phyla (body plans). By 600 million years ago there were fairly complex multicellular animals, things like sponges, jellyfish and small bilateral worm creatures. Then, diverse macroscopic anatomy appears as if from nowhere 543 million years ago. This abruptness might be an artifact of the fossil record, or the result of some breakthrough in regulatory control at the cellular level.

From a bilateral ancestor which had evolved a through-gut with two openings, rather than the blind gut of simpler radial animals like jellyfish and hydra, around thirty different phyla of animals developed, each distinguished by a body plan which has been conserved to the present, with no new body plans emerging since then.

For example, in the ancestor of all arthropods (insects and crustacea) the basic body plan of the bilateral ancestor was modified to add body segments, appendages to each segments and a tough outer layer shed regularly after intervals of growth. The nerve cord condensed along the belly.

In the line leading to chordates and vertebrates, the nerve cord condensed along the back, a rigid rod developed internally from the roof of the gut against which swimming muscles worked, body segments were added in the muscle blocks that parallel the spine and gill slits were added.

Subsequent modifications in both these lines then involved shortening, lengthening, rearranging or modifying limbs and appendages, adding clasping or predatory mouthparts, and so on. There were occasional major novelties such as the sudden modification in vertebrates 370 million years ago of the lobe-fin to the autopod, the digits making up ankles and feet, but the body plans remained the same.

The authors speculate as to why improvements in these conserved processes, such as body plans, should stop accruing. Considering body plans, an interesting explanation is that if these were at first all unadorned, they were soon being fitted with armour, biting parts and appendages. Any new unadorned body plans that were developed would just be food for the better protected and armed established phyla. So the locus of evolutionary development had shifted from who could make the best body plan to who could make the best jaw and appendage on an adequate body plan.

I'll stop now. But I might do another post on it later. Later in the book, the authors are going to go into why it might be that the history of life on earth progressed in this way, rather than by every aspect of the organism being subject to continuous evolutionary change…

Mon
16-Jan-2006

narratives

During the lovely long holiday break in Devon I got through a few good books. I finished reading All That Is Solid Melts Into Air by Marshall Berman and read Richard Sennett's The Corrosion of Character. Both have got me thinking more about "narratives", a theme that also came out of reading Consciousness Explained by Daniel Dennett earlier in the year.

Daniel Dennett's book makes a long winded, but entertaining, case for consciousness - or the self - as a narrative entity, constructed from moment to moment, existing at no central, single point in the brain. It's an idea that has been proposed before by philosophers and writers, but Dennett sets it out from a materialistic scientific perspective. The book doesn't propose a single major breakthrough, or say anything that isn't built upon lots of other people's work. What it seems to be doing is trying to instil a different point of view in the reader, a different way of looking at the issue of consciousness.

Dennett's main point is that people find it very hard to discard the idea of a "central processing" area of the brain, a place in your head where a little soul watches all the information coming in from outside. His "multiple drafts" model of consciousness posits that activities in the brain are accomplished by lots of parallel specialised processes, interpreting and elaborating sensory inputs and initiating thoughts and actions. Thus one specialised module might be busy working out what colour something in the visual field is, and so on. As each of these sensory discriminations is accomplished it becomes available to other modules that can elicit behavioural reactions.

At any point in time, there are multiple "drafts" of narrative fragments at various stages of editing in various places in the brain. Which of these fragments are incorporated into "conscious experience" is not an exogenous act of supervision, but a part of the self-organising functioning of the network. There is no "central experiencer" who confers a durable stamp of approval on any particular draft.

Many of these different specialised modules can be precisely located in different parts of the brain and we also know that they take varying lengths of time to accomplish their functions, often as many as several seconds. Thus if consciousness is to be found in the actions and flows of information from place to place, then consciousness is 'smeared' spatially and, more interestingly, temporally.

Dennett describes an optical illusion where you have a red light and a green light next to each other, separated by only a short space, and these are flashed in succession. If the interval between the flashes is less than a second or so, the first light that is flashed appears to move across to the position of the second light. Furthermore, the light seems to change colour as it moves across the visual field. The red light will turn green as it moves across to the position of the green light, in effect changing colour before the green light is actually perceived. The intuitive explanation for this is that the conscious experience of the whole event must have been delayed until after the green light was unconsciously perceived. Another explanation is that the brain goes "back in time" and revises our memory of the moving light to account for what we find out once we have seen the green light.

Both these explanations apparently share a common error by supposing that there is a special time and place in the brain where unconscious processing become consciously experienced, or that there is an unfolding master record of "what really happened". In fact, a probe - "what is the light doing now?" - elicits the necessary information from the relevant specialised brain modules and we understand the light to be moving from left to right and changing colour in the order that the arrow of time dictates they should.

Another way of looking at it is that "time" does not exist in mental space. The way we understand time internally could be completely different from the way time actually works in the external world, except that if it bore no relation to objective reality then we would be very ill adapted to survive effectively. In order to mentally understand a spatial distance of say, two metres, between two perceived objects, the parts of the brain encoding our understanding of those two objects do not actually have to be two meters apart. We simply recall those two objects as being separated by a distance of two metres. Similarly, in order to understand two events as following each other in time, those events do not need to be encoded in the brain in the same order as they are understood to occur. We simply recall them as occurring in the correct order.

One perspective this book tries hard to inculcate in you is that there is no "conscious" or "unconscious" mind, in the way we often think of it. For example, when we talk about doing something "subconsciously" what we were really doing was "doing it" and then almost immediately forgetting the detail of what we were doing because it wasn't deemed important enough to commit to memory. There are various specialised modules in the brain carrying out various discriminations of sensory inputs, which then transmit effects to other places, contributing to further discriminations, and so forth. Some of these discriminations soon die out, leaving no further traces. Others do leave traces, on subsequent verbal reports of experience and memory, on emotional state, behavioural proclivities, and so on. There is no one place in the brain through which all these causal trains must pass in order to deposit their content "in consciousness".

Where this is relevant to my train of thought on narratives is that while we can understand all these self-organising brain modules as a piece of parallel brain "hardware", overlaying this is the conscious self, which exists as a resolutely serial piece of software, an abstraction that Dennett calls the "centre of narrative gravity". William Calvin, a neurophysiologist/anthropologist who I need to read more of, has said something similar about the surprisingly serial higher brain functions that overlap the brain's massive parallelism. Calvin argues pretty convincingly that human consciousness - "the self", even - is a cultural rather than a biological artefact. Though the brains of anatomically modern humans pretty much seem to have stopped evolving and growing around 100,000 years ago, it was around 50,000 years ago that "behaviourally" modern humans appeared, with the bewildering explosion of creativity that entailed. Calvin proposes that this was driven by the development of a new "mental operating system", characterised by the ability to serially string things together: phonemes into words, words into sentences, concepts into scenarios. He proposes that the development of long sentences - what modern children do in their third year - was the trigger.

Dennett and Calvin both seem to argue that this mental operating system is primarily based around the serial "talking-to-ourselves" consciousness of our internal narratives. This is where we do most of the work of trying to chain together thoughts and actions to explain the past and forecast the future. It might be the use of narratives that makes human consciousness apparently so different from that of other animals.

Arguably, the last two centuries of human experience have placed great strains upon this human ability to narrate the past and future. Marshall Berman's book - All That Is Solid Melts Into Air - focuses on the upheavals and renewals of the modern period, turning on an evaluation of the first section of Marx's Communist Manifesto, which celebrates the achievements of modern capitalism and its genius for organising human activity. If the power of capitalism lies in its very specific way of organising society, where all aspects of life are mediated by the market, then everyone within reach of this market finds themselves under the pressure of constant competition and so are forced to innovate and change, simply in order to survive. What Marx described vividly as "uninterrupted disturbance, everlasting uncertainty and agitation" distinguish the modern era, where "all fixed, fast-frozen relationships, with their train of venerable ideas and opinions, are swept away, all new-formed ones become obsolete before they can ossify".

Marx, and Berman, propose that in this environment modern people must learn to embrace change, to thrive on renewal and look forwards to endless growth and development. Yet while the "uncertainty and agitation" of capitalism is exciting for those who are able to make themselves at home in its turmoil and create meaningful narratives for themselves, for most it is a shaky edifice on which to build a sense of self. If we are in a state of perpetual self-development, of endless becoming, then perhaps there is never a clean moment of arrival, or a clarifying moment of change that illuminates the whole.

I like the idea that the modern environment has uniquely undermined the narrative software that human brains and societies have constructed over the millennia. Capitalism itself seems geared towards increasing discontinuity. Its mighty creations are disposable and capitalised for fast depreciation, built-in obsolescence insuring shorter and shorter lifetimes in an accelerating cycle of production, destruction and consumption. David Harvey, the economic geographer, has tried to show how the repeated intentional destruction of the built environment is integral to the accumulation of capital.

The modern era has presented the discontinuity of the self as a theme in some of its greatest literature. For me, the writings of Fernando Pessoa (The Book of Disquiet) convey this most brilliantly. At times he seemed to be able to confront the strange flimsiness of modern consciousness and put it straight down on to paper in flashes of brilliant writing.

I am, in large measure, the selfsame prose I write … I've made myself into the character of a book, a life one reads. Whatever I feel is felt (against my will) so that I can write that I felt it. Whatever I think is promptly put into words, mixed with images that undo it, cast into rhythms that are something else altogether. From so much self-revising, I've destroyed myself. From so much self-thinking, I'm now my thoughts and not I. I plumbed myself and dropped the plumb; I spend my life wondering if I'm deep or not, with no remaining plumb except my gaze that shows me - blankly vivid in the mirror at the bottom of the well - my own face that observes me observing it.

Marshall Berman argues that by looking back at the roots of modernism in the eighteenth century, we can draw on a two hundred year history that can give our fractured modern lives some form and meaning. But perhaps capitalism has gone on to accelerate its assault on the coherence of life narratives. This seems to be the theme of Richard Sennett's fascinating book on The Corrosion of Character. Sennett proposes that the conditions of the "new capitalism" increasingly create a pervasive insecurity in the lives of those who live and work within it. More than ever before, the flexibility and short-term nature of modern capitalism corrodes those qualities of character which bind human beings to one another and furnish them with a sustainable sense of self. This is particularly evident in the organisation of working time.

Just as the market's increasingly impatient demand for rapid returns on investment has reshaped corporations into flexible, flatter organisations - managed increasingly as "networks" rather than "pyramids" - so workers find themselves undertaking increasingly short-term, episodic, flexible jobs. This erodes both commitment and trust - which are social bonds that take time to develop, "slowly rooting into the cracks and crevices of institutions" as Sennett so nicely puts it. In modern institutions, weak, fleeting forms of association are more useful to people than long term associations. Such weak ties are embodied in "teamwork", in which the team moves from task to task and the personnel of the team changes in the process. Values such as loyalty and service are quite inappropriate in the new capitalism. Nor is long term experience or the development of a single set of skills useful - for most, the ability to adapt and change your skill base on demand makes you much more attractive to employers.

This creates a conflict between the values that should underpin social and family life - formal obligation, trustworthiness, commitment, purpose - and the values that underpin the flexible short term nature of modern capitalism. If working life has largely come to consist of episodes and fragments, it becomes harder than ever to develop a serial, linear, cumulative narrative of identity. If you have no sense of your character unfolding or your ideals evolving, then uncertainty and confusion are likely to follow.

Sennett suggests that the capacity to let go of one's past and the confidence to accept fragmentation are two traits of character which appear among people truly at home in the new capitalism. This is great for those at the top, but much more self-destructive for those who work lower down in the flexible regime. Work is what we do most of the time, and it does define us. Perhaps it is unhelpful when work reminds us that we are scraps of random material, a discontinuous consciousness constantly trying to re-remember our own lives according to arbitrary stories that we project back into our pasts, as we try and predict an uncertain future.

Thu
03-Nov-2005

fireball comics

Our friends Abi and Kevin have set up their own online comic book selling website. Have you been meaning to buy The Dark Knight Strikes Again lately?

Thu
09-Jun-2005

book meme thing

This looks almost as destructive as that bout of Top 50 Albums me and a few others recently indulged in after Beltane. Jim has just forwarded me the book meme thing.

Number of Books I Own
Hmmm, there's a load I keep at the parental abode in Devon, and a few I keep here in London. Can't be more than 300 or so though.

Last Book I Bought
Mutants by Armand Marie Leroi. This is what I'm reading at the moment - it's an absolutely fascinating look at what genetic and developmental mutations reveal about the way the human body is grown and ordered. There's all kinds of interesting stuff in there. I'm just reading about the the female spotted hyena, which has a huge clitoris relative to all other mammals. The spotted hyena clitoris actually has a urethra and becomes semi-erect in dominance displays. There is no vagina and also what appears to be a scrotum, though this is actually a pad of fat tissue. It seems that in developmental terms, the spotted hyena female is a pseudohermaphrodite, a female that has been partially masculinised in the womb. In this species, this mutation has become the norm, and though the evolutionary costs are high - females give birth through the clitoris and the first time they do so the clitoris is so narrow that birth takes hours, 60 per cent of the cubs suffocate and 9 per cent of the mothers die - they are not insurmountable.

Last Book Read
I finally got round to reading Daniel Dennett's Consciousness Explained which, while it doesn't explain consciousness, does a very good job of demolishing lots of fallacies about the nature of the brain and the self. It's also very witty and well written, which is always pleasant in a science book. His central concern is to kill off the ghost in the machine, or the soul, and his main observation is that despite the apparent unity and continuity of our experience, consciousness does not involve the existence of a single central self, but can be understood as a collection of perceptions and thoughts mapped to parallel, multitrack brain processes. There are some very weak bits on memes and the evolution of consciousness where it all gets a little too sociobiological, but even here there are some beautiful little thought experiments and speculations. One is the idea that consciousness evolved with language out of primates talking to themselves. They began by making noises signalling things to other members of their group, such as "danger" or "fruit", but also found themselves making these noises when there were no other members of the group around. In such circumstances, the brain process sending out the signals about fruit finds itself communicating, via the animals own mouth and ears, with other brain processes that it does not have a direct neural connection to internally. As a result it comes to better levels of understanding about its environment and in time this talking to yourself becomes an internalised, stream-of-consciousness mechanism.

Five Books That Meant A Lot To Me
Lewontin, Rose and Kamin Not in Our Genes
Hermann Hesse Siddhartha.
TS Eliot Selected Works
Philip Pullman His Dark Materials Trilogy
Olive Skene Johnson The Sexual Rainbow: Exploring Sexual Diversity

Passing this on to
I don't have any literate blogging friends. I'm sure Tom P'll do a list once his blog is up and running again.

Sun
07-Nov-2004

managing britannia

I recently finished an excellent book called Managing Britannia, by Robert Protherough and John Pick. It's about the way that the idea of management has come to take over swathes of British life, bringing its own ethos, rules and vocabulary, imposing them on organisations which worked well beforehand, and wrecking them.

The book is quite polemical, but it mainly deals with areas where the effects of modern management has been particularly corrosive. The chapters where idiocy is most plain are those on schools and universities, and the NHS. In education, it is plain that the assault on the professional independence of teachers and the proliferation of central targets and tests and reforms has had appalling consequences. The chapters that criticise government attempts to understand the arts as an 'industry' are entertaining (particular disdain is piled upon Chris Smith in his time as Culture Secretary) but not always convincing. The authors are inclined to see the creation of DCMS and its forebears as a Stalinist project.

I like the way that they book points out how all this began in earnest under Thatcher in the 1980s. Despite their neoliberal rhetoric about 'little government' it was the Tories who oversaw the initial proliferation of central government management over every sphere of human life and endeavour. Blair and the control freaks of New Labour emerge as the natural heirs of Thatcherite Conservativism in their relentless multiplication of management bureaucracies and their ambitious attempts to bring all of British life under the tedious reductionism of evidence-based policy.

Sun
03-Oct-2004

you are g8, we are 6 billion

Have just finished Jonathan Neale's book You Are G8, We Are 6 Billion, an inspiring account of the G8 Genoa protests of 2001. It is very engaging and readable and has chapters summarising the issues at stake as well as chapters charting the protests as they emerged over the weekend of the G8. The chapter on 'Oil, dictatorship and war' is a particularly cogent explanation of the roots of the conflict in the Middle East and the role of oil and US geostrategic ambitions in shaping the world economy.

Wed
30-Jun-2004

the origin of capitalism

I have just finished the Origin of Capitalism by the excellent Ellen Meiksins Wood. This is my first step towards trying to articulate a coherent anti-capitalist standpoint. The book is very short, readable and good.

Its starting point is countering the increasing universalisation of capitalist logic by outlining capitalism's historical peculiarity and transitoriness, to defamiliarise much that now seems normal and natural. This certainly doesn't have to be a left-wing or anti-capitalist endeavour, and I read the book only as a refreshing attempt to understand where the current capitalist system has come from and what it really is. A look at its historical specificity rather than a polemic against it. It is particularly good for delineating the boundaries of capitalism, for separating out modernity, urban life, technological advancement, bourgeois revolution and other things that have been bundled up with it, and that help to make the strange case that it has always existed in some form or other and only needed the right conditions or opportunity to be fully realised.

Wood roundly vanquishes the sloppy notion that feudalism as a system was always somehow transitional to capitalism, and that the growth of cities, trade and commerce inevitably lead to its development. She observes that there have been sophisticated technological developments, urban cultures and trading networks both in the European and non-European worlds that did not see the emergence of the specifically capitalist market imperative. Trading networks have long been based on the circulation of goods, rather than on intensifying production in the manner of a market society. Goods are brought cheap in one market, and sold at higher prices in other. In the capitalist market society that first emerged in the rural southeast of sixteenth-century England, there is just one, unified market where profit is derived from the intensification of production, through competition economic improvement rather than trading. Capitalism emerged in this one time and place, out of a unique reconfiguration of land, landowners, agricultural tenants and agricultural labourers in the countryside, turning around the famous Enclosure Acts of the seventeenth and eighteenth centuries. The emergence of a proletariat and an urban capitalist class were driven by capitalism, rather than the other way around, though the emergence of a mass proletariat enabled capitalism to expand massively, and it has been expanding and colonising ever since. Its roots are agrarian.

What this means is that capitalism is not about the 'bourgeois' revolution of the Enlightenment and the French philosophes, nor about technological or rational improvement, nor are cities inherently capitalist, nor is 'modernity' necessarily capitalist. Capitalism is a very specific way of organising society, where all aspects of how you live your life are mediated by the market. Capitalism's strength is that it colonises, bringing more and more areas of life into the market system. The turning point for Wood, where society becomes truly capitalist, is when that most basic of commodities, food, is only obtainable through the market system.

I think this may help in my quest to work out where I stand, since so often, opposing capitalism is taken by its knee jerk defenders to mean opposing many other things which are not in any way capitalist and which have predated and will postdate the capitalist system. I'm thinking here of cities, representation (democracy), modernity, technological development, science, rationality, a nice beer, and so on...