Saturday, 19 September 2015

GM debate : ignorance of reality is no defence.

http://www.theguardian.com/environment/2015/jun/25/gm-wheat-no-more-pest-resistant-than-ordinary-crops-trial-shows



boolybooly
And now we have a bunch of gene spliced pollen floating around the countryside fertilising next years seed corn.

fizzgog
From http://www.theguardian.com/uk/2012/may/01/anti-gm-activists-wheat-rothamsted:
To prevent stray pollen the Rothamsted scientists have surrounded the trial plots with 10 metres of barley and three metres of conventional wheat.
No cereals or grasses are grown within 20 metres of the border. Wheat pollen is heavy and travels at most 12 metres.


boolybooly
These precautions @fizzgog are totally inadequate to prevent contamination. They have been conceived within the wrong paradigm, they are designed to reduce the statistical likelihood of a single pollen grain passing to a food crop but where you are dealing with billions of pollen grains in a real world situation, a small statistical chance for one grain becomes a statistical inevitability for many many thousands.

It bears comparison with the reason that the Nazis did not develope the nuclear bomb, they believed the statistical likelihood of a single neutron collision required that it travel through many meters of plutonium, what they didn't consider was what the allies understood, which is that not all the neutrons need to collide to generate a self sustaining fission chain reaction. Only a smaller proportion need to collide, a statistical inevitability where billions are involved. Their huge error meant they believed a nuke had to be made of tonnes of material and so they did not persue the idea when in fact the critical mass for plutonium 239 is about 11 kg.

These field trial precautions fall foul of the same kind of mistaken interpretation of statistics. The contamination of the food crop with genespliced pollen was inevitable using these protocols, it has already happened.

Consider the case where there is a local eddy which can pick up much heavier objects than a breeze and transport them to altitude thus moving them far further than laboratory based experiments predict. This is due to the low pressure tube which forms at the middle of any vortex and sucks in medium like a vacuum cleaner. They dont have to big, even a dust devil would shift pollen a lot further than 12m and a strong turbulent persistant wind will tear the lab based statistics for pollen distribution to shreds as turbulence creates multiple chaotic vortices. Its absolutely unconscionable to expose the UK countryside to experimental windborn GM pollen.

Not even one grain of pollen should be allowed to escape. Genetic contamination does not require that a whole field be pollinated, it requires only that one seed planted for next years crop be fertilised by this years genespliced pollen.

http://www.bbc.co.uk/news/world-asia-27298939





http://www.telegraph.co.uk/news/earth/agriculture/geneticmodification/11702744/Anti-GM-protesters-dont-understand-how-science-works.html#comment-2104389847


flyingfox (aka boolybooly)
The article above is predicated on a straw man argument. Many GM critics are highly qualified and well informed biologists. The people doing GM work are not all of the same caliber and have been hired by profit motivated companies flush with finance to play with forces they do not seem to understand. 
The design of this experiment was negligent and unsafe and has ensured that modified genetic material will have escaped into the environment and will now become part of the wheat crop in the UK whether it was successful or not, whether it was safe to eat or not, we will soon be eating it.

Critical Party

I assume that the critic "scientists" you're referring to are people like Seralini, Carmen, and Seneff? People that have been thoroughly lambasted for poor science by regulatory agencies across the board. 
Also, your second paragraph is hilarious. Your knowledge of how genetics works is clearly completely nonexistent.

flyingfox
I am afraid you have that backwards, it is you who does not understand. I am not trying to slap you down or anything but FYI and because you brought it up I have studied evolution and genetics at a reputable academic institution :) please feel free to troll away if it makes you feel good.
If ignorance is no defence in law, it certainly will not protect us from reality. The experimental design ensured that wind borne pollen has escaped, it does not take a field full of GM wheat for next year's wheat crop to be contaminated, it takes only one pollen grain to fertilise one seed and for that seed to be planted among next year's crop for the genetic modification to become established in the food crop gene pool. The theory of evolution by natural selection depends on the possibility that mutations happen only once but can be inherited by an entire species due to the process of gene fixation. This is because where one individual organism reproduces it can create more than one offspring eg the many seeds (and pollen grains) of a wheat plant seed head. Where offspring inherit an advantage they will reproduce better than competitors without that advantage, but even where a genetic difference confers no advantage the frequency of GM chromosomes will still persist in the gene pool alongside competitor non GM chromosomes and can potentially increase due to a process termed "genetic drift". We know this already.
However the conception of this experiment has been criticised on the basis that aphids respond to changes in pheromone concentration, so are not deterred by an even and constant spread of the chemical across an entire field ie they become habituated to a constant concentration and only respond to a sudden increase signalling an alarm. Where contaminating seed grows in an environment where it is one plant among many without the modification it might potentially be granted an advantage not evident in the experiment precisely because it is present in small numbers within a host crop, creating localised maxima of pheromone concentration so that an aphid arriving at a GM plant will encounter a relative rise in alarm pheromone and be repelled to nearby plants without the pheromone, which means that there may be a selection pressure which will raise the frequency of the contaminating GM genotype to an equilibrium point within the gene pool where it no longer confers an advantage because too many neighbours have the same pheromone. Such a gene would never reach fixation in a monoculture crop but would never be extinguished either because where it became rarer it would become advantageous again and so would always be present.
The point is we don't know whether this can happen but the lab experiments suggest it is a possibility. But that is the point, ignorance is no defence in reality. These field experiments should never have gone ahead in the open without proper laboratory background research into the phenomena they are trying to exploit. In this case the failure shows the experimentation had not been done adequately.
But there are also other real world reasons for caution which are being completely ignored by open air experimentation. All GM product should be treated as biohazard until food trials have been conducted to ensure pleiotropic effects or the reawakening of epigenetically suppressed genes has not allowed any carefully bred out plant defences or other toxity to result. They should certainly not be allowed to contaminate food crops. I fear it will take a disaster on the scale of an industrial accident for biotech companies to take genetic safety seriously.
These companies are playing biological roulette with your daily bread. With this trial the damage has already been done and we will just have to cross our fingers and hope for the best. There is nothing else we can do except ensure that local wheat farms for a 5km radius do not allow their wheat to be used for seed next year.

Monday, 15 June 2015

Our priority must be to defend the Earth not create an elitist enclave of narcissistic boffins on Mars.

I know it looks like I am hitting on Professor Hawking for which I am sorry, as this is the second article in a row in this blog to reference one of his media statements. But he does say interesting and sometimes controversial things which do seem intended to stimulate thought.

Some time ago, spurred by reports of Stephen Hawking's express desire to see humanity live in space I felt it appropriate to respond with a consideration of the correct ordering of priorities for humanity at this time. An interesting interaction ensued. As I explained I didn't mean it unkindly but I think it makes more sense to look at this from a different perspective.

http://www.telegraph.co.uk/news/science/space/7935505/Stephen-Hawking-mankind-must-move-to-outer-space-within-a-century.html


flyingfox 5 years ago• Our priority must be to defend the Earth not create an elitist enclave of narcissistic boffins on Mars. 
finsburyparker • It's thanks to your so called 'Narcissistic boffins on Mars' that you have access to this medium you are using to berate them! G. P. 
flyingfox •The boffins who invented the internet did not live on Mars (to the best of my knowledge) ! The reports we are seeing of Prof Hawking's thoughts have been dumbed down, my reply was intended to match the level of the discussion. Sorry if it seemed a little terse, I was having trouble making myself heard due to obstructive interactions between Disqus and Twitter which erased my first attempt so I tried to keep it short and pithy. 
 Am I calling all boffins narcissistic? No, only those Zardozesque straw boffins who would hypocritically condemn and might wish to escape from their fellow humans, rather than face their own flawed humanity and defend the only place we can call home from the danger of asteroid impacts.
 This would be the primary justification for journeying further into space than Earth orbit of sufficient urgency it can be countenanced when there are people dying in squalor all over the world, when we have not learned to husband our resources or to cherish rather than defile our environment or balance our population at sustainable levels, let alone switch to renewables, so that we may continue to live in sustainable comfort, with a clear conscience, in the one place we can call home. 
 The more we understand about the universe and our own evolution, the more we recognise that this planet is priceless, irreplaceable and indispensable to the future of humanity. If we have learned anything surely it is that there really is no place like home. 
 Asteroid impact is the one thing we cannot afford to let happen while we sort these other things out and this justifies continued investment in astronomy and space exploration, but these other things must be sorted not run away from or they will follow us wherever we go and our self inflicted torment will never end.

To comment further : IMHO The escapist tendency within the culture of science finds a creative outlet in science fiction in which space exploration is a trope for leaving the woes of the human condition behind. Much of this woe springs from the battle for civility within our own societies, the battle between brain and brawn within the body politic of our governments and academic institutions is a recapitulation of the battle between individuals who specialise in developing either. I am talking about geeks versus jocks. The truth is we need them both, not just as a society but as individuals, we need both. Ideally jocks need to get smart and geeks need to stay fit and healthy, or to look at it another way we all need to strike a balance between the inner geek and jock.

As I see it, much as space colonisation may have been an inspiration for the Star Trek generation, myself included, there is no practical way to escape this Earth of ours on a permanent basis within the next century because of the vast infrastructure which would be needed to support a breeding population anywhere else.

We take for granted all the things which Earth does for us and its time we didn't. It is time we recognised that the Earth is priceless and I cannot agree that we should ever treat it like a disposable item, in any case its not that simple.

Our survival even in the case of an extinction event asteroid impact would depend not on running away to space, but in the worst case it would depend on sustainable subterranean civilisation which would be far easier for us to do as we simply do not have the muscle to launch 1000 people, plus maternity hospital, plus resource gathering infrastructure and refining and manufacturing plants into orbit. Even if we had the ability to construct gravitational environments on a sufficient scale that they would be sustainable, which as yet we don't, the cost of putting them in orbit let alone on Mars would be, well, astronomical.

We would get far more for our money by burying everything we need below the protective skin of the Earth's crust and get gravity for free. It just makes more economic sense, not that I don't like the idea of getting away from it all, it just wouldn't work, not yet awhile.

Saturday, 14 March 2015

On Aggression

Stephen Hawking recently commented that ...
“The human failing I would most like to correct is aggression”
This is something which piqued my curiosity as an undergrad', so I felt it was worth contributing a few thoughts to the discussion in the media which Professor Hawking's comment made possible. Below is a reply to the article linked above, which summarises some key reasons for optimism about the human condition which result from the contemplation of biological knowledge, which I hope others will find interesting. 

I also plugged Konrad Lorenz's book "On Aggression" on which some of these ideas are based.

If one wishes to correct aggression one needs to understand the biological causes for it, its behavioural context and behavioural counterbalances like peacemaking, friendship and love which in the natural state inhibit aggression in appropriate circumstances.

Aggression is a part of us all. Even academics are aggressive in their own way and it would be hypocrisy to say otherwise and we all know that kind of hypocrisy is no stranger to religious fanatics either.

At the root of all our behaviours is natural selection which exists because self reproducing DNA reproduces more successfully the better it is at reproducing, obviously. OK we are competing for limited resources and winning can be a matter of life and death and that is the reality. For social animals like humans winning has a lot to do with making friends precisely because life isn't fair and contests of power between groups of equals become a numbers game. Consequently we have all that we need to solve the problems of aggression and live as friends should circumstances permit. In today's world those circumstances are of our own making.

In an aggressive world one needs to be aware of reality to survive but we can improve on the past. The numbers game is real but for example, given the right circumstances, democracy can win, because it pleases most of the people some of the time. Its not perfect but its usually better for everyone than war and revolution.

This is why I think it would help if more people understood the biological basis for our own psyches because this is as close as we have come to understanding our own reality and consequently offers us some chance of finding ways to remedy recurring patterns of violence. Such as the traps of tribal antagonism, since this is like a knee jerk reflex response for the human mind grappling with its group identity when it has no other frame of reference by which to assess its own emotions or clear understanding about the disgrace which such attitudes inflict on us today.

Nevertheless, even within a scientific context, the greatest obstacle between us and a peaceful cooperative life is ourselves, since understanding others is predicated upon such. One could do worse than starting with "On Aggression", a book by Konrad Lorenz, a noted ethologist, which is where my journey towards understanding my own and others' aggression began.

Thursday, 21 March 2013

Is Everyone Around Me Conscious?

This was posted as a Yahoo question. I did my best to answer as below.
Are you? If one can surprise oneself or learn about oneself then one's mind is greater than its apparent working knowledge of itself. Are you fully aware of your own mind? IMHO to the nascent human mind the answer to your question is "probably", their body is the same shape as one's own body, they react to things the same way, hot and sharp are painful to them too, food is good etc, they can tell one things with their actions or by gesture or language that make sense to one's consciousness, so it is likely they have a similar consciousness to oneself, but that does not mean identical. Some seem more similar to oneself than others. In educational theory this process of becoming aware of others is regarded as a developmental process and is studied as the "theory of mind".

One apparently has no direct awareness of others' minds since they can act in ways one did not predict, unless of course humans evolved protean behaviour, like flies, as a means for obfuscating prediction and evading telepathic predation. So while it seems likely that one can only deduce the existence of another mind and its character by inference from sense data, we cannot be certain we are fully conscious of all types of sense data being employed. Though whatever the kind of sense data involved one can still only guess at what others think, as a reflection within one's own mind and as a projection of one's own thoughts.

So while consciousness in others can only be attributed as an extension of one's own by sympathy this does not mean this consciousness does not really exist in the same way that imaginary phenomena like fantasies do not really exist, because the nature of other's minds is infered from sensation not invented (unlike Tinkerbell). So it seems likely the capability to sympathise and project have evolved to permit prediction of others' behaviour, because this is the prediction of something real, something sensed in our environment which acts autonomously and which can directly influence survival and reproduction, be they spouse or mother in law!

But if one's own selfconsciousness is incomplete, how then can one's awareness of others ever be complete? Conversely one can sometimes see in others truths about human nature which one denies in oneself yet which must be in fact a part of one's nature for one to be able to conceive of it.

This is why I studied animal behaviour as a zoology undergrad, in part to learn about human nature, because everything one sees in animals, as in others, is subjectively a reflection of oneself and objective scientific data about animals and conclusions abstracted from it are instructive in the principles of evolution which in all probability shaped my human consciousness. Thus by sympathy on the one hand and principle on the other, all the natural inhabitants of the planet can be a muse, in a way that another human being may not, since with animals one may remark on truths that social and political constraints prohibit revealing in the contemplation of human nature.

That is where I ended my answer. To sum up my perspective on this, one's awareness of other peoples' consciousness is directly related to one's awareness of one's own consciousness and vice versa, one's awareness of one's own consciousness is directly related to one's awareness of other peoples' consciousness and this is because we have evolved to use our own brain to as a model by which we may understand other peoples' brains, which is the basis of sympathy, the inevitable and inescapable result of millions of years of social evolution.

What we choose to do with our faculty for sympathy is a moral / socio-political decision each of us must make which can have a profound influence on the course of our lives and this too is inevitably subject to the process of natural selection. I wonder where it will take the human race a million years from now?


Monday, 31 December 2012

The biological soul, rationalising the body-mind duality.

Human beings have evolved, there is no way round it. This means that everything we perceive comes to us through senses which evolved, into a mind which has evolved, eliciting emotions which have evolved because of what they make us do.  After bodily health it is our behaviour which determines the evolution of our genes. Our purposes are the purposes of the survivors of billions of years of evolution. To understand ourselves we must understand evolution.

When I was young I frequently encountered a school of thought which dwelt on the "body - mind duality". The idea was simple, that human beings had a body and they had a mind which were different and separate. It made assumptions underpinning common attitudes and professional paradigms. It was a hangover from prescientific religion and many people I met were perplexed by it because they knew deep down that it doesnt make sense. But people would not bother to question it openly, there was too great a disadvantage in stepping outside the norms and questioning fundamental assumptions. It was best for each individual to proceed on the basis of the common culture and not to go against the flow.

This dichotomy stemmed from the even older metaphysical notion of flesh and spirit, giving rise to the idea that human beings have a distinct soul. This is not a scientific idea, but is a very old shamanic concept which always has subserved political reality as a metaphor for "the big picture" by which means the human conscience has been projected as the soul and its deliberations portrayed as metaphysical phenomena. Inevitably it has been used for political purposes and reformed by the machinations of religious academia attempting to conceive of an ideology sufficient to serve the struggle for power. The differentiation between body and soul has been elaborated on in the attempt to come to an arrangement between individuals over relationships of power expressed in theocratic terms.

This explains why the notion is so firmly entrenched in the culture of my country. It has been a way of discussing the surrender of individualism to a culture of negotiated mutual support. You can understand why negotiations backed by force of arms were handled by displacing the discussion into a spiritual context. Religion was the diplomatic alternative to open war and preferrable to many who might otherwise die on the battlefield.

The legacy is long lasting. Even today works of popular fiction like Buffy the Vampire Slayer and a slew of similar cryptoreligious works still reflect the same dichotomy of body and soul and everyone seems to know what they are going on about even though it makes little sense to a rational eye.

As a scientist other perspectives were available to me in youth but I had no way to know which was truest because in science truth requires hypothesis testing and all attempts to discover quantifiable aspects to spirituality had been discredited. There was no data, which is itself mystifying. The subtext was that spirituality was bunkum even though that is not a scientific position to hold without evidence. To a child that is perplexing, it takes the perspective of adulthood to unravel the complexities of human politics which created the spiritual dichotomy of body and soul. But like most people I wondered why so many believed, or at least acted though they believed, something which others denied as bunkum without evidence, based apparently on a subculture of prejudiced scepticism.

It struck me that both traditions of belief and scepticism rely on received wisdom by virtue of being traditions, in that people tend to adopt one or other attitude under the influence of someone older who they emulate and repeat the arguments of the past and try to develope them. So they constitute competing cultures developing alongside each other, but the fact is the sceptical culture exists as a reaction to the religious culture since it has nothing to say other than that these people are mistaken. So it can never win, it can only dimiss the attempt to pacify those bent on conflict by spiritual means. This is not an entirely constructive thing to do if one has no better means of conflict resolution available.

So people of my generation have looked to other cultures to understand their religions and means of conflict resolution and methods in the persuit of peace. I took an interest in hinduism and buddhism for example, a bit like the Beatles. The hippy era was all about peace, the punk reaction tried to be honest about base human emotion and antagonism because ideals werent working. The 90s just tried to cover it all up again. In the 2000's we started a new war and are back to square zero. I am not sure if we learned anything at all.

I think future progress lies in the direction that we need to take responsibility for ourselves and stop projecting good and evil outside ourselves and accept them as our subjective perceptions of a real world. Its going to be an educational necessity in a future where tribalism and territoriality dissolve in a world wide community of humanity. So little by little we must try to develope our culture, both the believers and the skeptics.

There are other perspectives we could try. For example it is more likely the body and mind are one thing, the difference between them imaginary. The evidence of science supports that idea and so does the philosophical method of Occam. In this view both body and mind are objects created in the minds eye by the mind itself to encapsulate and discuss different aspects of our experience.

So from where I sit the soul is not separate from the living body but is in truth one's own concept of one's reputation in the eyes of others. The division between them is not due to two items coexisting in the same place, or a split mind, it is the interruption of volition by cognition, the regulation of desire by thought. Thoughts which are as much a part of oneself as the desires they govern and the foundation of a moral relationship with the rest of humanity. The metaphor of the soul has been used to educate generations of people to listen to their conscience by reminding them that even if they appear to get away with offences against other people i.e. they survive an action without injury, there is still something of their action which persists even once an action is over, something which can have repercussions later on. In other words the impression you make on other people can return to haunt you. This is the nature of your soul and the reason it is true that it persists even after death is because those who live on can still remember you and their memories can influence the way they treat your surviving relatives eg children. For evolutionary purposes this matters, which is why it matters to us as individuals. We know that what is precious in life is greater than our own individuality but to date we do not have the intellectual framework to recognise why. The reason why is that evolution makes us altruists, we cannot help it, the genes in our fellow humans are as precious to us as our own, sometimes moreso and evolution has endowed us with the equanimity to recognise this and the inclination to act upon it and the sympathy to feel the pain of others as if it were our own. This is the truth about the legacy of evolution in the human heart and the dogma of selfishness and competition is not the whole truth about human nature but is merely one pole of the entire world of human motivation, the other pole is our awareness of the rest of humanity and their importance to us.

The idea of the soul has long been a moral metaphor which attempts to discuss the feelings we have about our reputation and has validity in that context but taken too far this idea has been mistakenly interpreted as suggesting consciousness was separate from the body and persisted after the body had ceased to live. The elements of that idea have their roots in reality but then the stems grew twisted in confusion, by which I mean the elements are not put together right, yet they are close enough to truth that despite the confusion they can guide actions sufficiently well that the confusion can continue despite the inevitable contradictions that attempting to live by these mistaken ideas reveals.

The reason such errors of thought persist is that they cause pleasure of a kind and this addicts the minds of some people and addiction of this subtle kind can turn delusion into psychosis which can then spread itself by immitation and sympathy. This is the problem and each such delusion is the beginning of a new cult. The idea of a distinct soul implies that you can escape death which is a great relief to aging humans. Yet most people know you shouldn't take it literally. As deep down we understand it is a vanity, a private conceit and an overestimate of ones true capabilities but some people prefer to live in hopeful delusion because the idea of death is troubling and painful and this creates an aversion. These two, addictive pleasure and repellant aversion, are enough to turn the mind from sanity to ever more grotesque delusion.

If one accounts for the repulsion of morbid fear and the attractive fantasy of eternal life one can begin to appreciate that the separated soul is truely the delusion of a single living being with a neurologically integrated mind which is moved by its instincts to maintain constructive relations with the rest of its kind in preference over conflict and enmity which might lead to its own demise, providing its evolutionarily set requirements are met. Yet even after the scientific enlightenment many thinkers and academics of all shades were for centuries confounded by the difference between the mental and physical self, for example with respect to mental and physical illness and the legacy of that remains with us today in the way mental patients are treated with a different paradigm to the way patients with other illnesses are treated. I have come to the conclusion that there is something about the way our brain functions biologically which perpetuates that perceptual dichotomy.

If one looks on the body and the mind as both sensory experiences within a consciousness created by a more or less coordinated and self aware nervous system, the difference between the two is in reality a difference of perceived location. The sensations arising from the body are referred to the body's form as we conceive of it because it is in our biological nature to grow up with the sense of a body. It is through this that we learn to coordinate our physical actions with our senses and appetites and our nervous system is hardwired (somatotopically) to facillitate that process, the spatial relationships in the pattern of bodily innervation are reflected within the pattern of sensory and motor nerve fibers in the brain. We evolved to have a very strong awareness of our own body and the instincts to keep it alive, so this naturally has the priority over other forms of cogitation and dominates our perceptions.

The sensations arising in the mind as abstract thoughts and ideas by definition do not have the same strong sense of location as sensations arising from the body, so it is possible but mistaken to conceive of them as occurring somewhere else than the body, on some other 'plane' for example, which would explain much historical philosophy and metaphysics. The observations of science tell us they are not really somewhere else at all, even though sometimes people believe they are. The true location of such thoughts is inside the body, inside the nervous system but without the same kind of certainty about their location that bodily perceptions evoke it is possible for us to imagine all kinds of things about their nature and place in the cosmos which are unreal. This is why cults of delusion arise and persist and why humanity continues to struggle with the body mind duality when in reality these are simply two aspects of the same awareness, both occurring in the same location, one aspect of awareness dedicated to coordinating the body the other dedicated to considering what our senses tell us exists outside it and how it might be useful in the task of staying alive and fulfilling the purposes of our evolved being.




Thursday, 5 April 2012

The Origin of Life.

An article appeared in The Independent newspaper entitled ...

(by John von Radowitz)

... summarising recent research lead by Dr Jennifer Blank (Nasa/Ames Research Centre) showing that comets could have delivered amines to the surface of the newly created Earth.

My take on this was that while interesting, the bigger question is whether bacterial cysts could also make the journey because the climatic variations in the environment of a small dying planet, losing its atmosphere and subject to harsh seasonal extremes, would lead to evolution by natural selection preadapting bacterial cysts for survival in deep space, as stated below. In addition it seemed worth discussing the chemistry of self replication since the more we know about it (eg Philipp Holliger et al's recently publicised XNA experiments at the MRC molecular biology lab) the less of an inexplicable or unpredictable event the origin of life appears to have been.

In 1989 Thomas Cech and Sidney Altman were awarded the Nobel Prize for Chemistry for their discovery of the catalytic properties of RNA. Since RNA has both self replicatory and enzymatic powers this makes it, or something like it, a good candidate for having been the living molecule which preceded the evolution of the cell. Since pyrimidines (the building blocks of RNA) can be synthesized from amines and amines are known to be synthesised from the simple molecules which abound in the universe and collect on the surface of planets, this implies that in the huge expanse of cosmological time preceding the formation of the Earth it is very credible that life evolved elsewhere first and raises the possibility that some of this may have seeded Earth before life had time to evolve here of its own accord. So I joined in the comments section and reproduce my arguments here with a few embellishments.

In short it seems possible to me that given the relatively short time between the hypothesised planetary collision which created the Earth-Moon system and the beginnings of life, the Earth was seeded by an intact organism which first evolved on a planet in a different star system. 


Commentary.

Life origin theories still dogmatically avoid any consideration of undirected panspermia as once favoured by Hoyle and Wickramasinghe. I would have thought it was not impossible for comets to first preserve and then disperse entire bacterial cysts when passing between the Earth and the Sun. Cysts might enter the interstellar medium from, impacts with or directly from the outer atmosphere of, dying planets slightly smaller than Mars, gradually losing their atmosphere and water, with harsh seasonal extremes, where bacteria would naturally evolve durable cysts and become preadapted for surviving space travel on the stellar winds. A cyst moved by the solar wind and cushioned by the magnetosphere has a vanishingly small chance of reaching the Earth's atmosphere intact at a speed which would allow it to fall to Earth and live again, but billions of such cysts would make that event an inevitability and it only needed to happen once.

Fellow commentator 'derekcolman' asked me this...

Nice theory, but it begs the question, how did that bacterial life evolve on those other planets?

So I replied...

Aha ! Polypeptides show no replication ability in isolation, its not in their nature, whereas the sense-antisense structure of RNA makes it intrinsically capable of replicating its own polymeric sequences which may themselves have enzymatic capabilities as in the ribosomes today. So RNA is the best candidate for protolife. Amines alone cannot make life, but they can react with each other to make pyrimidines and these can make RNA like molecules in which circumstances RNA sequences might evolve to use amines in their environment and begin the process of evolution. This can happen anywhere the chemistry and energy balance is right, for long enough or in large enough quantities.

The question is why would one consider that more likely to have happened elsewhere. One reason is timing. "Other planets" existed long before the Earth did, so if living molecules can spontaneously arise at all, they were likely to arise there first. Judging from the estimated age of universe 13.75 bn years (assuming for now this isn't a Kelvinesque underestimate) compared to the estimated time it took for life to be established on Earth by whatever means ie approximately 1 bn years (and one can argue for a time period much less than this), the other planets had at least ten times as long to evolve life as Earth had so the probability is that at least one planet somewhere in the vicinity of Earth did based on time alone. But the chances of life beginning on other planets first are astronomically higher than the likelihood that life arose first on Earth, due to the enormity of the number of other planets.

The very large number of candidate planets implies a huge diversity of chemical environments. e.g. planets akin to warm Titans with massive amounts of hydrocarbons and ammonia and water on the surface with strong tidal heating to provide volcanic energy to compliment the light of its sun may have had ideal chemistry to act as an incubator for living molecules in the first generation of chemically diversified solar systems following the earliest supernovas long before the Earth existed.

The likelihood that life from one of these seeded the early Earth depends in part on how many life generating planets exist or have existed close enough to allow physical debris from them to have drifted to this solar system. Allowing for speeds with a magnitude in the range of the solar wind speed of 400km/s over 10bn years the upper range of over 13.3 million light years easily includes all of the local group of galaxies. Whether a bacterial cyst could stay viable for that long is another matter but that depends on the preadaptive evolution of the phenotype of the cyst and its travelling environment, which are highly variable factors. All known bacteria are adapted to the Earth environment and one cannot dismiss the possibility of seeding based on their vulnerabilies as a bacterium evolving on a dying planet would develope very different qualities more suited to space travel and lose them again once it arrived somewhere safer to live.

If one contends life evolved on Earth one has to accept it is more than likely that it evolved elsewhere first. The question is whether it can travel from there to here, between star systems and for the reasons given in my previous post I would consider it possible. What is wonderful about the Earth is that it has remained hospitable to life for so very long compared to its neighbours, due to plate tectonics and the constant tidal massage received from the moon in orbit which has (just barely) maintained an atmospheric balance sufficient to allow creatures like us to evolve who will one day carry life to other planets and whatever we evolve into will do so for as long as the universe will support life I am sure. So the Earth is a champ with great staying power and we owe it everything we have as well as our deepest respect for our own sake and the sake of life in the future, but it seems likely to me that it was given life from somewhere else even if NASA haven't dug anything up on Mars...yet!


Someone else mentioned Zecheria Sitchin as though he was a credible authority at which point I felt obliged to put a different perspective, while discussing the nature of the very early Earth just after the formation of the Moon...

That would not be my choice of reference for the impact theory.

Reginald Aldworth Daly (Harvard) proposed the impact hypothesis for lunar formation in 1946 and it was more widely discussed in scientific circles in 1974-5.

Sitchin began his pseudoscience publishing career in 1976 and like Von Daniken et al, simply incorporated elements of current progressive science into a mythical, mystical, cosmological mishmash to give his books superficial credibility and entertainment value in order to make money.

Nevertheless planetary collision has been widely accepted as a bonafide hypothesis which explains real observations of identical isotopic signatures for the Earth's and Moon's surface compositions. The only problem with it as a mechanism for the propagation of life (from one planet to another via collision) is the surface temperature of Earth after the collision. Pahlevan et al 2007 (CalTech) suggest that the collision was so energetic that in the aftermath there was an atmosphere of high temperature silicon vapour over a molten surface. This kind of temperature would vapourise any bacterial life no matter how hardy it had become and would have sterilised the Earth and Moon.

So it would not be possible for planetary collision to be a means for the propagation of viable organisms. This might only have occurred after the surface solidified and atmosphere cooled sufficiently to permit liquid water.

Wednesday, 2 March 2011

beginning the blog

I am a bit of a philosopher at heart, but then again, who isn't?


This blog space kindly provided by google is a place where I can at last publish a few ideas, after many years chewing them over, so others can think about them.


Please feel free to comment :o)