Oeufs Boltzmann
Can someone tell me what is the opposite of a Boltzmann brain (29 March, p 46)? It seems to be a self-reproducing brain that arises through a copy-construction process, not spontaneously from thermal noise. But the complexity of a zygote is many orders of magnitude lower than that of a brain. So random thermal noise will far sooner produce “Boltzmann zygotes”, as unlike ours as you may care to imagine.
In a suitable environment these will not only grow into brain-containing organisms, but may breed species that may go on to colonise whole galaxies, and inevitably in the fullness of time invade our own 鈥� leaving us not only atypical but extinct.
For the record
鈥� We stated that there have probably been fewer than 25,000 generations since the human lineage split from that of chimpanzees (19 April, p 30). As several readers have spotted, there was a missing zero: it should have said 250,000.
鈥� In the graph accompanying our evolution special (19 April, p 33), the red line in the top graph should not have been there. We should also have stated that the simulation models diploid individuals. This is why, in the population of 10, the fraction of the population with a particular mutation varies in steps of 0.05 rather than 0.1.
Genetic widget-chucking
Thank you for the balanced debate on the important issue of “feeding the world” (15 March, p 5). It will probably elicit the old objections that those opposed to genetically modified crops are “anti-science”. This was always an unfair response. We have long been missing a critical discussion of what the technical potential of GM for improving crop yields really is.
Rather than resembling real engineering, genetic modification is more like trying to improve a well-designed sports car by randomly throwing interesting widgets into the works. This was never a sensible approach.
Crop yields are only the result of overall improvements in the performance of the plant, with many contributing genes and factors. On this basis alone, any ability to increase yields through individual genes was inevitably limited and uncertain.
On top of this, all the inherent side effects of the GM process make the outcome far too unreliable. The random insertion of new genes disrupts existing genes 鈥� some physically, many biochemically 鈥� and diverts energy and nutrients from the existing plant functions. These technical problems (and many others) mean that nearly all attempts fail. Even if after years of persistence and a dose of luck a GM variety that seems good enough is produced, one at least good enough to market, the full impacts are not evident until long commercial use in a range of conditions gradually reveals which of the plant “secondary metabolite” functions have been affected and what impacts this has had on average yields or health.
Also, once a GM variety has been developed, you have to start over again on other crops and additional characteristics to make any further progress.
In contrast, it is well recognised by agronomists that the gains you can achieve though better crop management are substantial. By applying techniques that harness natural processes to intensify the supply of soil nutrients and other resources 鈥� the approach of organic and other “agro-ecological” techniques 鈥� multiple gains are achieved (for yield increases, drought resistance, crop and nutritional diversity, income gains, etc) and for several crops at the same time. This is why, hard though it is for Syngenta to accept, the debate has moved on from GM crops. Nevertheless, please be assured that this approach is still scientific, though it is based on ecology and biology rather than chemistry and genetics, the disciplines behind agrochemical and GM approaches.
Down on the farm
I am gratified that Deborah Keith thinks that the plant science industry cares passionately about abating hunger and supporting rural development (5 April, p 17). But development into what? Towards a situation where even small, Third World farmers who have been growing traditional crops developed over generations to suit local conditions are forced to grow patented GM crops with terminator genes, and so have to buy their seeds from the agro industry every year? Thousands of farmers in India have committed suicide after finding themselves in debt to such companies.
The huge investments required may justify intellectual property protection, but whatever the reason it is another powerful tool for gaining complete control over the activities of the farmers.
Obviously, it is for the benefit of the shareholders who prosper as the money flows out of the Third World and into the bank accounts of investors in the developed world.
In regard to sustainable farming, trying to produce a monoculture over huge acreages organically may indeed require more land. But producing organic crops on small mixed farms where owner-operators do the work and sell locally is far more beneficial for society. The profits remain in the community where the farmers live.
Of course, small organic farms are not going to provide the control or income for the agro-industry giants.
In the same issue, the article “The End of civilisation” (p 32) describes research that shows a complex society that relies on a few huge systems to supply its necessities is very vulnerable to catastrophic failure. It points to the problems inherent in imposing more and more layers of technology on a system in order to solve problems, instead of addressing their root cause. Dare I mention that the cause of humanity running out of food is that there are at least twice as many human beings on the planet as it can sustainably support?
Vote for negativity
I was interested by Phil McKenna’s description of the problems of voting systems (12 April, p 30), but disappointed that the suggested alternatives did not allow the electorate to do what I propose they really want: to vote against a candidate.
Talking to people about their voting intentions always brings up the worry that voting for any candidate other than one of the two dominant parties risks letting the undesirable party in by splitting the vote. This is easily overcome by giving each elector two votes 鈥� one for a candidate, and one against another. The outcome is decided by the totals for each candidate.
A likely consequence would be greater numbers of able independent representatives. I would rather have hundreds of minds considering each piece of legislation. It would also be salutary for major parties to have their candidates getting negative totals.
Television programmes in the “reality” genre have demonstrated public interest in voting out the unpopular. Perhaps the chance to do this for legislatures would increase the number of citizens actually using their votes.
ID crisis
I would be interested to know whether John Denham still believes that the UK government 鈥� of which he is a member 鈥� can deliver “a properly organised identity card system, as long as it’s properly structured, as long as the data is held in the right way and so on” (5 April, p 44).
He uses the phrase “absolutely secure system”. To anyone who has worked with databases or information security, this is as crazy as British politicians’ statements that beef was “perfectly safe” at the time BSE was taking hold among the country’s cattle.
I am glad Denham knows about false positives and false negatives. When I asked the UK Identity and Passport Service what rates of false positives and false negatives were specified in the design objective of the ID card scheme, they did not answer. They were also unable to quantify how effective ID cards would be in counter-terrorism compared with, say, better intelligence or more security officers. Perhaps Denham could?
I am in favour of a robust range of identity verification, not dependent on a single scheme, organisation, technology or authority. There will be risks, of course, but fewer than in the “One Ring” approach of the ID card plus the National Identity Register. I would prefer an ID scheme of limited scope managed by the banks, for example, because I trust them a little bit more than the government to secure the data and restrict its propagation.
Nuclear future
Your editorial on forgetting the nuclear past (12 April, p 5) mentions as the worst nuclear accident in US history the one at Three Mile Island, Pennsylvania, in 1979. I was about 150 kilometres to the north at Penn State University at the time, but that one didn’t bother me.
What did was the much worse near-meltdown of the Enrico Fermi sodium-cooled fast breeder plant outside Detroit, Michigan, in 1966. An engineer is reputed to have said: “We almost lost Detroit”.
From John Jones
Rob Edwards makes exaggerated claims about the risks of nuclear “super-fuel” (12 April, p 8) which, as a safety analysis engineer at closely involved with these issues, I must dispute.
He claims: “Since 1970, the average burn-up of these reactors worldwide has almost doubled, to more than 40 gigawatt-days per tonne of uranium (GWd/tU). The next generation of nuclear reactor plants will bring a further step change.” In reality, average burn-up in excess of 65 GWD/tU is routine in European countries, using the same fuel design as used in the UK at the Sizewell B plant in Suffolk. To the best of my knowledge, new nuclear reactors are not planned to exceed this.
Edwards claims: “Fuels operating at 60 GWd/tU would produce around 40 per cent more hydrogen than existing high burn-up fuels.” Hydrogen being absorbed during corrosion of fuel cladding is only an issue for cladding alloys developed in the 1970s. Modern alloys take up negligible amounts of hydrogen in normal operation.
Finally, he claims: “Fuel with a burn-up of 55 GWd/tU irradiated in a pressurised water reactor would be around 50 per cent more radioactive than low burn-up fuel of 33 GWd/tU throughout the time it needs to be stored.”
In the short term, the heat generation is actually reduced. A month after discharge the difference in heat generation is only a few per cent. There may be large differences after a very long period of time, but by then the heat loads will be much less.
Churchdown, Gloucestershire, UK
Kitchen carbon sink
It seems odd to try to come up with weird and wonderful methods to “pull” carbon dioxide out of the atmosphere (29 March, p 36, for example). We already have extremely efficient, tried and tested, solar-powered devices that can easily be produced in large numbers with little investment.
They are called plants, and probably the most practical form of this “device” would be single-celled algae which, with a bit of common-sense engineering, can easily be manipulated and farmed. The only by-product would be large quantities of hydrocarbons. Now, if only we could think of a use for these…
Value of nothing
You refer to the “ecosystem services” of rainforests as having “a commercial value of zero” (5 April, p 5). I understand that we derive about half our drugs and medicines from the gene pool of the world’s flora and fauna, but that we have researched only about one-tenth of the species in the ecosystems of rainforests, in which about 80 per cent of the entire gene pool exists.
It seems that far from being of zero commercial value, this is of potentially great value, and further reason to protect forests.
The editor writes:
鈥� We were referring to the practice 鈥� common to many economists, including Karl Marx 鈥� of assigning a value of zero to natural resources.
Down on the farm
I can accept that Deborah Keith did, as she says, choose a career in crop science in order to combat world hunger (5 April, p 17). But the managers of the company she works for have only one goal: to maximise profits. To claim it is guided by a philanthropic mission statement is at best misleading.
This is no slur on that company, but a simple reflection of the way any commercial company has to operate under the current system. Its stock price depends on whether investors think they will get a good return on their money, not on whether it is helping the developing world. To keep shouting that you’ve got to recoup your investment is pretty pointless when your potential customers simply haven’t got the money.
It would be wise for the agribiotech industry to engage in negotiations that acknowledge the complexity of farming issues by bringing together different disciplines and viewpoints. These offer the only road that can possibly lead to a solution that recognises the needs of both the poor and the multinationals, thus unlocking this immense potential market.
Cuba libre
Your feature on the health benefits of calorie reduction in Cuba after the collapse of the Soviet bloc (12 April, p 6) fails to consider a key variable. The Cuban food supply, as well as being restricted, also became organic.
You have reported a link between type 2 diabetes and pesticide residues in food (14 April 2007, p 16). Has the possibility been considered that the 51 per cent reduction in diabetes might be due, in part at least, to the absence of pesticide residues?
Stick to the laws
Scientism has come to signify the view that only those fields of inquiry that employ the methods and explanatory styles of the natural sciences count as generating genuine knowledge and genuine explanations (12 April, p 48). This is absurd because it would imply that most ordinary, everyday and quite proper claims to knowledge and explanation fail to be such.
Confusion frequently arises, especially in debates about religion, because people fail to distinguish between scientism and naturalism, especially methodological naturalism.
The version of the latter I favour is the methodological principle of seeking explanations for occurrences 鈥� of any kind 鈥� that are consistent with known laws of nature. This places a constraint on permissible kinds of explanation while allowing for forms which, though consistent with natural science, are not of the natural science kind 鈥� such as can be found in everyday life, detective stories, history and so on.
Opting for methodological naturalism while rejecting scientism offers atheists quite a generous intellectual base. This is a good thing because it is the flirtation with scientism of some well-known atheists that makes them often seem narrow-minded and bigoted. If the two are not distinguished, a legitimate attack on what is really scientism can be presented misleadingly as a seemingly more serious attack on naturalism.
Evolution in action
One key sentence in your evolution special (19 April, p 24) gave me cause for concern. Michael Le Page wrote: “The success of western civilisation is based on science and technology, on understanding and manipulating the world.”
There is plenty of evidence that this endeavour is failing. We are now all aware that western civilisation is almost certainly driving climate change, and that for some time we have been manipulating the world without really understanding it.
In 2001, over 1000 scientists signed the , which states: “The Earth system behaves as a single, self-regulating system comprised of physical, chemical, biological and human elements.” This sounds less like something to be manipulated than something to work in concert with.
From Andrew Cherry
I am a scientist and a Christian. I don’t believe that it’s God’s hand on my head that keeps my feet on the ground. Similarly, if an omnipotent god can create the physical universe with all its laws, then that same god is certainly capable of creating evolution and natural selection as a mechanism for species development.
Marrickville, New South Wales, Australia
From Rob King
Michael Le Page, in his otherwise excellent article dispelling misunderstandings about evolution, perpetuates another, saying that “evolutionary psychology is notorious for attempting to explain every aspect of human behaviour… as an adaptation”. This goes back to the late lamented Stephen Jay Gould’s blind spot about admitting that humans could have a nature.
Evolutionary psychologists do develop hypotheses through a reverse-engineering stance, looking at what current behaviours might have solved as adaptive problems in past environments, but only the insane would believe that every one of the vast numbers of overlapping behaviours is an adaptation.
In any case, it does not matter where I get my hypotheses from: the mathematician Srinivasa Ramanujan prayed; the physicist Albert Einstein found them in dreams; and a colleague swears he has a psychic Platonist cat who sends him messages. What matters is the testing.
London, UK
From Clarence Ransom
Your rebuttal of the proposition “It doesn’t matter if people don’t grasp evolution” has a bearing on a major problem in Texas.
If some Texans had their way, creationism would have to be included in Texas-designed textbooks 鈥� which many other states buy. Those people claim they want equal time for alternative theories, but what they want is to force all teachers to teach creationism and to ignore evolution.
Colleyville, Texas, US