Cooking immunity
Researchers into acrylamide seem to have missed a crucial point (22 April, p 8). Yes, possibly it is toxic to cows and rats, but why should it also be toxic to humans? Unlike these animals, we have been eating cooked food for at least a million years. Isn’t it reasonable to suppose that, if we had not evolved some sort of immunity (a genetic mutation perhaps?) to any harmful effects, there would not be so many of us now?
'Commercial' cull
The fact is that for millions of years seals and cod (and all the other species in the north-west Atlantic) lived in balance and the cod were present in great abundance. It was commercial overfishing that led to the collapse of the cod population in 1992, and it ill behoves us to continue to blame the harp seals as Wesley Ludemann does (22 April, p 20), particularly (and ironically) as a healthy harp seal population may even help the recovery of the Atlantic cod by preying on its rival, the (non-commercial) Arctic cod.
The Canadian harp seal hunt is, quite simply, the largest and most brutal slaughter of marine mammals on Earth and should be seen for what it really is 鈥� an unnecessary commercial hunt 鈥� and not excused for bogus, quasi-scientific reasons.
Ludemann also refers to the “doubling” of the harp seal population during the “last seal-hunting ban”. In fact, the population had already been reduced by two-thirds by the excessive levels of seal slaughter 鈥� the same levels we are seeing again today.
From Peter Wright
Wesley Ludeman suggests that the Canadian harp seal cull is justified as a protection measure for cod stocks. Unfortunately things are not that simple. Merely demonstrating that seals eat cod is not sufficient to justify a cull, since most non-human predation on young cod is probably carried out by other fish species. In the crudest possible terms, if the predatory fish eaten by seals would have eaten more cod than the seals do, culling seal populations would reduce the cod stock.
Before you could justify a cull on these terms you would have to carry out a qualitative study of all feeding interactions affecting all stages of the cod’s life cycle. Given that Canada undoubtedly has the resources and expertise to carry out such research, the absence of fisheries officials waving food web analyses probably speaks for itself.
Polegate, East Sussex, UK
Nuclear expertise
In your article on the future of nuclear power, you correctly quote my rather pessimistic view of the UK’s inability to build new nuclear power stations, even though we may need them in the future (22 April, p 33).
We are in this pickle because successive governments have paid no attention to the scientists and engineers who have to actually make things happen. The Royal Society reported in 2000 that a decision would have to be made about nuclear power by 2002 at the latest. By constantly putting off that decision, the government has jeopardised both the security of our energy supply and our carbon dioxide emissions targets.
However Electricit茅 de France, a major supplier of electricity in the UK, has offered to fund and build 10 nuclear power stations in the UK. No doubt we will pick up some work as sub-contractors, but EDF will need government assurances that it will provide a long-term, stable energy policy. EDF will not be looking for subsidy, but if it were given the same encouragement that renewable energy enjoys for producing carbon-free energy (拢6.5 billion in total by 2010) that would be a bonus.
Home planet fossils
In the quest for ancient rocks that may contain biological material, need we go as far as the moon, as Peter Ward suggests (1 April, p 38)? It would be cheaper, and it might be profitable, to examine closely the dropstones found in the Earth’s most ancient tillites (glacial deposits). These stones may be unique in that all other contemporary rocks have probably been eroded or subducted since they fell from their glaciers 鈥� and as they were certainly at or near the Earth’s surface when the ice picked them up, some of them are likely to be of sedimentary origin and to contain microfossils or material derived from them.
Confusing definitions
Following your article on the promise of synthetic wheats produced without genetic engineering (11 February, p 8), I made the point that strictly speaking, the wheats should qualify as genetically modified organisms if the EU’s definition of a GMO is strictly applied (11 March, p 22). The aim of my letter was to expose stark inconsistencies in the way that the EU legally distinguishes GM plants 鈥� which are subject to strict regulation 鈥� from “conventionally bred” plants, which escape similar scrutiny.
In your 1 April issue (p 24), Edo Lin countered that the wheats don’t fall under the GMO definition because EU legislation explicitly exempts plants bred in the same way as the synthetic wheats. The method relies on a chemical that tricks wheat plants into doubling their chromosomes, enabling them to breed in a way that would not be possible naturally.
Lin is correct that plants bred in this way are exempt from the GMO definition, as are plants produced through other “conventional” methods such as deliberate mutation of chromosomal DNA to produce plant variants not found in nature. Yet these and other methods exempted by the EU legislation on GMOs can introduce changes in plant DNA and plant structure vastly eclipsing those introduced by genetic engineering itself, as defined by the EU. Ironically, the definition as it stands may discourage newer, safer ways of altering plants by silencing unwanted genes with tiny gene-specific fragments of RNA. My point is that the EU’s legal definitions of GMOs are way out of step with what actually happens biologically and genetically in plants, and need radical reappraisal.
If anything, Lin’s response reinforces my argument, that definitions from Brussels rely more on semantics than scientific precision, a situation which may be politically expedient but which is scientifically dishonest and confusing for European consumers.
First quake expert
The geologist cited in Jessica Marshall’s story says that the San Francisco quake of 1906 triggered “the beginning of earthquake science” (15 April, p 8). But historians say that the father of modern seismology was an Englishman, John Milne, who was enticed to Japan in 1875 by the Emperor Meiji. He became a professor at Tokyo’s Imperial College of Engineering, which was then the largest technical college in the world, and founded the Seismological Society of Japan, the first of its kind.
Having assembled the largest group of earthquake investigators anywhere, Milne ran the first coordinated quake investigation after a huge quake struck central Japan in 1891. So this is one scientific birth that my fellow Americans should not be so quick to claim.
Selective memory
Robert Matthews reports speculation that “epitaxy” and “succussion” ought to trigger greater scientific interest in homeopathy (8 April, p 32). However, homeopaths rely on far more extensive claims than the already controversial one that water might somehow generate an atomic template of substances that pass through it.
For one thing, they claim that water selectively “remembers” the very substance that the homeopath wants it to remember. Now, if it remembers a tiny trace of arnica, say, why does it not also remember the silicates out of which the bottle was made, or the rubber from the dropper, or the dust that no doubt wafted in during the processing of the remedy, all of which will also have been succussed. Why does it not also remember its entire history all the way back to when it was contained in some dinosaur’s bladder?
Periodic baptisms
Regarding the ongoing saga about souls and egg fertilisation (8 April, p 24): as a good Catholic child I was instructed that, upon coming across a dead or dying baby in the street, I had not only the power but the duty to baptise that baby myself, because if I failed to do so then its soul would not be able to go to heaven.
Now, years later, having learned about the beginnings of life at fertilisation and how fertilised eggs sometimes fail to attach themselves to the wall of the womb, I am surprised that I was not advised to carry out a monthly baptism on my sanitary towels. Another problem for the Pope.
For the record
鈥� The feature on gene copy number variations (“Magic numbers”, 8 April, p 38) did not make it clear that such variations are responsible for only the most common form of Charcot-Marie-Tooth Syndrome, called Type 1A, which accounts for roughly half of all cases. Other forms are caused by mutations in genes rather than variation in gene copy number.
鈥� In the feature “Newton’s Curse” (8 April, p 47), chemist Cathrine Reck’s name was misspelled as Catherine.
鈥� Our apologies to Christine Brooks, who sent in the Feedback story about a giant squid at the London Natural History Museum (Feedback, 6 May). We only noticed the email header “Chris Brooks”, and erroneously assumed her to be male.
Gas guzzler adverts
Ross Russel laments the presence of gas-guzzling luxury car ads in a scientific publication, mistaking New 杏吧原创 for Green Left Weekly (8 April, p 24). Perhaps he neglects to mention that the average income of scientists is higher than plumbers or unemployed hippies, which is what attracted Saab, Mercedes, and Peugeot with its HDi eco-friendly luxury cars to advertise in this publication. Surely well-to-do scientists can be harangued into making such corporate choices worthless by not buying these cars, and the magazine can get by on whatever revenue it can drum up.
From Alexander Croll
What nobody seems to realise is that SUVs, MPVs and other “gas guzzlers” can constitute a better choice for the environment than “green” cars. I make this assertion based on my own experience.
We are a typical family. We do not live in a large urban centre, and our local public transport links, while good, are neither as extensive nor as convenient as those which seem to be taken for granted in the high-density population centres where it seems many lobbyists are located. We used to use two smaller cars, a Citroen ZX and a Vauxhall Astra, which generated approximately 190 grams per kilometre and 230 g/km of CO2 respectively. We now rely upon one Honda CR-V, an MPV that generates around 315 g/km.
I can already hear the indrawn breaths, hisses and cries of horror from proponents of the small-is-green stance. But consider the big picture: we use the MPV somewhat less readily than we used the individual cars. Not only do we perceive the MPV as being more expensive to run, but we tend to defer non-essential journeys in case other members of the family need the car. By making fewer journeys, and with more of them multi-stop than before, our total distance travelled by car in any given month has fallen. Consequently our monthly carbon emission is around 396 kg per month for the “gas guzzling” MPV, compared with 425 kg per month when using the two smaller cars. I accept that this is not a massive decrease, but it is far from the catastrophic increases cited by those who hate SUVs, MPVs and the like, seemingly on principle.
Camberley, Surrey, UK
From Chris Gibson
Apart from my mother-in-law, all the New 杏吧原创 readers I know work in the oil and gas industry. Perhaps the ad men have got it spot-on by targeting readers with a vested interest in oil consumption?
I also like the occasional malt whisky and use a digicam.
Washington, Tyne and Wear, UK
Cops can save forests
If, as William Laurance suggests, 80 per cent of Brazilian Amazonia logging is illegal (15 April, p 24), wouldn’t the most cost-effective way of counteracting global warming be to bolster Brazil’s law enforcement, as, I gather, has been done successfully in Mato Grosso State?
DVD protection
Digital Rights Management is the discouraging effects of cinemas’ sticky floors, rancid popcorn, blurred projection and cramped chairs recreated in the comfort of your own DVD player. Because if you want to watch your movie anywhere except on the single TV in your living room on which you are licensed to, you can’t. If the disc is poorly encoded, you cannot re-encode it to fix it. If you want to lend it, physically, to a friend, even to encourage them to buy it, you won’t be able to. This does not add value to consumers’ experience of movies.
What it does is makes movies on DVD less worthwhile. How this will make more money for “artists” (who do not run the movie companies that mandate DRM) is something that Charles Gillingham of Counting Crows doesn’t explain (15 April, p 26).
Kalulu the lunar hare
Edmund Weiner ended his letter by mentioning that “according to some eastern cultures it’s a rabbit” in the moon (4 March, p 25). All over Africa the rabbit in the moon is actually Kalulu the Hare.
As a child in Zambia I grew up to believe folklore that Kalulu was banished to the moon because of all the wily tricks he pulled on other African animals, especially Lion. There are many stories told round the campfire, when the moon is full, of Kalulu’s clever tricks.
Flu virus missing?
In response to the article claiming the UK’s bird tests may be missing the avian flu virus, I would like to say that the British testing programme is intended to detect the incursion of H5N1 into the UK via wild bird populations (15 April, p 12). This is based upon the detection of viral nucleic acid using the polymerase chain reaction (PCR). Bj枚rn Olsen refers to surveillance for the “virus” itself in his programme surveying healthy wild birds. The survival of infectious virus may well be enhanced in aqueous solution but our laboratory testing is based upon the detection of viral RNA that is present even when infectious virus does not survive.
Studies are in progress to produce validated data on virus survival in different media, but unpublished data from experimental studies here at the Veterinary Laboratories Agency indicate good viability of viral RNA on dried swabs stored at 4 掳C. Placing faecal material into aqueous solution may be detrimental to the stability of the RNA if the pH is not buffered to neutral values. The procedures used conform to international protocols endorsed by the European Union’s wild bird surveillance programme.
We have not seen the validation data relating to the method used by Olsen but direct comparisons between “dried swabs” and the use of transport medium will be important. The survival properties of viruses in different environments and media are currently being studied at the VLA, and part of this will be stability of virus from faeces.
From Graeme Laver
The survey you reported seems to have isolated fewer than expected avian influenza viruses from wild birds in the UK, and the way the samples were collected and stored could be to blame. On one of our trips to the Great Barrier Reef in the 1970s we collected 642 cloacal swabs from healthy shearwaters and terns, from which we isolated nine low-pathogenicity influenza viruses. Other surveys seem to have had a similar isolation rate.
We used dry swabs to collect the samples from the birds’ cloacas. These were immediately put into tubes containing 2 millilitres of tissue culture growth medium and then snap frozen in liquid nitrogen. The samples were never allowed to dry out or stored at the temperature of a domestic freezer, which would have destroyed the virus, for sure.
Nowadays, cloacal samples are tested for virus using PCR to amplify RNA, so virus in the samples does not have to be kept “alive” unless viable virus is required for further experiments. If liquid nitrogen is not easily available, cloacal swabs for PCR can be put straight into ethanol, which destroys the virus but preserves the RNA.
I don’t know if the refrigerated swabs that had dried out (as reported in your article) were still suitable for PCR analysis, but I suspect from the results that they were not. But why on earth do this? Putting the samples into ethanol is no big deal.
Murrumbateman, New South Wales, Australia
Debora MacKenzie writes:
鈥� We asked the UK’s Department for Environment, Food and Rural Affairs, which runs the VLA, whether it would evaluate different methods for preserving bird flu virus in field samples. DEFRA said it is “looking into the possibility of conducting a trial in this area”.