Shedding a Kylie
After reading your articles about obesity and letters about units of measurements in Feedback, I now know I must lose a whole Kylie Minogue in the ongoing war against weight.
Leaky Bellamy
I am assuming that the “Hooray for global warming” letter is from the celebrated David Bellamy 鈥� the enthusiastic, beardy botanist and conservation expert 鈥� rather than some random pro-warming David Bellamy who recently bought some promising beachfront property in South Georgia (22 May, p 30).
In either case, the science of his argument is far from unequivocal. Large-scale studies of the effect of increased carbon dioxide levels on forest growth by William Schlesinger and colleagues at Duke University, North Carolina, showed an increase in growth rates for the first couple of years. But the growth of most plants in the study subsequently returned to the original rate, probably as a result of other factors taking over as the rate limiter.
Soil nutrients and water are not in endless supply, however many roots a plant puts down, so to take advantage of the increased growth rates offered by higher levels of carbon dioxide, the world’s “malnourished millions” will have to find plenty of extra fertiliser and water. So, unsurprisingly, no free lunch after all.
If well-known scientists are going to wade into such an important debate, studiously ignoring the enormous, non-botanical implications of global warming, their science should be utterly watertight. Bellamy’s is, at best, rather leaky.
No floods, no famine
As lead author of the report referred to in your article on glaciers in the Himalayas, I was shocked that the results of our three-year study could be so grossly misrepresented (8 May, p 7). As our report “An assessment of the potential impacts of deglaciation on the water resources of the Himalayas” concludes, the widespread perception that the region’s glaciers will disappear within 40 years is ill-founded.
In many areas, water shortages are unlikely to happen for many decades 鈥� if at all. Some areas may benefit from increased water availability in the medium term.
Catchments where glacial meltwater contributes significantly to the run-off, such as the upper Indus, appear to be most vulnerable to deglaciation. Eastern Himalayan catchments, benefiting from high summer monsoon precipitation, are less susceptible.
At no time did we suggest there would be a higher incidence of flooding, that famine would occur, or that an Indian government water-transfer scheme would be thrown “into disarray”. The individual quoted in the article, though a member of our study team, clearly presented his personal view of the situation.
Meaning of life
You say viruses are “as old as life itself, if not older” (8 May, p 16).
I thought that the definition of a virus was essentially that its genetic material relies on other organisms to reproduce. So how did these early viruses manage to pre-date life itself, before there was a convenient organism to hijack in order to reproduce?
The editor writes:
鈥� It all depends on what you mean by “life”. Viruses could have piggybacked on even the incomplete metabolisms of pre-cellular, er, life.
Nature's poisons
Chris Richardson remarks that “treatments of natural origin might not be 100 per cent safe” (15 May, p 28). Indeed so, and it prompts the question of why substances of plant origin should have any physiological effect on animals at all.
The obvious answer is that plants have evolved these substances to poison animals that would otherwise eat them. The “natural” effect of any herbal product is to make the user sick. If small quantities produce a beneficial physiological effect in some circumstances this is an accidental advantage to us. So it is not surprising that many touted remedies, such as ephedra, St John’s wort and comfrey, turn out to have harmful effects.
On the other hand, pharmaceutical companies intend their products to do us good, and spend enormous sums developing and testing them to reduce the risk. Also, they try to find out in advance the effect of taking them at the same time as other drugs, and their effects on special categories of patient: people with diabetes, a compromised immune system, reduced liver, kidney or thyroid function, and pregnant women. Few proponents of “natural” remedies (or perhaps that should be natural “remedies”) can give this information. The only “100 per cent safe” remedies are homeopathic ones. They never have side effects.
Unhappy heydays
I was amused to see the following strange comment appear in your article on the threatened bird of paradise (15 May, p 46): “Their heyday was in the late 19th and early 20th centuries when thousands of the birds were slaughtered and their plumes shipped west on the new tea clippers, destined to decorate the hats of Victorian ladies.”
Presumably the heyday of the American bison arrived with the railway, and that of the cod with their rise to popularity in fish and chip shops across the UK.
That's the limit
You report on new calculations of a fundamental limit to computing power (8 May, p 12). Back in 1962, Hans Bremmermann derived a more absolute limit, based on the fundamental coarseness of space-time. He calculated a limit of no more than 1.6 脳 1047 bits per gram per second.
As Ross Ashby pointed out in the 1966 paper “Modeling the brain”, which alerted me to Bremmermann’s work, whether the gram of matter is in the most advanced type of computer or inside someone’s skull is irrelevant.
Spiral growth
Your item on cactus growth patterns states that the reason why plants follow a precise mathematical sequence (the Fibonacci series) “has always been a mystery. Now the problem has been solved” (8 May, p 12).
In fact Peter Stevens, in his book Patterns in Nature, explained back in 1974 that many plants have spiral arrangements which develop in a Fibonacci series. But as Stevens says, plants have no knowledge of mathematics: they simply grow their stalks where they have the most room. This must, and can only, produce a Fibonacci series, and it is the full and elegant explanation of how the Fibonacci series arises.
In fact, a growth pattern that reduces the mechanical stress is clearly that which arises from plants growing where they have most room to do so. Your correspondent is expressing the same thing in different words.
Melanesian Vikings
Far from having to suppose any need on the part of Polynesians to take on Melanesian navigators (24 April, p 38), the differing male and female chromosomes of the Maoris can be readily explained if the Melanesians played the same role in the South Pacific as the Viking and Saracens did in the northern hemisphere.
If they pursued the familiar career of raiding coastal settlements in New Zealand or in the islands that the Maoris’ ancestors later emigrated from, then in cases where they were successful they will have slaughtered the men and boys and raped the women. They then either left or settled down in their newly conquered areas, holding the captured females as slaves to be the mothers of the next generation.
In either case, continuous predations of this sort over centuries would ensure the preservation of Polynesian mitochondrial DNA in the female line and gradually insert Melanesian DNA into the male line, while the offspring would have adopted the same language as their mothers. Small wonder then that the Maoris fled even to remote Enderby Island, just as numerous Angles and Saxons fled across the water to escape the predations of Attila and his Huns, or numerous Britons fled across the water to Brittany to escape those of the Angles and Saxons.
Ball with a view
Your Invention column describes a patent for marking a ball with a pattern of 55 dots in five colours, which will present a unique appearance at every possible angle (8 May, p 23). This sounded unnecessarily complex to me, so I pulled out an orange and marked the surface into eight “triangular” sections, or octants. I then painted it red, yellow, green and blue.
It doesn’t matter which way you turn this ball, you always get a unique view. Am I missing something important about that bespeckled ball mentioned in your column? Or should I be contacting a patent attorney, since my ball apparently does what theirs does, and it is much prettier (see ).
The editor writes:
鈥� To be fair to the inventors, they do say in their long and complicated patent that solutions with fewer markings are possible and the invention also applies to non-spherical balls with irregular shapes.
Abstract granny
I was glad to see your article about Biopresence (15 May, p 17). Our project aims to create permanent memorials to deceased loved ones by infusing their “genetic essence” into apple tree genomes.
Your article questioned the link between the person and the tree. The altered apple gene sequence represents human DNA insofar as it is possible to decode the apple gene sequence and retrieve the original human DNA sequence. We are aware that some people might have a problem with this mapping aspect. Human DNA itself is already an abstract representation of a human. Introducing yet another abstraction layer does not change this concept at all, in our opinion.
What we are interested in is attaching meaning and memory. The tree will still be a tree, but if it encodes my DNA, it will have greater emotional and physical significance to me than the contents of your average wood, glen or garden centre.
Isle be there
I was leafing through an atlas, looking for an up-to-date version of the Carta Marina map (8 May, p 6). I noticed that the map conforms quite closely to a Bonne projection whose centre is in the Middle East (well outside the area shown). But the oddity is an island called Tile somewhere between the Orkneys and Iceland, which appears to have sunk since 1539.
The real Dr Strangelove
In his review of Edward Teller: The real Dr Strangelove, Frank Barnaby suggests that Dr Strangelove may have been based on Henry Kissinger (15 May, p 48). The film was made in 1964. Kissinger only became National Security Advisor in 1969 and Secretary of State in 1973. In 1964 he was a relatively obscure faculty member at Harvard. It’s highly unlikely that Stanley Kubrick or Peter Sellers would have based Dr Strangelove on an almost unknown academic.
As for Edward Teller, he was Hungarian and fled his country to escape the Nazis. Strangelove was German and had a mechanical arm with a marked tendency to spring into “Sieg Heil” salutes. It is true that in his later years Teller was confined to a wheelchair, but not in 1964.
More likely candidates are Wernher von Braun or, as Barnaby mentions, Herman Kahn. However, neither of them is mentioned very much nowadays. Currently Teller and Kissinger are seen as having been of greater significance, and this present view seems to have distorted memories of circumstances when the film was actually made.
It’s likely that Strangelove is a blend of characteristics from different sources rather than a parody of an individual.