Australian paradox
Australia may provide an obvious test of Robert Lustig’s theory that sugar – and fructose in particular – fuels the obesity epidemic (24 September, p 35). We do not produce much corn, so we use cane sugar rather than high-fructose corn syrup for most sweetening.
In the 1960s Australia didn’t have an obesity epidemic. How much sugar did we consume? According to the , in 1965 it was 52.3 kilograms per person (out of a total sweetener consumption of 55 kg). Now, in the midst of our own obesity epidemic, we are down to 39.6 kg of cane sugar per person per year, with an additional 8 kg of non-sugar sweeteners. Despite a modest decline in consumption of all sugars, there has been a rise in obesity and diabetes.
How has our food supply changed over the past four decades? We eat more calories. It might be tempting to attribute the US obesity crisis to sugars, but the rise in obesity elsewhere demonstrates that more calories and less exercise are sufficient explanation.
Einstein's fate
Coverage of the speeding neutrinos (1 October, p 6) has led some to ask if Einstein got it wrong. Even if it is confirmed that these particles can go faster than light, the fate of Einstein’s relativity will almost certainly be similar to that of Newtonian theory – we shall continue using it happily where it does the job.
I could well believe it when I was told that NASA still relies heavily and unblushingly on Newtonian theory for its space calculations. All theories have their domains of validity within which their results hold good. The trick lies in knowing where the boundaries lie – an important function of experimentation.
Philosopher of science Karl Popper realised that experimental results could invalidate a theory, but seemed a little unsure about what action should be taken when that happens, possibly because the practical answer is very little. We simply avoid using the theory where we know we are outside its domain of validity, and tread softly where we are not sure.
Define violence
I hope Steven Pinker is right that the world is becoming a less violent place (15 October, p 30). That said, surely such an assessment must depend on what counts as violence. Adherents of some religions consider abortion to be violence, by which reckoning our society must be one of the more violent in history.
Similarly, the destruction of habitats and the extinction of species must also mark our time as distinctly violent.
C is for legend
Steve 91av’s influence will unquestionably be felt for many years to come (15 October, p 3). What has not been so widely reported is the death this month of Dennis MacAlistair Ritchie.
While not such a public figure, his impact was no less dramatic. As the creator of the C programming language and joint developer of the Unix operating system, he was a true legend who took computers from the academic realm and helped them become accessible to all.
I am sure Steve would have accepted that he stood on the shoulders of the likes of Dennis.
Hero or zero?
Much evidence has surfaced supporting Roland Huntford’s conclusion that Scott of the Antarctic “was consumed with hubris, which is what killed him” (1 October, p 30).
Not least is the tale uncovered by Don Aldridge in his book The Rescue Of Captain Scott. It reveals Scott’s unforgivable treatment of Harry McKay, a Scottish whaling skipper, famed “ice master” and explosives expert, who was sent in 1903 to free Scott’s ship Discovery from 18 miles of Antarctic ice.
Scott consigned the vastly more experienced McKay, along with William Colbeck, another competent captain who accompanied McKay, to oblivion and became a national hero in their stead.
From Rosemary Campbell
Huntford criticises various aspects of Scott’s expedition, including his decision to pull sledges on foot instead of on skis.
But if climatologist Susan Solomon, author of The Coldest March, is correct, Scott undertook lengthy preparations involving considerable research into all aspects of his journey to the South Pole, including pioneering efforts to predict the weather.
Huntford’s remarks about Scott “moaning about the snow” totally ignore Solomon’s account of research by the expedition’s meteorologist George Simpson into Antarctic weather, and his attempts to predict what Scott might face.
An unusually cold spell caught Scott’s party on their return across the Ross ice shelf, and contributed significantly to their failure.
Melbourne, Victoria, Australia
Sign 'em up
I admire Steven Newton’s commitment to open debate with young-Earth creationists in his comment on their attendance at Geological Society of America conferences (8 October, p 30).
But I worry that in the longer term they may want to get enough of their supporters involved so that they can elect candidates to the governing bodies of scientific organisations. It will be news to no one in the US that they are well organised and highly resourced.
One safeguard would be to ask all participants to sign a statement saying they accept that there is overwhelming evidence that Earth is over 4 billion years old.
This would challenge creationists and also give scientific societies a public relations tool. A similar statement could be drafted for evolution.
Limited thinking
Your article “Time’s arrow” (8 October, p 39) seemed tacitly to incorporate Immanuel Kant’s ideas on why time flows in one direction. Time, Kant argued, may flow in all sorts of directions, but we are forever blind to this because we can never think about time (or anything else) in any way other than one thought after another.
So our understanding of the nature of time, and everything else, is defined by the limits of what we can perceive and how we think.
Seminal seminar
Your article on metamorphosis (24 September, p 56) reminded me of a seminar I attended in the 1970s, on the reproduction of marine life forms.
A very large proportion of these organisms rely on the stable, oxygen-rich saline environment of the sea to nurture and disperse their eggs and sperm. What if things got mixed up – the “wrong” sperm finding the “wrong” egg? What would this lead to?
Help at hand
David Robson describes research into mind-body connections, including Matthew Botvinick’s discovery that a person can be tricked into believing a false hand is their own – the “rubber-hand illusion” (15 October, p 34).
He wonders about important clinical applications: “A version of the rubber-hand illusion might help the brain to accept a prosthetic limb.” My understanding is that a similar application exists. Conditions including phantom-limb pain have been successfully treated using a “virtual reality box”, more commonly known as a mirror box, invented by neuroscientist V. S. Ramachandran.
Describing his early results, Ramachandran observed that amputees sensed movement in the phantom limb, even though it was just a reflected image ().
He and his co-author commented that “there must be a great deal of back and forth interaction between vision and touch, so that the strictly modular, hierarchical model of the brain that is in vogue needs to be replaced with a more dynamic, interactive model”.
Spirited defence
In his letter, Quentin de la Bedoyere of the Catholic Herald makes the extraordinary statement that “science, by definition, has nothing to say about the spiritual aspects of humans” (15 October, p 33).
I am sure anthropologists and medical researchers would disagree. Science can look at questions such as: Do people with spiritual belief feel less or more pain? Do prayers make people heal faster or more completely? Are societies with higher or lower rates of spirituality happier, healthier or wealthier?
Science may not be able to confirm or refute some beliefs, but to say that it is, by definition, excluded from examining our spiritual side suggests the wrong definition is being used.
Gone to pot
I would add another idea to your list of alternatives to burial (13 August, p 44) – recycling your bones into pottery. It came to me when, on a visit to an old mill in Staffordshire, I was shown how animal bones had been ground up and burned to provide the reinforcement matrix in clay to be made into bone china.
Your bones could be used to make a keepsake for your descendants, or a special tea set, perhaps. On the other hand, if your will was not to their liking, a chamber pot might give them repeated satisfaction.
Vacuum tech
The smartphone would have been an even more impossible invention had Jeff Hecht tried making one using vacuum tubes (15 October, p 39). They were the only option when I started exploring electronics in around 1940. Even if it were possible to replicate a smartphone’s computing capability with them, an aeroplane hangar would have been needed to house them.
Hecht’s mention of personal computers reminded me of the first programmable desktop computer, the Olivetti Programma 101, which I used in the late 1960s. I was in good company – they were also used by NASA to plan the Apollo 11 moon landing.