Letters archive

The loss aversion that dogs our ability to deal with climate change as George Marshall describes (16 August, p 24) is documented by Dan Ariely in the book Predictably Irrational . Ariely shows that students who are given free rein over when to submit work generally do worse than those given deadlines spaced throughout the …

Daniel Kahneman's research into people's aversion to the facts on climate change, quoted in Marshall's article, sets the tone for much of the debate that occurs around this topic. Marshall distils it to "sacrifice now for benefit later". This indicates a type of bias that affects much research in sociology and medicine, where we only …

Michael Le Page tells how all life on Earth derives from LUCA, the last universal common ancestor (16 August, p 30) . It seems odd that life originated only once. Why has a different biochemistry not begun to evolve in parallel during all these billions of years? Was the emergence of prokaryotic and then eukaryotic …

• There has been a lot of speculation about this. LUCA is widely thought to have been the amalgamation of various proto-biochemistries, and most researchers are open to the idea of a "second genesis" – multiple independent origins of life that were outcompeted by life as we know it. And many researchers think other biochemistries …

Helen Thomson writes that transfusions of young blood may help treat age-related conditions such as Alzheimer's and heart disease (23 August, p 8) . Given that there are about 2 million blood transfusions in the UK every year, and that the blood services and hospitals keep detailed records, could the research benefit by analysis of …

• There is a lot of blood swapping going on, but the benefits of young blood are likely to be transient, making any effect difficult to measure retrospectively. In addition, uncovering the age of existing donors may be difficult.

Stephen Ornes's article about rogue waves suggested that up to half of these waves result from "crossing seas" in which wave trains from different directions interact (26 July, p 42) . In the early 1980s, my research student Chris Machen conducted experiments in a wave tank at Newcastle University capable of generating crossing waves. The …

In your article on rogue waves, I was astonished there was no mention that negative peaks exist as well as positive ones. Such rare, huge troughs might be more dangerous than waves of similar magnitude and would be more difficult to spot from the deck of a vessel. This might explain the lack of observation …

George Wadsworth makes very valid points about the need to use all alternatives to generate electricity for the world's poorest people (23 August, p 28) . These alternatives need to be maintainable by those communities or they will eventually fall into disrepair and discredit future efforts. Remote villages may have no skilled technicians able to …

As well as tackling autoimmune disorders such as type 1 diabetes (23 August, p 26) , consciously raising the activity of your sympathetic nervous system could be used to combat obesity. Since 2009, there has been renewed interest in the possibility of stimulating brown adipose tissue to burn fat. Repeated exposure to cold – used …

Congratulations to Jon White for an excellent article examining the mixed health benefits of saturated fat (2 August, p 32) . However he seems to have missed a further meta-analysis. It was noted that Japanese people on a low-fat diet experienced a low incidence of heart disease, as did the French who enjoyed a high-fat …

You report on the growing number of people from the UK, especially those with neurological diseases, going to clinics in Switzerland to end their lives (23 August, p 7) . One reason might be that many people worry they will have a painful, undignified death. Some relatives remain traumatised after seeing their dying husband or …

I am not sure whether I am more surprised by Guy Cox's revelation that you needed to submit to the distinctly un-Greek custom of circumcision to be admitted to the library of Alexandria, founded around 280 BC, than I am to read that it applied to Pythagoras, who passed away some 200 years earlier (9 …

Anil Ananthaswamy describes a thought experiment in which three electrons behave as if they were linked in some way, without their having been entangled artificially (2 August, p 8) . This experiment has not yet been performed, but remote correlations between non-entangled photons were demonstrated in 1956 by Robert Hanbury Brown and Richard Twiss. They …

Your article on health concerns surrounding eating wheat misses an important point (12 July, p 28) . Fad dieting is problematic not because of scientific controversy over whether non-coeliac gluten sensitivity is over-diagnosed, but because people don't heed science at all. In particular, they don't bother to consult a doctor about their symptoms before removing …

For passengers to feel safe, it seems we need a human presence in the cockpit (9 August, p 30) . This brings to mind the back pages of Flight magazine at least 20 years ago, when arguments began about whether two pilots or one were necessary. "In future, the cockpit will contain just one pilot …