Join the conversation in Â鶹´«Ã½'s Letters section, where readers can share their thoughts and opinions on articles and see responses from experts and enthusiasts across a range of science topics. To submit a letter, please see our terms and email letters@newscientist.com
6 June 2018
From Brian Horton, West Launceston, Tasmania, Australia
Clare Wilson reports a "real life" test of the "trolley problem", in which subjects could allow five mice to receive a painful electric shock, or press a button to shock just one mouse ( 19 May, p 14 ). As in all cases of the trolley problem, the situation is so artificial that people try …
6 June 2018
Asteroids squished can form a planet. Pluto is comets squished and has a comet's eccentric orbit Brinda Thomas responds to people demanding that Pluto, found to be comets squished together, be called a planet ( 2 June, p 8 )
6 June 2018
From David Holdsworth, Settle, North Yorkshire, UK
Lara Williams comments that a male pill will be a breakthrough for science but not for women ( 12 May, p 22 ). She does not mention vasectomy. In my experience this allows a man to assume full responsibility for contraception without any need for interference with his body chemistry. Numerous jokes reveal, however, that …
6 June 2018
From Guy Cox, St Albans, New South Wales, Australia
Vasectomy is the commonest form of contraception worldwide. True, those who take it up are not teenagers but men wanting "end of family" contraception. Still, it prevents more pregnancies than any other contraceptive method. I can understand the appeal of a male pill to men who want to avoid condoms, though it might be counterproductive …
6 June 2018
From Perry Bebbington, Kimberley, Nottinghamshire, UK
Fred Pearce reports that developed nations expand their forests, while poorer nations lose them ( 19 May, p 6 ). Developed countries might well use less firewood, but surely that is because they have replaced firewood with fossil fuels, hardly much of an improvement. In any case, developed countries are beginning to use firewood on …
6 June 2018
From Gregory Paul Baltimore, Maryland, US
Colin Barras writes that dinosaurs were "reinstated as a scientific fact" in the 1980s ( 5 May, p 38 ). But in 1974 Robert Bakker and Peter Galton published "Dinosaur monophyly and a new class of vertebrates" ( doi.org/ftw3f9 ). This led to dinosaurs being widely accepted as a single distinct group. Almost all phylogenetic …
6 June 2018
From Jackie Jones, Brighton, East Sussex, UK
In your article about the effects of not drinking alcohol for a month ( 19 May, p 7 ), you noted a drop in blood pressure and a 1.5 per cent decline in weight. I am not sure that all the benefits were the result of abstaining. Participants had previously been drinking three bottles of …
6 June 2018
From John Phillips, Hughenden Valley, Buckinghamshire, UK
Chris Baraniuk reports virtual training environments for troops ( 28 April, p 8 ). The obvious next step is to fight the war itself entirely within the virtual world.
6 June 2018
From Ben Dallimore, Isle of Luing, Argyll and Bute, UK
Your letters about the nature of time have been interesting. Rod Munday suggests that the future consists of events of which there are as yet no memories (Letters, 19 May ). But consider the future from the perspective of an observer just prior to the big bang. There was undoubtedly a future as a number …
6 June 2018
From Tillmann Benfey, Fredericton, New Brunswick, Canada
You reproduce a widely circulated image of an emaciated polar bear limping across a barren landscape ( 10 February, p 35 ). I often wonder whether it simply shows an old animal near the end of its natural life. This by no means detracts from the importance of understanding and mitigating the effects of climate …
