Letters archive

Your position against banning travellers arriving from the three countries affected by the Ebola outbreak is well intentioned, but I don't think it is realistic (25 October, p 3) . You compare an entry ban to that imposed by the US in 1987 on people who were HIV positive, but Ebola isn't the same as …

• We argued that it is unlikely that Ebola can be contained in West Africa by closing borders – but such closure might well precipitate the collapse of our ability to control its spread. Given a choice between sporadic cases elsewhere, and uncontrolled spread, the best way to prevent an Ebola outbreak at home is …

Colin Barras's article on revolutionary ideas included details of milestones in human evolution (25 October, p 32) . The relation of two events surprised me: we are told that humans started wearing clothes about 70,000 years ago and invented the needle about 60,000 years ago. Were our ancestors wearing clothes for 10,000 years before someone …

• Necessity is the mother of invention, so they say. Given that our ancestors didn't make it out of Africa and up to colder latitudes until around 60,000 years ago, they probably had little need for snug-fitting clothes.

I was very interested to read the article on innovations that have shaped the evolution of the human species. But one very necessary ingredient seemed to be missing: women. Your front cover showed the stereotypical male hunter-gatherer and the graphics throughout were clearly male. The only picture to include a woman relegated her to being …

Examining the possibility of a world without fossil fuels, Michael Le Page comes to the conclusion that global warming may be an inevitable result of any industrialised civilisation, as fossil fuels are an unavoidable phase of that development (18 October, p 34) . He also notes that this might explain the apparent absence of extraterrestrial …

• We will never know for sure. But it is likely that a critical mass of people as well as energy is needed to reach something we would recognise as an industrialised civilisation.

I cannot accept Molly Sauter's conceptualisation of a distributed denial-of-service (DDoS) attack as an exercise in free speech (25 October, p 27) . Freedom of speech requires you to be able to declare your political views in a manner that ensures everybody knows you have them and can enquire further. For example, striking workers can …

I enjoyed Tiffany O'Callaghan's article exploring whether typing lecture notes aids or hampers learning (1 November, p 40) . Way back in the late 1950s, my college biology teacher Jack Halliday used to repeatedly admonish us to "listen and look" rather than scribble down notes. The sight of 20 or so heads bent over notebooks …

I can confirm from personal experience that "typing rather than writing by hand may alter the way we think", as your recent article suggests. Twenty years ago I took an exam in which three essays had to be written. In my job I used a word processor daily, and I had become used to typing …

Aviva Rutkin reports that a group of middle-aged people fed 900 milligrams of cocoa flavanols a day showed memory improvements on par with brains 30 years younger (1 November, p 18) . But we were told that to get these effects by eating chocolate you would have to consume so much you would damage your …

The Volocopter might beat congestion on the way to work (25 October, p 19) , but how many of them could you fit in the average car park? Until these machines can fold up into a space no bigger than the average car, they will remain a niche product, useful in some specialist situations and …

While touting flying machines for individual commuters, did you consider the noise generated by a machine capable of lifting and carrying a human in directed flight? Have you ever listened to a Volocopter? A jet-pack? A plain old ultralight aircraft? What sort of planet would Earth be if the skies were full of roaring, buzzing …

I wholeheartedly agree with Mike Belton's sentiments on artificial intelligence replacing the human search for knowledge (25 October, p 31) . But I can't work out if his tongue was firmly in cheek when he asked: "If you could find out anything by typing a question into the internet, would there be any meaning to …

Laurence Steinberg provides a well-reasoned argument for science to inform voting age (11 October, p 30) . However, voting age is not a scientific issue but a political one, as he acknowledges. The privilege to vote shouldn't be based on age, but on responsibility. The world has largely replaced "taxation without representation" with "representation without …

Abigail Beall writes that storing excess wind power as compressed air is "not such a bad idea after all" (1 November, p 50) . It is one way of easing the peaks between electricity supply and demand, but by itself it isn't a particularly efficient way of achieving it. Compressing air requires a significant amount …

Aviva Rutkin's article on Google's same-day delivery service confirms my opinion that we have become a decadent society inhabited largely by self-obsessed idlers (25 October, p 22) . In the time it took for her nail polish to arrive she could have gone to a shop and bought some – she writes from Boston – …

• Up in smoke: our special report on e-cigarettes credited Clive Bates as director of ASH (1 November, p 35) . The organisation is currently headed by Deborah Arnott