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I would like to reassure readers that the Antarctic Treaty, which regulates activities on the frozen continent, is not under imminent threat as Andrew Donaldson declares (22 September, p 24) . The situation is the complete opposite. The Antarctic Treaty is one of the most successful international agreements ever signed. It has preserved the region …

Psychologist Paul Ekman asserted that about 4 to 5 per cent of the population can lie without giving any sign of doing so (15 September, p 54) . Can the true figure really be so low? Can he be sure that there does not exist a breed of super-liars so skilled that they have successfully …

Your report on the failure of traditional approaches to saving endangered species comes as no surprise (15 September, p 6) . In my department we long ago abandoned the hope that by simply appealing to aesthetics and morality we would protect biodiversity, especially if this is done in an ethnocentric manner. We are also sceptical …

Emma Young's feature on fertilising the oceans to sequester carbon from the atmosphere reflects a flaw in the way the proposal to use iron for this is discussed (15 September, p 42) . As she explains, although iron seeding will allow plankton to take up extra carbon dioxide, much of the resulting organic carbon will …

In arguing that we must leave Earth to ensure human survival, Richard Gott ignores important moral questions (8 September, p 51) . He assumes that it is morally justifiable to expend a large share of global financial and technical resources to ensure the genetic survival of a few human specimens and their descendants. He assumes …

I'm not convinced that Henrik Ehrsson's simulation of an out-of-body experience proves what he says it proves (1 September, p 20) . He shows that someone can be fooled into thinking that their self is somewhere else. He seems to be assuming that the mind is in the body, then saying he has proved that …

Nick Webb asks whether a pair of identical twins, one with a red wallet, one with a green, is a working analogy for quantum entanglement (22 September, p 25) . The editor's response was "it's exactly right" – but in fact it's exactly wrong. This is the fallacy described by John Bell in his paper …

In his article on the demise of the Yangtze river dolphin, Mark Carwardine states that the baiji is the first cetacean species to become extinct due to human activities (15 September, p 50) . I believe the Atlantic grey whale was hunted to extinction by European and American whalers. • It depends at whether you …

Ben Crystall describes a scheme "to initiate nuclear fission in... say, deuterium and tritium" (8 September, p 62) . You won't get those to undergo fission, at least not with any energy gain. • The scheme we mentioned starts out with fission to generate energy to trigger fusion. One reaction involves antiprotons, uranium, deuterium and …

• We quoted Philip Boyd describing "multiple research trips with aircraft and helicopters and up to 50 scientists involved..." (15 September, p 44) . That should have been "ships", not "trips".

In your article on endangered livestock, I was interested to see that you name the N'Dama as one breed that needs saving (8 September, p 18) . Readers may be interested to know that the genes of the N'Dama are indeed being saved and multiplied by the growth of the Senepol breed, which contains at …

In a piece on perfect pitch, you write "Mozart had it; Leonard Bernstein had it; even Jimi Hendrix reportedly had perfect pitch..." (1 September, p 20) . What did you mean by "even" Jimi Hendrix? It seems an oddly derogatory remark about a musician widely regarded as one of the most talented guitar players of …