Letters archive

You report work on the viability of life that relies on photosynthesis in the sheltered zone of caves on Mars ( 4 September, p 9 ). As life has evolved to process energy from chemosynthesis on Earth, surely life on Mars is more likely to exist without any need for photosynthesis, especially given the proportionate …

David Hambling's interesting article on firing weapons from autonomous warships mentioned that any strike from an uncrewed ship mandated human control ( 18 September, p 11 ). Given that the last drone strike in Afghanistan was planned and executed by humans, resulting in the deaths of 10 civilians (seven of whom were children), maybe it …

In one part of your illuminating article on a net-zero life, you mention the fictional Isla planning a holiday that avoids the "moral opprobrium" of long-haul flights in favour of a train tour in Norway ( 4 September, p 34 ). While I agree that travelling by train is preferable to flying within Europe, I …

For the past two years, I have been putting all my food purchases onto a spreadsheet, detailing the quantity and use-by or best-before dates. Since I began, I have only wasted two items. I review the list daily and make my menu for the following day from it.

Some will say that using AI to identify targets for military strikes is a dangerous step down the road to mechanised, dehumanised warfare ( 2 October, p 14 ). Others will say that having two parallel decision processes, AI and human, will reduce, though not eliminate, error. Yet others will say that no targeting can …

Questions about such use of AI are raised by Arthur Holland at the UN Institute for Disarmament Research. He asks whether, in the case of an erroneous target selection, the use of AI might "affect the balance of human responsibility and accountability". I find this troubling because the question itself suggests we are yet again …

The experiments cited in your entertaining article on spite could cut two or more ways ( 4 September, p 40 ). For example, in the Ultimatum Game, the potential spitefulness of the "receiver" is considered in a one-play, known-rules, sharing game, yet the possible spitefulness of the "giver" goes unremarked. Why is it spiteful to …

You report that hyenas make a face when they want to play-fight ( 2 October, p 23 ). Cats also make play faces. Our 11-year-old arches her whiskers forward and opens her mouth slightly when playing. Her expression when hunting or fighting is very different – the play face can't be mistaken. I have had …

I have sympathy with the view that women don't feature significantly in the first book of Isaac Asimov's Foundation series ( 2 October, p 32 ). I would, however, point out that in subsequent parts of the trilogy, we do see three significant and strong women: Bayta Darell, Arkady Darell and Lady Callia. Perhaps Asimov …

Grace Maddrell, author of Tomorrow Is Too Late , uses they/them pronouns ( 2 October, p 33 ). A quote in our feature on AI ( 9 October, p 36 ) was partially attributed. It was made by Ellie Pavlick at Brown University in Rhode Island and Google AI.