Letters archive

Max Starkey says he is bilingual and thinks in concepts and images, rather than either language (Letters, 7 December 2019 ). My experience is different. When I came round in hospital after a stroke, I was relieved to be able to understand what had happened and what was said to me, and also to be …

You mention the fundamental technology of packet switching being developed in the early 1960s by independent groups of researchers in the UK and the US ( 26 October 2019, p 34 ). Paul Baran's team at the US RAND Corporation came up with the idea of independently routed "message blocks", while researching ideas for networks …

The many hypotheses as to why berries found under power lines may be larger and juicier than those elsewhere are fascinating (Letters, 23 November 2019 ). Looking out of the window at birds on a wire makes me wonder about waste products from birds falling under the cables, adding fertiliser and perhaps making the berries …

Bird excrement contains nitrogen, potassium and phosphorus – all essential macronutrients for fruit production , as gardeners know.

You suggest that near-death experiences (NDEs) may be caused by lack of oxygen to the brain ( 23 November 2019, p 40 ). But this usually produces chaotic, hallucinatory experiences, confusion and memory loss. NDEs are unlike this. They are serene, structured and well-integrated. It has been suggested they may be caused by psychedelic chemicals …

Archaeological evidence for afterlife beliefs goes back at least 12,000 years, when bodies started to be buried with useful stuff to take to the other side, says Graham Lawton . But there are other reasons to bury such items. Those left behind may gain a feeling of closure by burying their loved one with things …

I was interested in your article about those who need very little sleep ( 26 October 2019, p 18 ). I am one such person and, at age 77, I would like to meet others. Some of my relatives and ancestors have or had the same ability. In relationships, like attracts like. "Never sleepers" tend …

Humans aren't the only land mammals to undergo menopause ( 9 November 2019, p 16 ). Adult female rhesus macaque monkeys ( Macaca mulatta ) have menstrual cycles of approximately 28 days. Those that live long enough experience menopause at some point between 24 and 29 years of age.

Gege Li reports work to modify bacteria so they consume carbon dioxide instead of sugars ( 7 December 2019, p 19 ). This clearly requires energy: that would have to come from the sun or from chemical energy, and supplying the latter generally involves producing CO 2 . I would hope to see a more …

• Brass is an alloy of copper and zinc, and bronze of copper and tin ( 14 December 2019, p 10 ). • A white dwarf star is made of atoms, and doesn't collapse further because that would require their electrons to occupy the same energy levels, contrary to the rules of quantum physics ( …