Letters archive

Further to the observation of fairy wrens breeding out of season in Western Australia in recent years, since drought ended in Australia in 2021, we have had some of the wettest years for a while ( 15 January, p 25 ). It isn't uncommon for native species to bring up two batches of babies in …

You report that chimpanzees may be the first animals seen to apply insects to wounds, but there are a number of bird species that use ants to treat skin parasite infestations, exploiting the formic acid from their stings ( 12 February, p 10 ).

Your article says an ocean may be hiding under the ice on Saturn's small moon Mimas ( 22 January, p 18 ). Given the suggestion that water is sloshing around under the ice, is it possible there is a layer of gas between the ice and the liquid? If the minerals beneath were releasing gas, …

The International Garden Photographer of the Year competition ( 12 February, p 30 ) is organised by IGPOTY. Quick quiz (12 February, p 55): Titan, which is the second largest moon in solar system, orbits Saturn.

James Ball discusses some reasons why people are nervous about new technologies ( 19 February, p 27 ). Here is another: risk. Some technologies, such as the burning of fossil fuels, come back to bite us. We deploy new technologies globally and rapidly with no idea of the long-term consequences. The internet brings benefits, but …

I can imagine that we humans influence space-time, but not that we create it, as you suggest in your new perspective on quantum reality ( 5 February, p 38 ). Who created space-time when humanity didn't exist? I always had difficulty with Schrödinger's cat. For me, it is clear that the cat is either dead …

A particular nuance of happiness has been overlooked ( 22 January, p 38 ). In her novel A Closed Eye , Anita Brookner touches on it when one of her characters reflects thus: "Happiness was what young people wanted; at his age he knew that comfort was more important."

After your look at happiness and the letters on it, I have found the formula for the elixir of happiness: Happiness = 1/unhappiness.

The state of Earth in 2022 is indeed in crisis, but tinkering with the economy isn't the answer ( Leader, 12 February ). The elephant in the room that few people dare to mention publicly is overpopulation of the planet. This silence must change.

Geoff Harding ( Letters, 19 February ) fears for fertility in our polluted world. As a species, we seem incapable of restricting our encroachment on, and destruction of, all parts of the planet. Human sperm counts too low for fertility may be the best hope for a world that continues to be fit to live …