Letters archive

Graham Lawton describes rewilding as letting nature run things, so it can right the wrongs we have done Earth's wildlife ( 13 October, p 34 ). It is easy to make a case for this in an area of virgin forest cut down a decade ago to produce palm oil. But where humans have been …

Technology probably can't answer the question of whether to prioritise the lives of pedestrians or vehicle occupants during a driverless car crash ( 27 October, p 6 ). But it can be used to give pedestrians a better chance of surviving. The biggest claim made by car makers is that driverless cars will reduce traffic …

Chelsea Whyte's article on who to spare in an accident highlights the different views on this of various cultures. Culture also affects science and hence may influence research on this subject. Surely the way to eliminate cultural bias is to let those creating the risk die and save innocent participants who are in harm's way. …

Questioning people about who they think should be saved in a road accident might be useful in developing some sort of morality basis for driverless cars. But it is odd to frame this in terms of whether pedestrians are criminals or doctors. When an accident is imminent, neither any humans involved nor any controlling artificial …

Driverless cars don't need ethics . What they do need is to be capable of following the rules of the road. The bits about not running into people are common sense. Leave the ethics to philosophers. The wider point in this debate is that driverless cars wouldn't be distracted by mobile phones, drunk, drugged or …

We are asked whose life our driverless car should spare in a crash: a family of four in the car or "a pregnant woman, a doctor and a criminal" who are standing nearby? Is the latter one, two or three people? Does the car's decision depend on how stereotypically it thinks?

I have serious concerns about how this will contribute to the debris environment Alice Gorman ( @drspacejunk ) is not thrilled at Elon Musk's plan to put 4425 satellites into orbit every 5 years ( 10 November, p 5 )

So cats are bad at catching adult rats ( 6 October, p 15 ). But cats do like catching and eating juvenile rats, which have a fighting weight a fraction of an adult's. I have seen the neighbour's cat trot by with a young rat in its mouth.

• Natalie Starkey is now a freelance writer and science communicator ( 3 November, p 38 ).

As a radio-communication engineer, I am surprised at the choice of the term "fast radio burst" (FRB) for the mysterious bursts of radio-frequency energy detected in space ( 27 October, p 8 ). Surely these emissions travel at the same speed as any other electromagnetic energy? Better terms would be: brief radio burst (BRB) or …