Letters archive

Colin Barras reminds us that our 30 trillion human cells are outnumbered by 39 trillion microbes – a more accurate representation than Thomas Luckey's 1970 estimate that microbes outnumber human cells 10 to one ( 13 April, p 28 ). But over 80 per cent of the human cells that make up our bodies are …

While discussing the effects of cutting work hours, Michael Le Page quotes a study by Huong Dinh at the Australian National University showing that men with unpaid care commitments could manage about 30 per cent more working hours than women with such duties, without experiencing a decline in their mental health ( 13 April, p …

Harvey Whitehouse reviews evidence on religion's role in human civilisation ( 6 April, p 36 ). But he makes no attempt to distinguish between the differing social needs of women and men. Formal religions are staffed by a ruling elite of men who, I believe, have a fundamental goal of regulating women's sexuality.

A study investigated what people are willing to do voluntarily to reduce their carbon footprints, and concluded "not enough" ( 6 April, p 8 ). I think people would be happy to do far more if everyone had to do so. It is our leaders who need to be forced to make the necessary laws.

Adam Vaughan notes that the European Academies' Science Advisory Council urges the European Union to change its stance on transport, which is that curbing mobility is not an option ( 30 March, p 23 ). Social engineering has given us the transport situation that we have now: they built it, and we use it. But …

Vaughan suggests caps on personal travel to reduce carbon emissions. But if capped travel could be traded, a rich person could buy travel from poorer people who were happy to accept a market price for it. This would be equivalent to a fuel tax that raised the cost to that price and whose proceeds were …

Taxing meat to cut consumption is curious: many of us are already taxed in order to make it cheaper. The only step needed is for governments to stop subsidising meat and dairy. Doing so absorbs the majority of the EU agricultural budget , which itself comprises 40 per cent of the EU budget. Subsidies are …

Sam Edge suggests fitting street lights with motion sensors to save energy ( Letters, 16 March ). I would go further and provide a rolling corridor of light in rural areas. It would move along ahead of a moving vehicle. This might have the added benefit of "nudging" compliance with the speed limit if the …

Your article on chimpanzees losing culture brought back memories ( 16 March, p 16 ). I took an elective course in anthropology as a freshman at the University of Illinois in early 1961, but I had no real interest in the field. One day, our professor came in with a burly gentleman, who he introduced …

I am not at all surprised that Amélie Catala and her colleagues find that dogs can smell when someone has had an epileptic seizure. The reason for this is that I can smell when my dog has had one ( 6 April, p 19 ). My dog's seizures are generally well controlled by medication, but …