Letters archive

How can anyone know that the "Roman invasion left no genetic legacy" (21 March, p 10) ? Many of the prominent invasions of the UK featured an elite warrior class from a particular place taking control. Often, most of the soldiers bearing arms were not from the same places or countries as the elite. In …

• Indeed, the majority of the Roman soldiers posted to Britain were not Italian, but recruited from Gaul and Germany: but the point remains that the Italian elite hardly left any genetic imprint.

Asifa Majid points to the paucity of the English language of smell (28 March, p 27) . Could the issue lie in our noses? For example, I can recognise a musty smell, but my wife finds musty smells on items that have no such smell to me – clearly there is a chemical in the …

That article on belief was one of the most enlightening things I've ever read @charliparkinson on Twitter in response to "I believe: Your personal guidebook to reality" (4 April 2015, p 28)

Regina Nuzzo describes someone with a frequentist approach to statistics tossing a coin for a drink in a pub (14 March, p 38) . They would be a dull drinking companion, insisting that when a tossed coin lands unseen in the hand it isn't sensible to talk of the probability of it being a head. …

Bob Holmes names China as a "bad apple" that causes "harm out of all proportion" because of its carbon dioxide emissions (21 March, p 46) . This seems eminently unfair. China has a population equivalent to about 20 other countries put together. To be fair, one should look at the carbon dioxide emissions per head. …

I have enormous respect for Andy Haldane of the Bank of England, but his interview hides the constraints under which he operates (28 March, p 28) . The book he cites, This Time is Different by Carmen Reinhart and Kenneth Rogoff, presents the message that the main cause of financial crashes is letting banks (and …

You ask "Should we thank god for civilisation?" (28 March, p 5) . But what counts as "god"? Cults that honour dead human ancestors are common among tribal peoples, and consistent with the elaborate burials we find from very early on. They may coexist with the idea of gods and goddesses, with some gods viewed …

Agnosticism and atheism are not vague or interchangeable terms, as apparently claimed by Connaire Kensit (4 April, p 57) in response to my letter. The Concise Oxford Dictionary defines an agnostic as one "who believes that nothing is known or can be known of the existence or nature of God". This implies existence or non-existence …

Ian Simmons suggests that "alien civilisations may be out there, but have never managed to visit us simply due to budget cuts" and Adrian Ellis that "It's the quiet ones that are clever, not the shouters" (7 March, p 53) . Perhaps a civilisation a billion years more advanced than ours did visit undetected, said …

Your article on radio bursts coming from space mentioned the categorisation of other possible civilisations (4 April, p 8) . A Kardashev Type III civilisation is defined as one that controls the power output of a galaxy. Could a Type IV civilisation control the power output of its entire universe? What would this look like …

I was interested by your article on the possibilities of swapping body parts (28 February, p 10) . This was explored by Gordon Rattray Taylor in his 1968 book The Biological Time Bomb , raising some of the practical and ethical consequences of such procedures. One problem of a head/body swap that he foresaw would …

In your special report on the future of healthcare in the UK, you say: "If the low rates of cancer seen in the richer portion of UK society were replicated across the nation, 19,200 fewer people would die every year" (21 March, p 22) . People who don't die of cancer die of something else. …

I was amused to see the "rising threat of heat" discussed right next to the "winter crisis" in your special on challenges facing the UK National Health Service. I presume the winter crisis is a surge of illness caused by cold weather. So which is worse, warm or cold? Houston, Texas, US

• Death and illness from extreme heat will rise with climate change. Despite the continued possibility of extreme winters with climate change during the 21st century, death and illness from extreme cold will drop, but drop less.

If I am to believe New Scientist , we are about to enter a glorious age of leisure with robots doing all the work, electric cars driving us to beauty spots and other planets being available via space travel, if we get bored on Earth. Such is the gist of many of your recent articles …

• The correct reference for an article on panda sociability by Vanessa Hull et al is DOI: 10.1093/jmammal/gyu031 (4 April, p 17) . Not "jmamma": our therapist is concealing her glee. • We now know that, in our article on belief, the extensively quoted neuroscientist at George Mason University in Fairfax, Virginia, should have been …