Letters archive

Hans van Haren correctly points out that tidal flow is not likely to meet all our energy needs, but his suggestion that it is therefore not worth trying to exploit this energy source is wrong (3 April, p 20) . No single resource can ever provide all our energy. "Only" 20 per cent of our …

Your catalogue of efforts to reduce the wholesale rape and pillage of our precious planet was fascinating (13 March, p 34) . However, you make no mention of the motivation behind these disparate initiatives and I would love to know more. Economists traditionally insist that effects on the planet are "externalities", which is to say …

Your interview with Joel Morgan, environment minister of the Seychelles, helped me understand something that had been puzzling me about the Copenhagen climate change summit last December (27 March, p 25) . Why were Tuvalu and other small, low-lying island states treated with such hostility by the big players when they insisted on strong, binding …

Nic Fleming's article on semi-autonomous vehicles was far more rational than most of us are when it comes to our cars (3 April, p 34) . Presumably a semi-autonomous vehicle would be programmed to keep to the legal speed limit. But how many of us want to do that consistently? Those who oppose speed cameras …

Jared Diamond and James Robinson argue that "natural experiments are not inferior, second-class science" (27 March, p 28) . I disagree: natural experiments are not experiments at all but observational studies. In the case of the historical epidemiological study discussed, John Snow thought the cholera outbreak in London was due to a water-borne disease. To …

Peter Aldhous reports that test subjects who make green choices subsequently exhibit a greater tendency to lie and that people who improve their homes' energy efficiency thereafter use their heating more (27 March, p 11) . Is this a general facet of human nature that also exhibits itself in dietary choices? Does ordering a skinny …

E. O. Wilson says, of his new novel Anthill : "This is the first time anyone has written about the lives of ants from their point of view" (10 April, p 38) . Wilson seems unfamiliar with the works of the French science-fiction writer, Bernard Werber. In the 1990s, Werber wrote the trilogy Les Fourmis …

Bob Holmes reports on evolutionary biologist Mark Pagel's theory that speciation is best explained as a consequence of single accidental events rather than by the gradual changes caused by natural selection (13 March, p 30) . This resonates with Nassim Taleb's suggestion in his book The Black Swan: The impact of the highly improbable (reviewed …

Nic Fleming's article on the safety issues arising from the increasing computerisation of cars (27 March, p 20) put me in mind of a safety solution based on a close call I once had. Driving at about 80 kilometres per hour in a snowstorm, I became suddenly aware that the throttle pedal was no longer …

I was pleased upon reading Linda Geddes's piece on changes in vegetation around animal graves (10 April, p 18) to see another example of folklore being vindicated by science. In the part of rural Somerset in the UK where I grew up, nobody would dream of planting an asparagus patch without first inserting a dead …

• RNA-based viruses replicate in the host cell's cytoplasm. The mimivirus, on which we reported, joins the poxviruses as the only DNA-based viruses to do so (10 April, p 10) . • The research we reported in our article on carnivorous plants and heavy metals was carried out by Iain Green and Christopher Moody (10 …