30 | NewScientist | 17 December 2011

Fried mushroomsFrom William BainsYour article on the evolution of warm-bloodedness as a means to avoid fungal infection ends with speculation that global warming might drive the evolution of more warm-tolerant fungi, and lead to a raised risk of fungal pathogens in both mammals and birds (3 December, p 50).

This ignores what the rest of the article says. Fungi have had a tempting, warm environment to adapt to for hundreds of millions of years – the insides of mammals and birds – and they have not been able to do it. This suggests a more basic limitation in the biology of fungi that stops their adaptation. Increasing the number of warm places for fungi to grow is unlikely to overcome this limitation, whatever it is.Cambridge, UK

Bright ideaFrom Simon SellickJames Mitchell Crow’s article about thermoelectric solar panels mentioned that photovoltaic (PV)

materials respond to only a narrow spectrum of frequencies, the remainder being either too feeble to trigger the photoelectric effect or too energetic and a hindrance (26 November, p 38).

Might the yield be improved by using a trick similar to that in fluorescent lighting, where ultraviolet light is converted to visible light? The conventional solar panel could be coated with a material that absorbs a wide spectrum and fluoresces at the optimal frequency for the PV material, thus harvesting more of the available energy and avoiding the disruption caused by high-energy photons. If a coating is not feasible, perhaps a reflector to direct light towards the panel could work.Ashton under Hill, Worcestershire, UK

Yawns all roundFrom Giuseppe SollazzoJan Chamier writes that her cat yawns when she or her husband does, and speculates that this is an example of contagious yawning in the animal realm

(26 November, p 32). I have a better example. As I was reading her letter, I started yawning as soon as I read the word “yawn” – contagious yawning from reading about the contagious yawning of a cat. Even now, I am yawning as I write this letter.London, UK

Climate blameFrom Robert Thorniley-WalkerMaybe popular TV documentaries highlighting life in the polar regions and the impact that global

warming will have on the area will initiate what your story called the “climate blame game” (12 November, p 6).

However, from now on legal negligence could be determined simply by looking at the risk assessment, or the lack of one, drawn up when the carbon was released. My paper “Carbon footprint and risk assessments”, published in ICE Energy (DOI: 10.1680/ener.2011.164.4.147), considers the UK Engineering Council’s advice to assess the risks to distant people from emissions for all projects.

From a limited survey of engineering opinions, my paper suggests that the hazards to life and the probabilities of these hazards occurring are both orders of magnitude worse than normal civilian dangers. Action or mitigation is therefore essential. There could be rich pickings for the lawyers.Northallerton, North Yorkshire, UK

Heads in the cloudFrom Stephen WarmanIt is good to see that biologists are beginning to recognise that, as there is more to the nervous system than just what’s in your head, the rest of the body has a contribution to make to mental responses (15 October, p 34). How long before we appreciate the importance of the networks of brains in interactive societies? It is tempting to suggest that cultural activities are the outward manifestations of “cloud” thinking.Truro, Cornwall, UK

Shells cracked From Peter JamesWhether or not biologist and mathematician D’Arcy Wentworth Thompson was partial to pasta is doubtless lost to posterity, but he did take a great interest in foraminifera. In his classic work, On Growth and Form (1917), he devotes a whole chapter, “The Spiral Shells of the Foraminifera”, to the sort of analysis which Tom Radford calls for in his letter on the mathematics of pasta (12 November, p 36).

Thompson had no access to computer graphics, but he made reference to experiments which showed that many of the forms found among the foraminifera could be generated by using mercury and chromic acid. Computer models are perhaps safer and less messy.Hunstanton, Norfolk, UK

Seeing the lightFrom Adam Justice-MillsElena Oancea at Brown University in Providence, Rhode Island, and colleagues have shown a link between skin and the light-sensitive chemical rhodopsin, which is also found in the retina (12 November, p 20).

If we don’t get enough sun on

Enigma Number 1677

OPINION LETTERS

WIN £15 will be awarded to the sender of the first correct answer opened on Wednesday 15 February. The Editor’s decision is final. Please send entries to Enigma 1677, New Scientist, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com (please include your postal address). Answer to 1671 Power engineering: ENIGMA is 876432 The winner Cath Brown of Birmingham, UK

RICHARD ENGLANDAlbion, Borough, City, Rangers and United have played a tournament in which each team played each of the other teams once. Two points were awarded for a win and one for a draw. In the final table the teams finished in alphabetical order, Albion with most points and United with

fewest, no two teams having the same number of points. There was only one instance of two matches having the same score. No team scored more than 4 goals in any one match. In the course of the tournament each team scored 6 goals and conceded 6 goals.

Borough beat Albion 3-0. What were the scores in (a) Borough vs City and (b) Rangers vs United?

Six of one

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