Urban myth
The notion that the city is greener than the countryside is rapidly becoming a modern myth. But Shanta Barley misses the fact that what happens in cities and the countryside are inextricably linked (6 November, p 32).
If you assume that deforestation and industrial agriculture are afflictions of rural life that have nothing to do with urban resource demands then cities can look pretty green. The same is true if you assume that the essentially urban lifestyle of modern country dwellers, with their energy-hungry cars and houses, is the only rural life possible.
Yet many rural peoples have historically provided for themselves without long-term resource degradation. We could learn from these models.
The main reason for the rural flight to the city is that country dwellers are peculiarly vulnerable to exploitation by urban 鈥� and rural 鈥� elites. Sensible proposals for rural land reform would deliver more ecological benefit than another romantic paean to the dynamism of the urban slum.
From Marc Mills
If the exodus to the city should “lift the strain of intensive agriculture from the land”, as Shanta Barley states, where will those urban immigrants get their food? Will it be grown in their living rooms? People do not stop eating when they move to a city.
Barley quotes David Lee on biogas: “You need to hit a certain scale of waste generation for that sort of methane capture to be efficient and economical”. This flatly contradicts Sujata Gupta’s article from the same issue, in which it is stated that a backyard 1000-litre biogas digester can produce enough methane to run a fridge for 16 to 20 hours (6 November, p 14). Installing one of these in every house would be cheaper than a sewerage system, and would also cut the amount of waste that goes into landfill.
Torquay, Queensland, Australia
Carbon farming
One thing missing from your list of 50 ideas that will change science (16 October, p 32) is the idea of farmland as a dynamic carbon sink.
Permanent pastures store large amounts of carbon, and organic matter can accumulate in systems such as permaculture in which ploughing is avoided. We also know that a young or newly coppiced stand of trees accumulates carbon, whereas the carbon balance of established forest is closer to neutral.
This knowledge can be combined to create novel farming systems which could be instrumental in mitigating climate change.
Recent research shows that systems associating trees with arable crops lead to increased production per unit area. In published by Agropolis International, a scientific community for agriculturalists, Christian Dupraz of the French National Institute for Agricultural Research wrote that yields of both poplars and winter cereals are greater when they are grown in association rather than in single culture. He suggests this may be due to modified rooting patterns in the mixture, with the trees rooting more deeply, so avoiding drought stress in the summer.
If nut trees formed part of such a system it could further boost food yields, providing a healthy alternative for meat. This is important if we in the west are to reduce our consumption of animal produce.
Sylvo-arable systems might be in their infancy, but with so much land devoted to farming, and demand for food increasing, they deserve our attention. Changing the focus from single crops to the system as a whole and the soil as a carbon sink would revolutionise farming. As a bonus it would be good news for biodiversity.
Network overload
At the GSM Association, which represents the interests of the mobile communications industry worldwide, we have a slightly different take on the problem of smartphones overloading networks from that in your article (30 October, p 44). We agree there is a wireless capacity issue, but think developments in mobile technology will help.
For example, the next step in the evolution of mobile technology, LTE, will offer an efficiency 12 times as great as today’s technology. Alongside investment in connections from base stations to network, this will allow cellphone operators to serve customers with much faster data rates than today to stop bandwidth running out by the 2012 Olympics.
Beyond this, the recently ratified 4G technology, LTE-Advanced, will use the spectrum up to 25 times as efficiently as today’s. That should take us to the 2018 FIFA World Cup.
In the long term, it is important to consider wider use of the spectrum. The mobile industry has about 10 per cent of the prime spectrum, between 400 megahertz and 5 gigahertz, and radar and the military have over 50 per cent.
In the UK at least, maybe now is the time to consider government usage of spectrum as part of its wider spending review. However, because of the advantages of having very many devices built for common frequency allocations and the need to avoid interference, spectrum allocation in the UK needs to be harmonised with our European neighbours.
The editor writes:
鈥� The peak spectral efficiency of LTE will bring big improvement to users whose mobile devices receive strong signals, but a for typical user, average spectral efficiency is a better measure. Simon Saunders of Real Wireless, a consultancy in Pulborough, West Sussex, UK, tells us that LTE will in practice only squeeze about 1.5 times as much data into a megahertz of spectrum, not 12 times as much.
Weird ways
The question “Who’s the oddball?” is not only fascinating but also politically significant (13 November, p 42). The WEIRD 鈥� western, educated, industrialised, rich and democratic 鈥� people the article describes are behind a lot of western, particularly American, policy towards China: and a dangerous policy it is, too.
WEIRD people, Laura Spinney tells us, “have more of a sense of existing as autonomous individuals than do people from East Asia, who are more likely to see themselves as inseparable components of a larger community”. The west’s highly vocal support for the awarding of the Nobel peace prize to human rights activist Liu Xiabo, defended by the chair of the Norwegian Nobel committee, Thorbjorn Jagland, , was typically WEIRD.
Kishore Mahbubani of the National University of Singapore , also in the NYT, on 12 November: “In the western political imagination, the march to progress is made by steadily weakening the state and enlarging individual freedom. In the Chinese political experience, the weakening of the Chinese state has inevitably led to chaos and enormous personal suffering… The past 30 years since Deng’s reforms began have been the best 30 years since the Opium war of 1842.”
Many who see China through WEIRD glasses want to punish the country for not sharing our WEIRD views and doctrines, forgetting that these are just our particular formulation of human rights.
From Bob Gibson
After reading your article on WEIRD people I felt compelled to return to the subject of bowerbirds and optical illusions (18 September, p 16 and 16 October, p 26).
If cultural differences affect whether an optical illusion is perceivable by different peoples, it would be especially difficult to devise an experiment that could determine if non-human species 鈥� let alone bowerbirds 鈥� could respond to optical illusions that are known to affect “western, educated, industrialised, rich and democratic” people.
Eastleigh, Hampshire, UK
Eating Skippy
Wendy Zukerman states that “kangaroo meat was not available in Australia for human consumption until 1980 鈥� 20 years later than most countries it was exported to”. Not so. When I was at the University of Melbourne in the late 1950s, kangaroo casserole was available every Thursday in the student union eatery.
It was a delightful dish, which I looked forward to each week with great anticipation. I guess that today’s uni students would be appalled at the thought.
From Mattie Pochee
It seems to me that all the arguments for kangaroo farming could equally well be applied to Australia’s camels. These perfectly adapted and healthy animals are wastefully and often inhumanely culled. Perhaps meat from browsing animals has even more to offer than Zukerman anticipates.
St Ives, Cornwall, UK
Inductive research
Ian Roberts rightly highlights the misinterpretation of medical case studies that has encouraged some clinicians to use treatments which have not been evaluated (25 September, p 28).
Unlike randomised trials, case studies were never intended to test a hypothesis and therefore cannot indicate that a particular treatment is effective. They belong to a completely different research strategy, an inductive strategy, which is exploratory and descriptive. Such strategies have a strong role to play in science, but they should be used at a much earlier stage than deductive strategies based on hypotheses.
Inductive research informs us of possibilities, which need to be shaped into putative theories and then hypotheses before further testing. Charles Darwin used this form of research powerfully; these days, it is sometimes overlooked and often misunderstood.
To understand the power of inductive research, it is worth remembering that it was a case study by W. G. McBride () which drew the attention of the medical profession to the possible risks of the drug thalidomide.
Time travel test
This letter is a test of quantum time travel (20 November, p 34). I, in your past, am sending you, in my future, a message. When you print this, in my future, you will, by post-selection, be sending me, in your past, a message telling me what to type when I have finished my cup of coffee. PS: It works.