Sugar cane drain
Marcos Buckeridge supports the use of biofuels as a sustainable alternative to fossil fuel, stating that because sugar cane does not grow in Amazonian climate conditions its plantations have no impact on pristine forests (23 May, p 26).
However, he does not consider the indirect impact of biofuels on the forest. Since biofuels were discovered as an alternative to petrol, sugar cane plantations have been replacing cattle ranches and soybean plantations in south-east Brazil. These in turn are being pushed into the Amazonian borders, where they are a factor in continued and rapid deforestation.
Buckeridge also suggests that forest areas can be conserved within sugar cane plantations. Yet the overspill effects of such plantations are extremely deleterious to the surrounding forest and legislation promoting conservation is poorly enforced. Consequently, the Atlantic Forest, one of the world’s most threatened biodiversity hotspots, still loses 34,000 hectares of forest each year.
It is clear that alternatives to petrol are needed, but this fuel is not yet the “greenest” solution.
Cyberwars
Jim Giles’s report on the Conficker worm (13 June, p 36) reminded me that I have always thought antivirus software, and indeed Microsoft Windows, shares many of the characteristics of a computer virus. After all, it distributes and updates itself on a population of PCs. That the vector of distribution is retail outlets is merely incidental.
I use one of the antivirus packages mentioned in the article, which is Russian in origin. Others are American or based in other countries. In the event of a decay in international relations, what is to prevent the use of these platforms to launch a cyberattack into another nation’s cyberspace? It is surely on someone’s agenda: Conficker your enemies.
Female prostate
Sharon Moalem’s article on female ejaculation raises many questions (30 May, p 31). Moalem wonders whether the female prostate ever performed an antibacterial or any other useful function, but if it had it is unlikely to have become vestigial.
The fact that the female prostate varies so much in size and shape, and is so frequently absent, suggests a comparison either with features whose original function has changed or disappeared, like the appendix or the skin’s pilo-erectile muscles, or functionless analogues of features from the other sex, like nipples in men. Is the amount of fluid discharged by these atypical females any more significant than that from the nipples of atypical males? And why is the ability to mess up the sheets in this way regarded as a desirable female accomplishment? Are there also “sex-educators” claiming to teach men how to lactate, and if not why not?
Moalem also points out that the existence of the G spot is still considered controversial. Surely it is possible to find out whether it exists. If the G spot is characterised by an unusually dense cluster of nerve endings at a particular location, it should be possible to count them.
Your article about female ejaculation made claims for the existence of a female prostate. While there is no doubt that glands adjacent to the female urethra may become enlarged and secrete significant volumes of ejaculate-like fluid, the presence of prostate-specific antigen (PSA) in this fluid is not proof of a prostatic origin.
PSA is produced in small amounts in females from a number of tissues, and has even been used as a marker for bowel cancer. If women have a prostate then you might expect rare cases of prostate cancer, just as men occasionally develop breast cancer. A search of the PubMed database revealed no such cases, so I can only conclude that the case for a female prostate remains conjectural.
Indooroopilly, Queensland, Australia
鈥� Prostate cancer in women seems to be extremely rare, but there are at least six known case reports. In one the woman had raised blood levels of PSA, just as with male prostate cancer ().
Perceived reality
James Le Fanu is disconcerted by the similarity between his genes and those of a nematode worm or a fruit fly (23 May, p 45).
He is perplexed when the simplest mental process activates many areas of the brain. He doesn’t understand how myriad sensory impulses are integrated into his “single coherent stream of conscious awareness”.
How this leads to the need to presuppose some hypothetical entity to produce the mind defeats me. Unlike the postulation of the atom, which explained much and predicted more, the purpose of Le Fanu’s entity seems only to be to satisfy his personal incredulity.
Genetics and neuroscience were never going to answer the question of what it means to be a human. As a doctor, Le Fanu could answer this question by talking to his patients.
From Matthew Willey
James Le Fanu calls for the creation of some hypothetical entity to unite the gap between the detail of science and his grasp of the metaphysical truth.
In calling for such a creation he holds up the postulation of atoms and quarks as an equivalent. He is missing the point that these entities, though invisible like his suggested one, were the logical extrapolation of current science and are testable by other means.
He finalises his piece by noting that science needs to find “a space to live and breathe again”, which suggests to me that he hasn’t been reading New 杏吧原创 recently.
Milson, Palmerston North, New Zealand
Made to last
Perry Bebbington asserts that old technology will inevitably be thrown away rather than repaired, but we still need to salvage components to reduce landfill (13 June, p 25).
Houses, furniture, kitchenware, everyday clothes, tools, leisure equipment and books can all be durable, repairable and reusable. My 100-year-old bread knife is better than kitchen knives you can buy today. In fact, most of my possessions are over 50 years old and still of high quality. In addition to maintaining consumables, 70 per cent of our food wastage is preventable.
Stopping our production of excessive waste saves more resources and carbon emissions more certainly and quickly than carbon trading or sequestration. Surely science can adapt our economy to cope with the changes that will be needed.
New model army
I was very interested in your articles on how advances in neuroscience may reduce confusion and post-traumatic stress disorder (PTSD) in soldiers, and help create future armies of super-soldiers (9 May, p 40, and 23 May, p 6).
However, soldiers in modern armies are already subjected to extensive conditioning. After the second world war it was discovered that only 10 per cent of combatants were firing their weapons. Moreover, 8 per cent were “firing for effect”, with only 2 per cent actually aiming at the enemy. Due to improvements in battle simulation, notably the switch from “bullseye” targets to the “charging silhouette” and even more realistic targets, most soldiers are able to fire at human figures during training without compunction.
The current high toll of PTSD may partly be the result of men who would otherwise be incapable of killing, being pushed beyond their moral horizon by conditioning.
Obama's intellect
In his article on Barack Obama’s new era of intellectualism, Chris Mooney derides what he sees as a long-standing antipathy towards intellectuals in the US (9 May, p 22). However, what he actually observes is a justified dislike of the arrogance of pseudo-intellectualism.
To see Obama’s new cabinet member Steven Chu, with his Nobel prize for physics, making unquestioning pronouncements about climate change is equivalent to watching a sea captain step into the cockpit of an aircraft and decide to fly the next leg of the trip. Competence in physics does not make someone automatically credible in his opinions on any other science, whether it is biology, chemistryor climate.
Mooney’s approval of Obama’s decision to use government funding for stem cell research seems more political than scientific: Bush never prohibited any stem cell research, he just did not give it government money.
As for Obama’s academic background, his two books are the equivalent of any young person’s musings about their own feelings, background and relationship to their world. Academics are supposed to contribute to the world’s knowledge. I do not think anything President Obama has yet done meets this criterion.
Science is the one area where opinions and theories are expected to be challenged; brooking no opposing discussion is clearly unscientific.
Pseudoscientists denigrate opposition as “vacuous, dollar-driven mass media”, taking their ivory-tower positions with the belief that anyone unable to appreciate their inherent importance just doesn’t understand. Perhaps instead their critics do “get it”.
Ancient chants
When discussing the rongo-rongo script of Easter Island, Andrew Robinson states that the direction of reading is unusual, though not unique, with lines being read from alternating sides of the tablet (30 May, p 24).
Given the awkwardness of this reading style for an individual, and the fact that “rongo-rongo” means “chants” in the islanders’ native language, Rapanui, I would suggest that the tablet is instead meant to be read by two individuals facing each other in a “call and response” manner, as used in many religious ceremonies.
Ad hominin
I was intrigued to see (30 May, p 7) that “Tafforeau and colleagues recently showed that Neanderthals grow up only slightly faster than humans and are now studying other hominins”. Is there any chance of these Neanderthal researchers sharing their findings with us?
For the record
鈥� The experimental reruns involved in the discovery of element 112 occurred three years earlier than we stated, in 2000 (20 June, p 10). Also, we confused celsius with kelvin when giving its boiling point. It is in fact around 80 掳C not “around 300 掳C” as we said.