Letter
The train indicators on the eastbound District line platform at South Kensington station often proclaim “Barking. No Smoking”. I have waited in vain to see “Smoking. No Barking”.
Letter
Margaret Thatcher was known behind her back as Lady Dagenham 鈥� three stops beyond Barking.
Mad about Barking
Feedback tells the story of the “Barking Police Dog Patrol” (4 October). My medical consultant brother-in-law came back from Toronto a couple of years ago and said that in his hospital there the expression for “mad” was “two stops short of West Ham”.
Barking is actually four stops short of West Ham on London Underground’s District line 鈥� but as the medics didn’t seem to know where the expression came from, does it matter?
Plant mimicry
Your article suggests that plants can use a form of mimicry 鈥� “automimicry” 鈥� usually only seen in animals. They can give predators the impression that they have more thorns than they actually have (30 August, p 15).
As a lifelong gardener, I’ve had ample opportunity to observe plants and their habits. I wonder if others have noticed something I suspect is more than a figment of my imagination. The plant Rhus toxicodendron, otherwise known as poison ivy, is common in the north-east US, where I live. Poison ivy exhibits some variability in its leaflet shape. The leaflet can be entire or have serrated lobes that are more or less prominent (and no, I am not confusing it with poison oak).
I have often discovered a poison ivy plant in an area I’ve weeded, only to realise that I missed it because its leaves were so similar to those of an adjacent plant. Is it possible that plants can receive chemical signals from neighbours that allow them to identify what is growing nearby and alter their own appearance in subtle ways to better “camouflage” themselves? I can think of numerous ways in which this kind of mimicry could be biologically advantageous.
Athletes on drugs
We welcome Robert Dawson’s desire to solve the problem of doping in sport (4 October, p 23). We at WADA have been busy for several months now, finalising the World Anti-Doping Code, which will for the first time harmonise rules regarding doping across all sports and all countries. The great majority of sportsmen and women want to play cleanly and fairly, and the code will be a powerful tool to stop cheats hijacking sport.
Dawson is correct in stating that the code will not solve all the problems related to doping. Educating young athletes about the dangers of doping, as he points out, is crucial in fighting this problem. That is why we have made education and outreach to athletes one of the top priorities at WADA. We are developing programmes and materials aimed at athletes of all ages to teach them not only what these drugs can do to their bodies, but equally importantly, that they do not need chemicals to succeed.
But we believe in a two-pronged strategy. Prevention alone is not enough. There will always, unfortunately, be cheats in sport, just as there will always be lawbreakers in society generally. That is why we develop a list of banned substances and test for them. That is why we have provided for suitable sanctions in the code for those who cheat. And that is why we continue to invest millions in research to develop new and better ways of testing for prohibited products to make sure the cheats lose the upper hand.
Life without lions
There may be fewer lions in Africa than you suggest (20 September, p 36). Our estimates, made in 2001, put the number at between 12,000 and 18,000.
However, we fundamentally disagree with Laurence Frank’s idea that lions can peacefully coexist with humans and livestock. Frank, a wildlife biologist from the University of California, Berkeley, studies predators on large ranches where owners seem quite tolerant of livestock losses. This is not the norm for Africa. In arid Botswana, for example, intensive cattle herding and corralling is not feasible. Despite government compensation and the introduction of a total ban on killing lions in 2001, stock raiders continue to be destroyed. Lions that coexist with humans are also at risk from diseases such as distemper transmitted from domestic dogs.
Frank’s “reluctant” proposal that problem animals outside protected areas could be shot as trophies as a way of conserving the remaining lions is very worrying. A similar proposal several years ago by hunters in Botswana was rejected as open to abuse 鈥� as amply illustrated in the Hwange area of Zimbabwe, where an absurd annual quota of 60 lions has reduced the “protected” population to around 50 animals.
The kings of the jungle are actually surprisingly fragile animals. If they are to survive, few further losses can be tolerated. Trophy hunting must be banned, lion habitat defended and the issue of disease urgently addressed. Sound modern conservation biology must be based on facts rather than fads, and this will require a much better understanding of reproductive biology and the impact of diseases.
Letter
The estimates of over 100,000 lions in the past were not based on data. Rather, they represented a range of guesses that reflected confidence 30 or 40 years ago that lions were then abundant in much of eastern and central Africa.
The African lion has declined drastically over the past century, but is not yet on the brink of extinction. However, the surviving population is much smaller than most people realise. Some very large protected or managed areas account for the great bulk of the population. Most of the remainder are scattered in small isolated parks, and those populations may not be large enough to be genetically viable in the long term.
Furthermore, given the potential for political instability in much of Africa, even the largest reserves and parks may change status abruptly. To secure the lion’s future, African governments and conservation groups must initiate science-based predator management plans linking protected and unprotected areas.
Incidentally, the current figure of 23,000 lions comes from a survey organised by Hans Bauer of Leiden University, in the Netherlands. He asked scientists across Africa who are members of the African Lion Working Group to give a rough estimate of how many lions they thought were in each country or reserve. It is not an accurate figure but a summation of everyone’s best guesses.
Software patents
Your article is not a fair reflection of the state of the proposed European legislation on the patenting of computer-implemented inventions (4 October, p 5).
The directive, in its amended state, reaffirms the European Patent Convention principle
that software, like mathematics, is not patentable. There may be slight glitches in some of the wording of the amended document, but this can be tidied up in committee prior to the second reading.
Many people would disagree with your description of the amended directive as “all but useless”, not least the quarter of a million European citizens and software professionals who have signed the petition against the introduction of software patents in Europe.
Software is already protected adequately by copyright law. The extension of patents into the realm of software is unnecessary and would have many adverse consequences for consumers, industry and academia within Europe. The amended directive provides a much needed restraint on the European Patent Office’s recent drift towards a US-style patent system.
Women and maths
Ragni Piene argues that the problem of a lack of women in senior positions in mathematics is a sociological one, and, by implication, open to change (27 September, p 44). This is too easy an explanation and requires statistical qualification on two counts.
First, Piene explains that between men and women “these are small differences in mean test scores [in geometry] 鈥� whereas variation within both the male and female population is enormous.” True, but Piene is set on selecting the best mathematicians and this has implications.
Consider the following analogy. On average, men are just a little taller than women compared with the enormous variations in height within both male and female populations. Now try choosing the 10 tallest people from a mixed-sex group of 1000 people selected at random. The chances are that all 10 will be men.
This is because small mean differences translate into heavy loadings at the extremes. So too with top mathematicians.
Secondly, it is well known among psychometricians that whereas the mean general IQ scores of men and women in a given population are the same, the spread is much greater for men than for women. Consequently we produce more male than female geniuses, but also far more male than female morons.
This is reflected in the observation that not only do men tend to dominate the top of most fields of human endeavour, but also that there are far more men than women in prison and sleeping rough on the streets. For every supposed glass ceiling stopping a woman getting to the top, we also need to explain an equally resilient glass floor that stops another dropping out.
Sociological rather than biological explanations for differences in achievement may be more comforting at an emotional level, and more appealing (for some) at an ideological one. But that does not make them scientific.
Time flows
The article on causal set theory was fascinating, and may even be the beginnings of a “theory of everything” (4 October, p 36). However, the one thing it did not address was the question on the cover 鈥� “What makes time flow?”
Whether one has a theory in which Planck volumes evolve, or one in which world lines criss-cross space-time (as in relativity), one is still dealing with a “block universe” in which, if one could view it from outside time, nothing would change. I could see nothing in the article that justified the view that causal set theory has reintroduced the philosophically and physically dubious notion of time as “flowing”.
Letter
Related work that I have recently done on this subject illustrates that if there were a “now” or actual physical “flow” of time in nature, all physical continuity, including motion, changes in physical magnitude, and time itself as it is measured in physics (relative duration) wouldn’t be possible in the first place (Foundations of Physics Letters, vol 16, p 343).
The “now” and seeming “flow” of time are entirely subjective and without physical foundation in nature. That is, we project them onto the world around us and they are the outcome of the processing of information in the brain and consciousness. I suggest that the reasons behind the brain’s innate conception of a “now” and “flowing” time are central in addressing the age-old mystery of consciousness and how it is possible.
Long-lived micelles
One snag with the proposal that micelles 鈥� balls of lipids 鈥� facilitated the origin of life is that the long surfactant carbon chains are of biological origin themselves (27 September, p 22).
However, micelles are interesting as crude models of life 鈥� they form, live for a certain time and then die. It used to be thought that they always form and break down very rapidly 鈥� not much use then as supports for any reaction between absorbed prebiotic molecules. This is true for surfactants made of carbon-12 but certainly not for the common ones, made of carbon-16. Over 40 years ago, I showed that the average lifetime of a carbon-16 micelle is around an hour.