Editor's pick: Ecology precedes economics
In your Leader you appear to suggest some kind of equivalence between ecology and economics (21 November, p 5). Surely there is a hierarchical relationship here?
Economic activity attempts to explain the exchange of goods within society, while society itself is embedded in and interconnected with the wider (natural) environment. The economic therefore is embedded within the social, which is itself embedded within the ecological 鈥� that “triple bottom line” so beloved of those on the economic side who pay lip-service to the ecological is therefore not truly linear.
Such a scientific understanding is crucially important in a world where many appear to believe that economic laws can somehow override natural laws. The only way to reconcile the economic and the ecological is for the economists to understand their place within this wider ecological context.
It is in fact crucially important that we move away from the current economic understanding of the world and turn instead towards an ecological understanding. Without such a shift we are in trouble.
Cardiff, UK
Can violence be treated as disease?
I am not convinced treating killing as a disease will work (14 November, p 40). As Steven Pinker wrote in his book , for most of human history violence has been much more common than we now take for granted.
What is remarkable isn’t that some people kill, but that in the modern world so few do so. Surely, most have wished at times, however fleetingly, to be free to administer summary justice.
Stirling, Western Australia
Can violence be treated as disease?
To understand how a person can be made to overcome an aversion to killing others, look at military training and the inculcation of a belief system that justifies committing violence as being lawfully sanctioned.
Distinguishing between “collateral damage” and “terrorism” requires looking at the objective facts through the prism of a belief system that sanctions one but not the other.
Canberra, Australia
Can violence be treated as disease?
Premeditated murder of all stripes is, at its deepest roots, made possible by the failure to suppress what dog trainers call a “prey drive”. I see this as a primal reflex, held in check through social recognition, the most basic and essential form of associative learning. It is social recognition that allows us to see “other as kin”, neurobiologically bonding mothers and babies, lovers, and extended families.
This top-down neural social boost has resulted in the hyper-cooperative human societies that have been our most successful evolutionary strategy. But it also leaves us vulnerable to cultural manipulation of who we see as kin. When our brains begin seeing “other as enemy”, neurochemical default inhibitions for murder are compromised. That is when people become prey.
Wittman, Maryland, US
<b>First class post</b>
Higher prices for soft drinks will create a black market: seedy dealers will cut their product
Mike Whitey is sceptical about a UK proposal to raise sugar prices (5 December, p 7).
Who shall teach the systems?
There seems to me to be a paradox in all this discussion of expert computer systems replacing professionals (21 November, p 42). All the expert knowledge in these systems will have been derived from human “experts”. But what happens after the human experts become redundant, and only the encapsulated knowledge remains? How will the computer systems be updated?
In my own field of engineering design, the really useful skill of an expert is to look at an engineering requirement and understand what is important and needs time and resources to address, and what is less important. How is a computer going to get experience of this? There is no body of text it can absorb to tell it what to do.
Great Shoddesden, Hampshire, UK
Computer says no: who loses?
Chris Baraniuk discusses computer algorithms that de-select job applicants (31 October, p 20). Such programs now form a significant part of our lives.
The measurements they purport to make and the actions they indicate are the subject of behavioural sciences. But where, for instance, is the science to justify how human resources departments choose keywords or patterns to track in applications? Where is the science to show that searching for specific words is an accurate and reliable predictor of future performance? In the end those who lose from such unproven tools are the employers as well as prospective employees.
Ingleton, Lancashire, UK
To detect lies, first know the truth
So we now have computers that can spot liars (7 November, p 22). How can we be sure? We are told that algorithms picked out truth tellers 75 per cent of the time 鈥� but what they “correctly identified” were those found guilty by juries.
Agreeing with a jury that someone is lying isn’t the same as proving they are lying. In the UK alone, just ask the Guildford Four, the Birmingham Six…
Edinburgh, UK
Mass produced bread intolerance?
Your article asking whether food is getting less nutritious reports suspicions that the Chorleywood bread-making method could be a cause of the increase in bouts of irritable bowel syndrome (17 October, p 32).
People with the condition often claim it is triggered by bread. I wonder whether the prevalence of the process might also explain at least some of the rather similar cases that are these days widely 鈥� and often incorrectly 鈥� diagnosed as intolerance to gluten?
London, UK
Neural correlates of consciousness
In your story “Consciousness theory rocked”, you report that a proposed neural correlate to consciousness, the P3b EEG signal, can accompany unconscious as well as conscious brain processes (7 November, p 14). But this does not actually undermine global neuronal workspace theory.
I’m not sure anyone expects to find a single neural correlate to consciousness that is both necessary and sufficient for conscious processing to occur; that would be far too simple.
The evidence now tells us that the processes that generate the P3b signal are necessary but not sufficient. That actually represents potential progress in the theory, not damage to it.
Watertown, Massachusetts, US
Schizophrenia, cats and inflammation
You report research linking schizophrenia to brain inflammation and more active immune cells in the brain (24 October, p 17). Could this high level of immune cell activity be linked to the Toxoplasma gondii parasite, commonly transmitted by cats? This has been linked to schizophrenia (30 May, p 42).
I hypothesise that this parasite, which is thought to be found in between 30 and 50 per cent of the population, could be the trigger for the raised activity levels in the immune cells of those affected and is worthy of investigation.
Bridgwater, Somerset, UK
Have stored sperm, will travel
I’ve for much of my life and I found the snippet about these amazing arachnids using bats as transport most interesting (14 November, p 17). Hitch-hiking is common in several pseudoscorpion families. It can associate species with temporary or transient habitats, including nests, decaying trees, manure and compost heaps and bees’ nests. Females are the most frequently found travellers.
They have well-developed spermathecae, which store sperm for prolonged periods. On reaching a fresh habitat, they can produce a new population without having males around.
Hurstpierpoint, West Sussex, UK
Coo for the pigeons' union
Thank you for your report on pigeons diagnosing breast cancer (21 November, p 12). Much was made of employing pigeons to spot downed pilots in the ocean and at least one was granted, in 1981. I also recall reading about pigeons selecting faulty cigarettes. They are always good for a news item. They need a union and proper reward.
Northlew, Devon, UK
Water, water, everywhere
You tracked the trajectory of a water molecule from a crashed comet to being printed on your magazine (14 November, p 30). As water is a molecule, not an element, when it is in liquid form, it can and does dissociate into OH- and H3O+ ions; then it swiftly reassociates, but with different atoms. What is the half-life of an individual water molecule, in pH 7 solution at room temperature?
San Francisco, California, US
<b>Go fast and multiply</b>
You state that calculating the product of two numbers, each having n digits, requires about n2 steps (21 November, p 11). But while this is true for basic multiplication, that for large numbers take on the order of n(log n)(log log n) steps. There are algorithms that are even better for very large numbers. It isn’t known what the true complexity is.
Les Essarts-le-Roi, France
<b>For the record</b>
鈥� William Kirby’s letter about siting nuclear plants by the sea should have referred to our being committed in 20 years’ time to the risk of catastrophic sea level rises in a century or more (28 November).
鈥� Watt’s that? The is 0.3 watt-hours or 1000 joules (7 November, p 44)
鈥� It was in 1844 that historians proposed that the Black Death was a flea-borne bacterial disease; and the correspondence suggesting its use in the siege of Heraklion ended in 1651 (28 November, p 15).