Monkeying around
Catherine Brahic writes that chimpanzees in Uganda have learned to use moss to sponge up drinking water after copying one innovative member of the group (4 October, p 9). She says that a decade ago it was believed only humans had the capacity to imitate in this way. But surely chimpanzees are known for this trait? A quick search of the internet reveals that “aping” has been used since the 1630s to mean imitation or mimicry.
Edale, Derbyshire, UK
For the record
鈥� We have got wind of an error in our story about polar influences on the jet stream (4 October, p 16): the Arctic melt peaks in September.
鈥� Status update: after recovering from his illness, Faustino the chimp rose back to beta male in his troop (11 October, p 28).
鈥� We came unstuck in our article on harvestmen’s glue-laced legs (11 October, p 19); the arachnids are in Opiliones, a different order to spiders.
Time warped
Searching through a pile of old 快猫短视频 magazines, I came across Peter Nowak’s article about smartphones and TVs with curved screens (31 May, p 24). In the first paragraph, he says that “rumours continue to swirl that even Apple’s forthcoming iPhone 6 will bend to the craze later this year”.
Given complaints about the tendency for the latest iPhone to bend in customer’s pockets, did Nowak know in late May something that Apple was not aware of? Or was this turn of phrase divine inspiration?
Athens, Greece
Meaningless lives
Nick Bostrom considers the challenge of preparing for artificial intelligence that is superior to us (5 July, p 26). Why would we want to build such a computer? Surely one of the ways we give meaning to our lives is by searching for new knowledge. If you could find out anything you wanted to know by typing a question in to a page on the internet, would there be any meaning to our lives any more?
The Lee, Buckinghamshire, UK
Change of tune
Further to Judith Wallace’s observations about sheep responding to her baby’s cry (11 October, p 35), I can add something of my own experience.
The land surrounding our cottage on the Isle of Skye is often used for grazing. Once when I was practising on the soprano saxophone, all of the pregnant ewes moved towards me to listen. At this stage they would not have known the exact sound and pitch of their unborn lambs’ bleats.
As I continued playing, they suddenly dispersed and I wondered whether I had upset them with my new tune.
But on looking up I saw that the Highland cattle had now arrived and were also responding to the music. With the sight of all the shaggy horned beasts moving toward me, discretion became the better part of valour: I abandoned my saxophone recital and sought shelter.
Redland, Bristol, UK
Pension extension
In Clare Wilson’s article on life-extending drugs (4 October, p 6), one consequence that wasn’t mentioned was the impact on pensions. At present, people work for about 40 years and survive for about a further 15.
If they were to live 10 years longer, that would be a 67 per cent increase in the length of time they were drawing a pension.
This would make existing pension funding arrangements unsustainable, and people would have to either make a substantial increase in their pension payments throughout their working lives, or spend most of their extra years working 鈥� and thereby becoming “job blockers” for the next generation.
High Peak, Derbyshire, UK
Upturned world
Laura Spinney explores the idea of enactivism 鈥� that thinking and feeling arise from how we see and interact with the world (11 October, p 42). This may help explain the difficulty some doctors have in learning to use an endoscope.
When using this device to perform a colonoscopy, a patient is placed on their side, and the doctor inserts the endoscope.
The progress of the scope is not determined by looking directly at the patient, but rather, counter-intuitively, by monitoring an image on screen.
Junior doctors often struggle to make sense of what they see on the screen, because the image can be upside down and back to front at different times. The enactivist explanation could be that doctors have to learn a new form of embodied know-how to use the endoscope.
They have to understand how their physical manipulation of the endoscope affects the image on the screen, rather than how it moves inside the patient.
This suggests that at least the initial part of training doctors in the use of endoscopes could be done using software, without the need to involve patients.
Hillsborough, County Down, UK
Material claims
The artwork accompanying your article on aerogels describes them as “solids lighter than air”, but this is not borne out by the text. If an aerogel or nanofoam-type material could be made into a spherical shell, capable of supporting an airtight covering against a pressure of one atmosphere, you would have the “holy grail” of lighter-than-air vehicles: a lifting body capable of containing a vacuum without excessive structural weight.
Jomtien, Thailand
Material claims
Biodegradable plastics are more ancient than you credit in your special report on wonder materials (11 October, p 36).
Modified cellulose has been researched much longer than “almost a century”. The first thermoplastic, Parkesine, was patented in 1856. The same modification, nitration, had already given us the artificial fibre rayon, first described in 1855.
Kenilworth, Warwickshire, UK
Multiple trade-offs
Rowan Hooper’s interesting feature on the multiverse (27 September, p 32) has left me confused and distressed. If I believe in the multiverse, every time something annoying happens to me such as missing a train or stubbing my toe, am I to blame the luckier version of me in another universe?
Also being a good, caring and honest person, should I instead be more selfish, rude and deceitful to give the wives of my multiverse selves a break?
Newport Pagnell, Buckinghamshire, UK
Small print
In her article on the future of 3D printing, Aviva Rutkin suggests that cost and difficulty of use are dissuading businesses and individuals from purchasing printers (4 October, p 22). But the cost of the cheapest 3D printers is no more than that of a desktop computer or a photocopier.
Arguably the usefulness of plastic on its own is a far greater contributing issue. Besides artwork and knick-knacks, how many of the items we use on a regular basis are made entirely from plastic? I can’t think of any I would require on a regular basis.
Maybe in a futuristic world of printing by nanofactories, their usefulness would be sufficient to produce demand on a more significant scale, but until then, we have 3D printers that rarely provide more than entertainment value, and will continue to be novelty devices.
Shotatton, Shropshire, UK
Tied up in knots
Leonie Mueck writes that the stability of knots in light and liquid crystals “makes them promising candidates for creating a long-term, durable way of storing information”. They are not the only candidates for this. The ancient Incas had quipus, knotted strings that were used to record everything from taxes to calendar dates.
Apparently the Incas also encountered some of the problems identified by Mueck, such as multiple interpretations of one knot. As they say, there’s nothing new under the sun.
Winnipeg, Manitoba, Canada
Tied up in knots
I read with interest Leonie Mueck’s article on creating and studying knots in various physical systems (4 October, p 42). This included the work of the groups of William Irvine and Slobodan Zumer as well as my own.
However, I feel I should point out that our 2010 paper on creating optical knots was predated by theoretical work by Michael Berry and me in 2001, followed by experiments by the group of Miles Padgett in Glasgow in 2004. Our 2010 paper (Nature Physics, ), a collaboration again with Padgett’s group, built on and significantly widened this earlier theoretical and experimental work on knotting light, and in fact demonstrated conclusively that knotted lines of darkness can exist in laser beams, without requiring further digital enhancement as suggested in Mueck’s article.
University of Bristol, UK
Scare of the dog
Helen Thompson’s article on uncovering the identity of an infant, “Little Albert”, who was conditioned to fear animals gives a fascinating insight into one of psychology’s murkier corners (4 October, p 10).
But given his reported fear of animals as an adult, if he was indeed William Albert Barger, am I alone in questioning the closing comment that suggests that his conditioning did relatively little harm in the long run? If academic psychologists don’t consider that a lifelong aversion to animals in someone conditioned as an infant to fear them constitutes long-term harm, then I for one would not wish them to be treating me or my loved ones.
Melton, Suffolk, UK
Multiple trade-offs
Surely decisions that hive off a new universe must ultimately derive from the sort of quantum event that decides the fate of Schr枚dinger’s cat, and are rare.
Free will aside, the choice of whether to tuck into a sticky bun, for example, will be based on whether you are hungry, gluttonous or sweet-toothed, but not on the random radioactive decay of one of your brain’s carbon-14 atoms.
A bit of metaphysical masturbation is healthy, but for those people locked in stasis, staring at a plum crumble and worrying about the effect on the diabetes of their multiversions if they scoff it, I say: get a grip!
Stirling, UK
Multiple trade-offs
It was courageous of Rowan Hooper to venture into the rarified atmosphere inhabited by quantum physicists and to interpret for the rest of us what at times can seem outright fruitloopery. However, I am left with a picture of theoretical physicist Don Page’s supposedly Christian God as some sort of megalomanic maths genius hell-bent on creating an “elegant” universe, amorally discounting the collateral damage inevitably done to the very creatures he created to inhabit a proliferating multiverse. In at least some of the strands of the multiverse we will have made the right decisions. While I am charmed at the notion of helping a god with his maths homework, I can’t help feeling that there is a flaw somewhere, whether it be in my analysis of the article, or in Page’s mindboggling rationalisation, or in Hooper’s attempts to simplify it all for non-mathematical dummies.
Blenheim, New Zealand
Multiple trade-offs
I read with great interest the article about the existence of the multiverse, but still find it rather difficult to believe. Since reading it, I have decided to toss a coin every day to decide whether to relieve myself at work or wait until I get home.
Does this mean that every time I toss that coin, a whole extra universe, with all those countless millions of planets, stars and galaxies, comes into being only to offer a place where the alternative outcome can exist? There must by now be several hundred universes out there, devoted solely to my toiletry decisions! Does this not seem unlikely to you?
Maidstone, Kent, UK