Humane execution and the fear of the tumbril (3)
I welcome trials of the stunning of chickens using low oxygen levels, which lead to death with no warning. It is incomprehensible, though, that the UK Home Office for the killing of certain laboratory animals. This is a cruel method since it triggers gasping, a feeling of suffocation and panic. Perhaps civil servants should be asked to try a lungful of CO2 to see if they would still advocate its use for humane killing.
For the record – 10 March 2018
• The team refining the mass of the proton measured a property of this subatomic particle called the cyclotron frequency (13 January, p 7).
Might we have proof of a quantised God or gods?
Terry Klumpp shows us that Epicurus had an understanding of God that was well ahead of his time (Letters, 3 February). She or He can be seen to be both able and unable, and willing and unwilling to prevent evil – would that be a quantum God, perhaps?
The shipping forecast: old ships may sink
Joshua Howgego asks why ore carrier ships are sinking (27 January, p 34). Some of the more ethical mining and oil companies insist that their cargoes be carried by ships that are less than 10 years old. Old oil tankers converted to bulk commodities carriers seem to have the habit of sinking that Howgego describes.
Cloning credit needed for Dolly the Scottish sheep
I bought a subscription to 快猫短视频 for my husband, never having read it myself. Now, each week I will him to finish reading so I can devour it. I love it and am engaging my daughter with it. I am disappointed, however, with your mentions of Dolly the sheep in three articles over two weeks (27 January, p 3 and p 4, and 3 February, p 24). Not once did you credit the , nor the University of Edinburgh. Don't assume everyone knows where Dolly was made. Do acknowledge those scientists in Scotland.
The yet deeper roots of environmental struggle
Guy Cox reminds us about concern for the environment in the 1960s (Letters, 3 February). The environmental movement goes back far further than that. The world's first national park, Yellowstone, , and Australia's Royal National Park followed in 1879.
In the UK, Emily Williamson and Eliza Phillips, both opposed to the slaughter of birds for feathers to adorn women's hats, in 1891, leading to the Royal Society for the Protection of Birds.
The relative risks of Everest and rockets (3)
US and European astronauts at least are employees of civilian agencies that have “duties of care” to reduce the hazards of that employment. Everest climbers impose risks upon themselves. The question for them is about their employees: the professional mountaineers called “guides” if Western and “Sherpas” if Nepali or Tibetan in origin. So rich and mostly white people have one set of rules and poor local people a different set. Given the supposed egalitarianism of climbing culture, this is very awkward.
The relative risks of Everest and rockets (2)
How we perceive risk depends on how much control we have. Imagine climbing a tree. Now imagine climbing a tree with a headset, being instructed what handholds to take.
Which is more daring?
The relative risks of Everest and rockets (1)
Danielle Young says Everest climbers are more daring than astronauts (Letters, 3 February). But she compares the fatality rate NASA tolerates with the actual death rate for climbers. The two figures have nothing in common.
Symbiosis is ubiquitous and perhaps inevitable
Eric Wynter describes the internalisation of bacteria into proto-eukaryotes to become mitochondria as being “more unlikely, perhaps, than the appearance of life itself” (Letters, 3 February). But this is just one example of such symbiosis. Another is photosynthetic bacteria being ingested to form chloroplasts, which happened several times, giving rise to different lineages of algae.
Some scientists that cilia, such as those that remove mucus from our lungs, and flagella, such as those that enable sperm to swim, had a symbiotic origin, too. Symbiosis can be seen as inevitable.
Editor's pick: Sundry solutions to stop sand slipping through our fingers (1)
As an architect, I was dismayed to learn that the right sort of sand is another diminishing, non-renewable raw material (17 February, p 35). I had no idea this was the case. My reaction is to campaign for millions more trees to be grown and for there to be more research and development into wood and wood products, their durability, fireproofing, maintenance and so on.
In the meantime, it seems we have to look again at traditional, modern and future materials and ask what is the most sustainable combination for a particular context.
Humane execution and the fear of the tumbril (2)
I am glad that scientific attention is being directed at finding the kindest way to kill chickens. But I have a question. During the French Revolution, the guillotine was adopted to kill painlessly. But physical pain is only one factor: the emotional torment as the tumbril trundled to the killing site must have been horrific. Having cared for chickens, I have seen that sudden changes in circumstances upset them. Are those organising painless killing emotionally aware?
Humane execution and the fear of the tumbril (1)
You report on low atmospheric pressure stunning as a more humane method of slaughtering chickens (3 February, p 8). As a medical student in 1968, I was instructed in the physiological consequences of hypoxia and allowed to experience it by breathing through a carbon dioxide-absorbing canister.
I can honestly describe the onset of profound hypoxia as an enjoyable event. It was only the presence of fellow students, who forcefully separated me from the apparatus, that prevented me coming to an untimely end.
Gregg DuPont refers to the use of barbiturate drugs for the humane euthanasia of pets (Letters, 20 January). Surely hypoxia must be the most humane way of inducing death?
First class post – 10 March 2018
Trigger warnings stop flashbacks of sexual assault, so I don't nosedive into depression… Who drank all the coffee? why such warnings are in fact useful, not censorship ()
Plant communication has even more to tell us (3)
It is a sad irony that at the same time as Zaraska notes the value of urban trees in dealing with pollutants, a council contractor in Sheffield, UK, is busy cutting down hundreds of trees in the city streets. This is in spite of vigorous protests by its citizens.
Plant communication has even more to tell us (2)
It is interesting that plants communicate chemically, but your use of “word” and “sentence” metaphors is misleading. Plants may combine different chemicals to mean different things, but there is no plant analogue to the way we combine words to make sentences. Each chemical combination has only a stand-alone meaning.
The sentence metaphor would be valid if one chemical meant “attack” and it could be combined variously with others that meant “cutworm”, “aphid” and so on to yield combinations with derivable meanings like “cutworm attack”. As far as I know, that property, known as compositionality, has developed in only one biological communication system – ours.
Plant communication has even more to tell us (1)
Marta Zaraska describes worrying evidence of common air pollutants disrupting chemical communication in plants (17 February, p 32). She suggests this may also be implicated in the decline of pollinating insects, if they are finding it harder to locate flowers as a result.
This raises another troubling possibility. Many insects rely on chemical signals to attract mates. If these pheromones are similarly broken down in the presence of ozone and nitrogen oxides, this could also seriously hit population levels.
Monitoring of moths in the UK has shown that many species have declined substantially over the past 50 years. Might disruption of pheromone communication be a factor in this, alongside habitat degradation, pesticide use and light pollution?
Editor's pick: Sundry solutions to stop sand slipping through our fingers (3)
Easily available alluvial sand and gravel reserves may be running out, but the situation can be easily managed. There are simpler alternatives than high-tech remedies, although they need planning and the right investment decisions.
The Verney Report on aggregate supplies to south-east England to the same problem in 1976. These have stood the test of time. We now use less aggregates as building projects have been redesigned with lean construction principles. We use more recycled materials: around 90 per cent of construction and demolition waste is already recycled in the UK. We excavate marine aggregates from around our shores sustainably.
Editor's pick: Sundry solutions to stop sand slipping through our fingers (2)
A simple way to use less sand would be to reuse buildings instead of demolishing and “redeveloping” them. Here in Bristol, for example, the recent construction of a hospital involved knocking down about £60 million worth of buildings that were less than 20 years old, some less than 10 years old. Reusing them would have saved a great deal of sand and carbon dioxide emissions, not to mention money.