There is no easy way to tackle the obesity epidemic
Obesity is worryingly omnipresent in some countries and is, in my opinion, unlikely to be significantly abated by the use of drugs. Education and changes in attitude are long, slow roads to correction in society, but are utterly necessary to crack this problem. As demonstrated by the spectacularly unsuccessful dieting route to long-term weight loss, there will be no quick, sustainable fix (15 July, p 32).
Moon's hot zone could have been nuclear reactor
You report on the mystery of a radioactive zone beneath the moon’s surface in the Compton-Belkovitch area (15 July, p 13).
Evidence of past natural uranium nuclear reactors, moderated by water, has been found in Gabon. On the moon 3.5 billion years ago, when the last eruption of the volcano in that area took place, the amount of uranium-235 would have been greater, meaning a natural nuclear reactor would have been possible.
Water is needed as a moderator in natural uranium reactors and in modern thorium reactors, so if the above is correct, then further evidence is supplied for the presence of water on the moon.
Did I jokingly resolve a big problem in physics?
I should state right at the outset that I am no physicist. I am a retired journalist and the written and spoken word is my area of expertise. But I read 快猫短视频 because I am a science nut (8 July, p 30).
So, I was amazed when I read Heinrich P盲s’s feature “Reality reconstructed”, particularly the line where he said string theory researchers are suggesting that gravity may be entanglement in disguise. At the end of March, in an email to a friend, I jokingly wrote that gravity could be spooky action at a distance. The text of the email is included below to give you its layman’s flavour.
“My take on general relativity [GR] goes thus: if you travel extremely fast, your watch slows down and may even stop. And we have spacetime because it takes time to travel through space. And gravity is spooky action at a distance, not just a distortion of spacetime. I might just have cracked the missing link between GR and quantum physics with that last bit!”
It isn't just AI 鈥� new tech is always disruptive
Almost every new technology has been met with disbelief, dismissal and doomsaying. But I have yet to read a cogent argument that the social impact of AI available now and in the near future will amount to much more than that of the steam loom or computer (Letters, 15 July).
Yes, there will be economic sectors that will see severe disruption: this also happened with electrification and, more recently, with computerisation. In the same way that we need to have a rigorously planned transition to an economy free of fossil fuels, we must develop informed and thoughtful plans for adapting economies to the possibilities that may arise from developments in AI technologies.
To strengthen breathing, just blow into a shawm
I loved “Cheat your way to better health”, but when it came to E. Fiona Bailey’s experiments with the Powerbreathe device, I wondered if she had considered the breathing exercise provided by playing a wind instrument. Brass and reed instruments in particular demand not only great breath control, but high-intensity “resistance training” for the diaphragm and ab muscles 鈥� a lot more than five sets of six breaths, too. As a shawm player, I have personal experience of this (1 July, p 40).
We have lost touch with our wider microbiome
You suggest that industrialisation and diet may influence the human gut microbiome. I suspect that a more important factor is our alienation from nature (1 July, p 17).
Apparent similarities between the human gut microbiome and that of the soil suggest to me the two are part of the same system. For almost all of human existence, there has been a direct connection between the gut and the soil. Our ancestors would have eaten food without systematically cleaning it, so would have been “contaminated” with soil microbes. Defecation would have returned gut microbes directly to the soil, rather than waste being carried away by modern sewerage systems.
In this way, our gut microbiota would have been constantly refreshed with microbes from the soil and vice versa. This cycle has now been broken, and our gut microbiome is affected by antibiotics and excessive hygiene, without the constant replenishment that contact with soil would bring.
No doubt about it, animals are expressing emotions
Your article on animal feelings suggests anthropocentrism could lead us to imbue animals with emotion. When an elephant in a circus screams while being beaten, only a Cartesian would fail to see that she is expressing emotion. So, too, when a cow chases the truck in which her calf is being taken away and when macaques shake the bars of their laboratory cages (8 July, p 34).
Fear, joy, love, grief and the desire to stay alive aren’t human traits, but rather shared ones 鈥� or we wouldn’t have experiments on animals that depend on acknowledging them. As for farmers considering improving animal welfare, let’s just stop eating our fellow Earthlings.
Producing meat in plants seems a much better bet
I have always believed that genetically engineering plants to produce analogues of animal-sourced protein is going to be far more viable than trying to grow actual animal tissue (8 July, p 17).
Culturing tissue requires a huge variety of nutrients (many of them currently sourced from animals) and has to be carried out in an ultra-sterile environment.
For the record
The tusks of male stink bugs in Tjaltjraak Boodja Park, Australia, are merely unusual (24 June, p 7).