When it comes to primal symbiosis, plants rule
It was interesting to learn of a suspected archaeal host responsible for its primal symbiosis with an aerobic bacterium. The theory of endosymbiosis for eukaryotic cell origins, controversially proposed by Lynn Margulis in 1967, now has ample support with the detection of complex nucleic acids and protein synthesis within today’s mitochondria and chloroplasts(17 May, p 8).
Plant cells then got a double whammy of “modular evolution” when a proto-eukaryote, already with aerobic bacteria, subsequently acquired photosynthetic bacteria via endosymbiosis. Their putative descendants 鈥� the chloroplasts 鈥� have DNA homology with modern cyanobacteria (“blue-green algae”). We must, therefore, humbly conclude that the eukaryotic plant cell has an evolutionary “one-up” on those of us composed merely of animal cells.
Pretty happy with the emotions coverage (1)
I would like to share my method for addressing the emotional states of anxiety and unhappiness. Make a list of what is worrying you in one column. Then think of possible solutions and put these in the second column. Then work on how to achieve these(10 May, p 30).
It is important to physically write this on paper as, if you can’t think of a solution, you cross the worry out firmly and then tell yourself to forget it as there is nothing you can do.
Pretty happy with the emotions coverage (2)
Your look at emotions and their impact on us was excellent. However, it is worth raising the issue of where, in my view, they come from. I believe we inherit them from our parents, and they from their parents; no one sat us down to explain how we will feel about any situation we find ourselves in 鈥� the feeling of guilt or happiness, for example.
Reservoir's plight could be a gardener's delight
The image of Woodhead Reservoir in Derbyshire, UK, made me wonder about possible uses for all that newly exposed, dried-up sediment that has been slowly filling the reservoir and reducing its capacity. Much of this stuff is good-quality soil biomass that is free or mostly free of artificial fertiliser, herbicides and insecticides. I would be delighted to have some on my garden(17 May, p 7).
Quantum gravity: my take on this conundrum
The energy applied by some of the world’s great minds to understand quantum gravity is something to celebrate, but the lack of any real progress in over 100 years implies a gap in the thought process(17 May, p 30).
A tenet of quantum mechanics is that the wave function of a quantum particle collapses when the particle interacts with its environment. My hypothesis is that “quantum gravity” is such an environmental interaction between a quantum particle and a massive object. That interaction may be as mundane as a photon emitted by the massive object and absorbed by the particle. It causes the wave function of the particle to collapse at the point of the interaction, which will be within the volume initially occupied by the wave function. Furthermore, it can be shown that the probability function representing the location of the interaction is concentrated towards the massive object. So, the particle establishes its new wave function, now centred on the point of the collapse. The shift in the wave function’s centre represents an acceleration by the particle towards the massive object, which we recognise as gravity.
Are microplastics making us blas茅 about threats?
You report that ingestion of microplastics by mice changes their behaviour in the face of a deadly corn snake. After being given food contaminated with plastic, they failed to treat the snake as a threat(10 May, p 38). Would it be too cynical to speculate that the lack of concern over the past 40 years by humans in the face of obvious climate and ecological collapse may be due to exposure to plastics?
Extracting buried hydrogen isn't green
The possibility of geologic hydrogen reserves in mountain ranges is very interesting. But Frank Zwaan saying that these or any other fossil hydrogen sources are “like a free green energy source” is naive at best. Drilling for hydrogen is neither renewable nor without substantial operational and environmental cost(17 May, p 14).
Fossil hydrogen would be better than fossil petrochemicals to use as fuel where other stored energy isn’t practical, such as for aviation. However, it would be much more sustainable to generate hydrogen from clean electricity and water.
Love the idea of seeing through another's eyes
Rowan Hooper’s Future Chronicles instalment “Through their eyes” reminded me of the 1967 novel Night Walk by the Irish science fiction writer Bob Shaw. In this tale, the blind hero designs a device in the form of a pair of spectacles that transmit the signals in the optic nerves of nearby animals into his brain so that he can literally see through their eyes(10 May, p 22).
When a Dyson sphere goes supernova
A solid Dyson sphere built around a star to capture all its power would be unstable, just like one made of many satellites. Even a rigid sphere with its star perfectly centred would experience gradual drift, necessitating occasional corrections, which might be visible as bursts of radiation. Without such correction, it would eventually intersect with its star, to end with a bang(17 May, p 10).
A big number to match string theory (1)
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A big number to match string theory (2)
Jon Cartwright points out “that string theory was so flexible it could describe a truly vast array of fantastical universes. Something like 10500 in fact 鈥� a number so huge it belied any physical comparison”. I recommend taking a look at protein folding, in which there are reportedly 10500 potential folding possibilities.