If life does exist on Venus, we must be very careful
As medical microbiologists, we find the possibility of microbes on Venus tantalising (19 September, p 7). After all, our speciality could be on the verge of becoming an interplanetary discipline.
Though the existence of Venusian microbes remains improbable, it is worth pausing to consider the risks inherent in the next step of this scientific endeavour, the possible collection of Venusian atmospheric material to examine for evidence of microbial life.
We should proceed with utmost caution and within a robust regulatory framework that would constrain the whims of impulsive space capitalists or competing nation states. Currently, high-risk terrestrial pathogens are handled in specialist labs that are isolated from nearby communities and have sophisticated security. Governments accredit the labs according to international standards.
Were we to obtain samples of Venusian origin, it would be incumbent on us to create something even more secure: labs in which all sample analysis is done away from Earth, whether on purpose-built space stations or in lunar or Martian research facilities.
We may well encounter a microbial organism that is utterly unlike any pathogen we know, with incubation periods, dormancy capabilities and transmission dynamics distinct from our terrestrial experience so far.
Some of us can tell people apart by how they walk (1)
I read your article on using gait to identify people with great interest (19 September, p 36). I am prosopagnosic, or face-blind, along with up to . Some prosopagnosics have been using gait and posture to help us identify people for pretty much all of our lives.
Your article says that gait recognition requires a huge amount of computing power. Maybe law enforcement agencies could employ prosopagnosics alongside or instead of computerised systems?
Some of us can tell people apart by how they walk (2)
Monty Python’s Ministry of Silly Walks was ahead of its time in promoting countermeasures to gait analysis. The masked man hirpling down The Strand isn’t necessarily the Lord moving in mysterious ways, but a concerned citizen who wishes to remain anonymous.
Death toll shows the chaos virus has unleashed on us (1)
Your article on the global coronavirus toll as it neared 1 million deaths shed light on the chaos endured by human beings this year (19 September, p 10).
But the information from the authorities has been conflicting, not least in the UK. The answer to your question “Can we trust the numbers?” seems to be no.
Since the UK government changed the definition of a death from covid-19 to one that occurs within 28 days of a positive test, the picture has become more blurred. At the time of writing this letter, the number of deaths in the UK from covid-19 is just under 42,000, but the number of excess deaths calculated from the UK average death rate over five years is at least 70,000 since mid-March.
Meanwhile, the death figures in Russia and China seem suspiciously low, but that is another matter.
Death toll shows the chaos virus has unleashed on us (2)
The figure of 1 million global deaths needs to be put into context. It is about 0.015 per cent of the global population and is equivalent to those that malaria kills in 30 or so months 鈥� every 30 or so months.
Time to launch the fight back against unreason
After reading Graham Lawton’s worrying column about QAnon conspiracy theories, I suggest we adopt a “reality slogan” to fight back (19 September, p 24). In highlighting the inescapable fact of the laws of nature, physicist Richard Feynman came up with a good one in his report on the Challenger space shuttle disaster: “Nature cannot be fooled.”
A heap of sand isn't really so difficult to define
There is an answer to Eddy Keming Chen’s question, “how many grains of sand can you take away from the heap and still call it a heap?” (5 September, p 36)
“Heap” has a three-dimensional vibe as a noun, and especially as a verb. Three or fewer grains can form a layer at most, unless you are really good at balancing sand grains, and then it is a cairn. So, we get to the four that make a wee pyramid.
Yes, it would be a small heap, but so would Chen’s million-grain heap 鈥� at best some 180 layers of a triangular pyramid, a few hundred millimetres on each edge. Both insignificant on the cosmic scale.
Chen’s question is similar to “how many philosophers can you remove and still call it a department?” 鈥� an experiment some managers might threaten if the staff continue to spill sand in the tea room.
We may have to step in to do the job of wildlife
Plummeting wildlife populations, particularly of mammals and birds, must place the forests and savannahs of the world under increasing stress due to a lower rate of soil fertilisation by faeces and a lower rate of seed dispersal (26 September, p 16).
Considering the importance of forests and grasslands for carbon sequestration, it may become beneficial to take measures such as artificial fertilisation.
Look away if you don't like the sight of wealth in space
According to Abigail Beall’s Stargazing at home article, you can see Elon Musk’s SpaceX satellites with “a bit of luck” (19 September, p 51). If I looked up and found my view of the night sky polluted by the sight of a billionaire’s vanity project, I would consider it a misfortune.
Thanks for praising the merits of Darwin's theory
You brought a lump to my throat with your piece on the triumphs of evolutionary science, (26 September). At long last, a small victory in these unsettling times. I have often quoted the sentence, “The voices of evolution’s detractors have largely fallen silent, worn down by the patient drumbeat of reason.” Thank goodness and thank science.