Ideas on the meaning of cave art hand stencils (1)
You report that prehistoric hand stencils on cave walls with various digits missing could represent a sign language. I am a computer scientist, not a linguist, so I have a different take on the matter(18 March, p 38).
It looks to me like the 10 different hand signs (out of a possible 32) seen in Gargas cave in France are a way of efficiently counting to a number greater than 5 with one hand, for example when the other hand is occupied holding a spear or some other type of weapon. They may represent 1 to 10, or possibly even larger numbers.
Ideas on the meaning of cave art hand stencils (2)
The cave stencils look like tic-tac hand signals used by bookmakers to communicate betting odds at race courses to me. Perhaps they were valuable when out hunting. My granddaughter learned sign language before she could talk, and the recent television series Chris Packham’s Animal Einsteins showed hand gestures that were identical among chimps, bonobos and human toddlers. It isn’t so surprising that early humans communicated with sign language and recorded it on cave walls.
Ideas on the meaning of cave art hand stencils (3)
No right hands are shown in the illustrations or photos in your story, leading me to believe all the cave stencils are of left hands.
As a left-handed person, I wonder if any of the stencil-makers were left-handed and, if so, why they didn’t stencil their right hands. In addition, if these did represent a form of sign language, was it a left-hand only language, with the right hand reserved for, perhaps, holding a weapon while communicating?
Ideas on the meaning of cave art hand stencils (4)
The hands could represent signals used while hunting animals, as suggested, but perhaps we are seeing an early classroom, and the stencilled wall is a blackboard to teach youngsters which gesture corresponds to each animal.
Is Venus volcano a sign of planetary nuclear activity?
Recent evidence of volcanism on Venus could be due to the continuing, very slow fission of uranium and the decay of its various daughter products, the result of an earlier, natural nuclear reaction deep underground. Similar natural reactors have been found on Earth close to the surface in Oklo in Gabon. If this is the case, it also supplies evidence for the existence of water on Venus, as water is required to moderate any sustained chain reaction(25 March, p 20).
Great to get some advice on longer-term thinking
I greatly welcomed Richard Fisher’s article on far-sighted thinking for its clear explanation of why most governments of high-income countries have failed to tackle climate change, and also for its pointers on how to adopt a long-term mindset(25 March, p 46).
It isn't just humans that block the flow of rivers
In Graham Lawton’s excellent summary of the state of British rivers, the issue of fragmentation by dams and other obstacles is mentioned, and it is stated that the defining characteristic of natural rivers is that they flow. I wonder if this is entirely true. I estimate that the population of beavers in the UK in prehistoric times must have been about a million. They would have built far more than the 50,000 human barriers quoted in the article(25 March, p 42 (UK edition)).
One solution to light pollution for stargazing
Your article made me ponder the light pollution that spoils our view of the night sky. I can see well in the dark without light to blind me and I get around fine in the woods at night without artificial light. However, if there is even a peripheral passing of white light, it will take my night vision a few minutes to recover(4 March, p 51).
On a continuous, 300-kilometre hike, my headlamp had white, red, blue and green beams. The blue light was disorienting and I never used it, while the red was so negligible that I could find what I needed without it.
The green beam provided me with ample light over a broad range and, vitally, it didn’t destroy my night vision. Something as simple as replacing street lights with green bulbs could reduce light pollution for stargazing.
Chris Packham is right, but how do we get there?
Chris Packham’s article should be applauded for its clear statement of the obvious: a need to achieve a sustainable human population in balance with the available renewable resources(25 March, p 27).
The problem is that he, like most commentators, provides no advice on how this can actually be achieved on the scale or in the timescale necessary. It is going to take more than a few thousand or hundreds of thousands of people attempting to cut back on their carbon footprint to get anywhere near a sustainable planet.
The depressing and the most likely outcome is the occurrence of catastrophic events that drastically reduce our species’ ability to consume as much as at present, followed by a complete shift in the way we organise to exist and consume.
On the pros and cons of video games for kids (1)
Naomi Fisher describes how video games enriched her children’s lives and how she bonded with them over shared gaming experiences. As a parent and avid childhood gamer, I agree that it can be a very positive experience. I am suspicious of any wholly negative coverage of gaming, which can border on snobbery(18 March, p 27).
However, it is important to acknowledge that hours spent playing computer games can seriously disrupt the doing of homework. Gaming can be addictive and excessive gaming comes with an opportunity cost.
On the pros and cons of video games for kids (2)
I am forced to side with Fisher in her view that we should take a more positive approach to video games among children, especially when my grandson told me recently that he earned points in a history lesson with his knowledge of Vikings and ancient Greece gained by playing such games.