Letters archive

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) …

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 …

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 …

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.

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 …

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 ).

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 …

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 …

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 …

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 …

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.