I’m blaming my fellow diarist Kate Blincoe. Recently, she extolled the joys of a UV torch, on the strength of which I bought one, have become addicted and now see the world entirely anew.
Ultraviolet is a shortwave, high-energy light normally undetectable to the human eye, but it is also damaging to many life forms. In the late Proterozoic ,most life flourished only under the sea, until the protective UV shield – the ozone layer – formed, 15km to 30km above our heads.
