Finding Fluorescence

Simon bought me a UV torch for my birthday. It arrived a couple of weeks ago and we've been madly checking the firewood before putting it in the stove, and fungi and lichen in the forest when we walk. 

 

This unidentified fungus on a chestnut firewood log looks white under daylight but fluoresces turquoise under UV light.

UV torches are the latest toy for naturalists. They can be used for looking at flowers, insects, scorpions, lichens or animal eyeshine at night. They are useful for geologists too, as some minerals fluoresce.

Humans can't see ultra violet light, but lots of animals such as insects and birds can. Somewhat to my surprise there is a whole project in iNaturalist, the global biodiversity monitoring citizen science website, on UV fluorescent organisms. 

Simon had to do lots of research to make sure he bought the right product. The right frequency (365 nm) is important. 

Once it gets a bit warmer and less wet we'll have to set up some experiments in the garden at night.