Asked by: Aaron Hacon, Norwich
There’s a nugget of truth behind ‘Red sky at night, shepherd’s delight’, because red sunsets are associated with settled high pressure systems that don’t wash all the dust out of the lower atmosphere, and high pressure tends to mean fine weather.
But it would be a stretch to say that our appreciation of sunsets is a genetic weather-forecasting mechanism. Rather, we have evolved an aesthetic sense as part of the wider analytical faculties of our brain. Far from being skin deep, ‘beauty’ is a shorthand way of measuring the fundamental ‘rightness’ of a thing. In people for example, the attributes we find beautiful generally correlate quite well with physical health or reproductive ability. Instead of evaluating all these different attributes independently, they all get rolled into a single measure: beauty.
The philosopher Dennis Dutton has suggested that the open rolling plains with occasional trees, that are so often represented in landscape art, are beautiful to us because they resemble the savanna of the Pleistocene epoch, when Homo erectus was first developing an aesthetic sense. Red sunsets would have been a familiar part of these landscapes and in an era when night was the most dangerous time, making sure you were safely back at camp to appreciate the last dying gasp of the day was probably especially important.
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.