'Like moths to a flame'? Here's what's going on with insects and porch lights
Turn on a light outside at night, and it won't be long before a bevy of insects start careening wildly around it, apparently drawn in "like a moth to a flame," as the saying goes.
Now, in a series of studies that offer a new way of thinking about an old mystery, scientists say that insects do this because an artificial light can mess with their natural way of knowing what direction is "up" while flying.
Motion-capture videos of moths and other insects show that they seem to instinctively turn their backs to light, and try to fly so that their back is always facing the light source, according to a new report in the journal Nature Communications.
That habit makes sense in a dark, natural setting such as a forest because there, the star-strewn sky is typically the brightest source of light, the researchers say. Any insect that's been swooping around in all directions through the air can reorient itself by pointing its back towards this light.
"You can use that to work out which way is 'up' really, really fast, which is as important for insects as it, who studies insect flight at Imperial College London.
