Once upon a time there were two moths: a moth that lived in town and a moth that lived in the country. These moths had a problem; you see, all moths are attracted to light, and this fatal attraction was causing the deaths of thousands of their kind. You have probably seen them fluttering around the lamp on your porch or bumping into your flashlight when you walk outside in the dark. Unfortunately, their problem kept getting worse. As cities grew, so did their light pollution, and the moths found that more light meant more moths dying. The country moth was used to the peaceful darkness of the countryside, so she could avoid the dangers of fluorescent bulbs most of the time, but when she saw the glow of a lamp she could not resist flying right towards it. However, the town moth was surrounded by lights that never went out. The glow of street lamps, neon signs, and all-night businesses never allowed the town moth the darkness of the sparsely inhabited countryside. So she had to adapt, to evolve, and the town moth started to learn to stay away from the light. In fact, a new study has shown that moths raised in areas with large amounts of light pollution show a 30% reduction in their “flight-to-light” behavior. The scientists collected a large sample of moths of the same species from dark areas and areas with high light pollution, and then tested their behavior when released in a cage with a fluorescent bulb. The pronounced decrease in the number of moths flying to the light observed in the individuals from inhabited areas suggests that they have evolved in order to cope with the ever-growing problem of light pollution.
Want to learn more? Visit https://www.sciencemag.org/news/2016/04/moths-evolve-avoid-lights
May 4, 2016