Smart Moths Have Evolved to Fly Away From City Lights

Everyone knows that moths love light. But what you love can kill you, as proven by the millions of flying insects that immolate themselves on hot lights, or are gobbled up by predators in well-illuminated environments.

For that reason, some moths have evolved to avoid artificial lights, according to new research from Swiss zoologists. Researchers trekked around Basel collecting thousands of young, small ermine moths from dark areas (villages) and ones bathed in light pollution (cities). They then raised the bugs into adulthood and tested their reactions to light. The result: Moths descended from generations in heavily lit places tended to avoid human light, or as their study in Biology Letters phrases it, showed a “significant reduction in the flight-to-light behaviour.”