MOTHS WITH MAPS?

摘要

When migratory moths and butterflies emerge from their chrysalises in autumn in northern Europe, they immediately start flying south. When the next generation emerges on the Mediterranean coast the following spring, they start flying north. How do these creatures know where their breeding grounds are, when none of them lives to make the return trip?rnIt seems they don't. After the adults emerge, they simply travel in a hard-wired direction until they become sexually mature. How far an insect migrates depends on the length of this genetically determined phase. Migrants don't decide where to land based on the weather or the vegetation: they land when they reach the insect equivalent of puberty.