Scientists in Germany have succeeded to genetically modify fruit fly larvae allowing them to smell blue light. The research team can activate single receptor neurons out of 28 olfactory neurons in the larvae for this sensory perception. Normally animals avoid light. However, blue light simulates in genetically modified larvae the smell of an odorant, e.g., banana, marzipan or glue -- odors which are all present in rotting fruit and attractive to fruit fly larvae.