US scientists have created the first glowing butterfly by inserting jellyfish genes into its DNA.The genetically modified African butterfly glows luminous green in the dark, reports the BBC.The research is published in the Royal Society journal Biology Letters.The researchers used a technique called germ-line transformation to insert a marker gene that codes for the green fluorescent protein that make jellyfish fluorescent.By inserting the marker gene into the eggs of the African butterfly Bicyclus anynana, they created mutant butterflies.Dr Antonia Monteiro, of the State University of New York, said it was part of a project to understand how wing patterns emerged."We want to know how the colours and patterns were expressed in those places in the first place," he said."It's up to sexual selection, predator interaction, thermoregulation. There's all kinds of environmental factors that eventually determine which pattern is better for the species."