6. Firefly
Found in moderate, subtropical and tropical climates in most parts of the world, the Firefly is a family of winged insects made up of some 2,000 species. All of them share an ability known as bioluminescence that has fascinated humans for millennia. Yet, it was not until recently when scientists finally figured out the actual chemical reactions that produce this insect’s yellow, green, orange, and even blue glow.
