What makes a lightning bug light up? And why do they only come out at night? — Rachel of Ozark, MO

Dear Rachel,

Those are interesting questions. Lightning bugs (also called fireflies) are little beetles that carry their own "flashlights." God gave these insects a special chemical that they store in their abdomens. When that chemical comes into contact with oxygen from air, which the beetle breathes, it gives off a bright flash of light. The process is called bioluminescence (bye-oh-LOO-meh-NESS-sense). This light helps lightning bugs find their mates. The male flashes his light first; when the female sees it, she flashes her light. This tells the male where she is. Lightning bugs, like many of God's curious creatures, are "nocturnal," which means they are active at night. If they were active in the daytime, the Lord would not have needed to give them a flashlight!