Mark Leyner and Billy Goldberg wrote Why Do Men Fall Asleep After Sex?, a collection of “questions you’d only ask your doctor after your third whiskey sour.” Many of them are potentially embarrassing: What does a chimpanzee do with the umbilical cord after it has a baby? Can you breast-feed wih fake boobs? Is douching dangerous? Is there such a thing as a death erection? And some, like this one, respond to an everyday curiosity:
Why are bugs attracted to light?
Phototaxis is an organism’s automatic movement toward or away from light. Cockroaches are negatively phototactic. Turn on that kitchen light and off they scurry to their dark little holes. But many insects are positively phototactic – as evidenced by teh mass bug graves in your light fixtures. Many people are also phototactic, especially for the “limelight” – those of us who secretly crave the strobe fusillade of paparazzi flashbulbs and murmer, “Mr. DeMille, I’m ready for my close-up” in our dreams… But, back to bugs. There are a variety of reasons that various insects are positively phototactic. Many insects, including bees, orient themselves in relation to the sun. Certain nocturnal bugs – moths, for instance – use moonlight to navigate, flying at a certain angle to the moon’s light rays to maintain a straight trajectory. When it approaches a source closer than the moon – say, a lightbulb – a moth perceives the light as stronger in one eye than the other, causing one wing to beat faster, so it flies in a tightening spiral, ever closer the the light. Some bugs are sensitive to ultraviolet light reflected by flowers at night. Artificial lights that emit UV rays will also be attractive to these guys. Other bugs are drawn to the heat that incandescent bulbs produce at night. Fireflies are bugs and bulbs all in one. They use their bioluminescence to attract each other.