What do you usually do when a flying insect lands on your arm? Most likely you blow it away. But what if that bug were a ladybug (瓢虫)? Then chances are you would let it stay. What is it about ladybugs that we like?
Farmers once thought ladybugs were a good luck sign. A ladybug in the field meant that the crops (庄稼) would be successful and the weather would be good. The farmers may have been exaggerating (夸大) about what a very small bug can do, but in fact ladybugs do help out with the crops. They eat harmful insects.
Actually, it is not the adult ladybug that eats the other insects. It's the ladybug larvae (幼虫). Ladybugs lay their eggs on leaves that are covered with aphids or other insects. When the larvae come out of the eggs, they are very hungry and will eat mites, aphids, mealy bugs, green flies, and other crop-destroyers.
A single ladybug larva can eat over 1,000 aphids in one day. In the 1800s, ladybugs were brought all the way from Australia to California and set free among orange trees that were dying from being eaten by insects. The little red and black "eating machines" completely saved all the trees.
Ladybugs go about their daily business without worrying much about anything. Very few birds or insects will eat a ladybug because it gives off something that is dangerous to eat. Ladybugs also protect themselves by playing dead. They fall off leaves and remain very still until their enemy goes away.
So next time you see a ladybug, think about what it may be up to. Maybe it is off to save an orange tree. Maybe its next move will be to fall off a leaf and play dead or stand up to a bird about 100 times its size. Maybe it's letting you know that the weather will be good tomorrow. Who knows? Ladybugs are special that way.
