¡¡¡¡Many animals migrate at certain times of the year for a variety of reasons. One of the most breathtaking migrations is the annual movement of the monarch butterfly. It uses its eyes to measure the position of the sun£¬ which allows it todetermine the way to go.

¡¡¡¡The solution to the mystery of the butterfly’samazing ability comes at a time when its population has crashed by as much as 90 per cent in the last few years. In many places where the creature can be found£¬ people are destroying the natural environment by cutting downtrees and using chemicals that kill the plants that monarch caterpillars eat. Fortunately£¬ people have worked together toseek for ways to protect the butterflies and the population is recovering bit by bit eventually. After all£¬ the more we concentrate on the butterflies£¬ the greater the chance they willsurvive.