A female monarch lays her eggs. She lays them one at a time. She lays them on milkweed leaves. A monarch egg hatches after a few days. It is usually about four. A monarch caterpillar eats and grows for about two weeks. It does this before it makes a chrysalis.

Monarch caterpillars eat milkweed. Milkweed is poison to most animals. The poison stays in the monarch's body. It makes the monarch taste bad. A monarch has bright colors. They warn birds that it tastes bad. A monarch caterpillar has yellow, black and white stripes.

Many caterpillars hang upside down. They hang from a button of silk. They do this just before they become a chrysalis. A monarch chrysalis is green. It has tiny gold dots. It is often hard to see. It blends in with its surroundings. A monarch stays inside it for about two weeks.

A butterfly has six legs. It has four wings.

Adult butterflies drink sweet nectar from flowers. They taste with their feet. Some butterflies sip rotting fruit. They do not only sip nectar.

In fall, many monarchs fly far away. They go to a warmer place for the winter. Monarchs east of the Rocky Mountains spend winter in Mexico. Monarchs west of the Rockies spend winter in California. Some monarchs fly as far as 3,000 miles. They fly to reach their winter home.

The monarchs that fly to Mexico have never been there before. Yet they find the way. They use the sun to stay on course. They have a backup compass. It is for cloudy days.

People can help monarchs. They can plant milkweed in yards and gardens.

Words to know

• hatches: comes out
• milkweed: caterpillar food