The the tulip flowers changed. First the petals were closed up and wrapped around themselves in a bud shape. Then the petals spread open. It was a sunny day. Did you notice the shadows (see arrows) cast on the ground behind the tulips? Shadows are shorter when the sun is high above in the sky. Which of these photos was taken closer to the middle of the day?

All night and early in the morning the tulip flowers are closed up. As the sun warms the earth they gradually open. Did you see what is inside the tulip flower?

By mid day insects are out looking for pollen. Their bodies are warmed up for flight just as the tulip flower opens. They can easily see the colorful yellow and purple parts inside the tulip flower.

Insects visiting the flowers help to pollinate the tulip. Perfect timing!

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