ÃÛ¶¹ÊÓƵ

From nature:

• Assorted leaves and twigs

From home:

• String
• Clothespins or paper clips
• Paper
• Coloring pencils or felt-tipped pens
• Optional: two chairs
  

• When examining your leaf shadows, have you noticed the many different shapes nature has given to leaves? No one leaf is like the other – each is unique.
  When you see a leaf lying on the ground, do you know which tree it fell from? Can you name the tree? Maybe you have a favorite tree in the garden and recognize its leaves, even when you find them somewhere else? You’ve probably noticed that leaves take different shapes, and sometimes a shape is so distinctive that we remember it.
• But why so many different shapes? That’s not easy to answer. What we do know is that plants adapt to their environment. The leaves of a plant in the desert are generally small and thick, waxy or prickly to better retain moisture. In the rainforest, by contrast, they are often narrow, thin, long, and tapered, so that large volumes of rain can trickle off them easily, and the plant doesn’t drown in water. However, if that’s all there were to it, all the leaves in Switzerland would look the same. But that’s not the case. This is because plants have been around for over 400 million years. And every single species has evolved differently: In the north, plants protect themselves against the cold, but in the south, they protect themselves against the heat. They try to defend themselves against animals (e.g., with their thorns) or to get animals to live on them to help them (e.g., ladybugs). Each plant wants something else from nature and has evolved its shape in whatever way is ideal for it. But all leaves around the world have one thing in common: they transform light into life. This transformation process is called photosynthesis, and it converts light, carbon dioxide and water in the leaves of plants into glucose and oxygen for breathing, making life on Earth possible for all living beings.