This marine iguana eats algae. The algae give the iguana the energy it needs to live. But where does the algae get their energy? The algae get energy from the sun.
You may also notice that the algae are growing on rocks. How can algae grow without soil? What would happen to the iguana population if the algae could not grow on the rocks?
Marine iguanas live on the Galapagos Islands. These islands used to be covered with hot lava, but are now covered with volcanic rock. The Galapagos Islands are also are home to many different plants and animals. How can an island that used to be covered in lava now be home to new plants and animals?
This chapter discusses how energy flows in an ecosystem and also how new ecosystems form. Think about all these questions as you read this chapter.
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