This 2.3-billion year stretch of history is known as the Age of Bacteria. It was during this time that bacteria learned how to recycle matter. Photosynthetic organisms assembled raw energy and available minerals into food stuffs and heterotrophic organisms broke it down to acquire energy and the minerals they needed to live. The short of it is that all the biogeochemical cycles on our planet were formed during the Age of Bacteria. So, to recap.
Energy flows, matter recycles.
These general physical laws are important to understand because they help us to understand how ecosystems are organized. The help us to better appreciate the intricate beauty of life itself. All ecosystems have general principles of organization that maximize the use of energy and make the most efficient use of available minerals. We will study the organization of ecosystems a little bit later on, but it helps to start thinking about it now. Intertidal Zonation Let's take the example of the rocky intertidal ecosystem.