The ultimate source of energy of Earth is the sun. Let me explain, as the sun shines on earth, the plants get energy from it, uses it for the Photosynthesis and then that would give a product of glucose and oxygen. The plants are called producers, then the consumers are the herbivores or omnivores. that includes us, humans, then the energy we and other animals get from the plant is being used ant transferred.On theres also the 2nd order consumers , they are the ones who consume the  the 1st order consumers, they are mostly carnivores or us too. Then the last one, the decomposes, they are the bacteria and fungi thatconsumes  andcorpses or rotten things, then that will repeat aagain

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