Trophic levels are the levels organisms occupy in the ecosystem as members of a progressive food chain. The first level organisms are known as primary producers. They get their energy from nutrients in the soil, nutrients in the ocean, or from the sun through the process of photosynthesis. It is here there is the greatest biodiversity, as these organisms can range from microscopic level to the largest of plants. The next level are organisms classified as primary consumers, which are heterotrophs, who consume the primary producers. There is less biodiversity as you move up the food chain. The next level are organisms that feed off the heterotrophs, called secondary consumers. Many of these organisms are carnivores, meat-eaters. The next level of organisms are the tertiary consumers, who feed off both herbivores and carnivores. At this point, we are getting to the top of the food chain, and the biodiversity is much less diversified.