Energy in the form of solar energy enters the food chain through photosynthesis performed by the producers.  By feeding on plants and on one-another, animals play an important role in the movement of matter and energy through the food chain. By breaking down dead organic matter, decomposers facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes. The form of energy at the beginning of the food chain is solar energy.