This humongous tree is a classic example of an autotroph. An autotroph is the environment’s producer. An autotroph creates its own food and organic compounds from simple substances found in its surroundings such as CO2, O2, and sunlight. Autotrophs do not consume any other organisms in its food making process, unlike heterotrophs. The two types of autotrophs are phototrophs and chemotrophs. The tree in this photo is a phototroph, an organism that uses light as an energy source. A chemotroph uses electron donors as a source of energy.